Responses of the ticks Amblyomma hebraeum and A. variegatum to known or potential components of the aggregation-attachment pheromone. III. Aggregation.

Ten known or potential components of the aggregation-attachment pheromone (AAP) of the ticks Amblyomma hebraeum and A. variegatum, as well as mixtures of these components, extracts of prefed males and live prefed males, were tested as aggregation stimulants. In field assays, laboratory-reared unfed male and female ticks were released 20 cm downwind of CO2/pheromone release sites; the numbers of ticks that aggregated at the release sites were recorded after 30 min. In A. variegatum, aggregation was induced by methyl salicylate, o-nitrophenol, 2,6-dichlorophenol, phenylacetaldehyde and some mixtures containing these compounds; a strong aggregation response was induced by an extract of five prefed males A. variegatum and a weak response was induced by an extract of 50 prefed males of A. hebraeum. In A. hebraeum, aggregation was induced by phenylacetaldehyde, mixtures of compounds that included phenylacetaldehyde, extracts of 50 prefed males of A. hebraeum or A. variegatum and 50 live prefed males of A. hebraeum. In A. variegatum, aggregation was inhibited if compounds that do not occur naturally in the AAP of the species were included in mixtures. In A. hebraeum, phenylacetaldehyde appeared to act as an arrestant for ticks that had been attracted to release sites by other compounds.


Responses of the ticks Amblyomma hebraeum and A. variegatum to known or potential components of the aggregation-attachment pheromone. IV. Attachment stimulation of nymphs.

Ten known or potential components of the aggregation-attachment pheromone (AAP) of the ticks Amblyomma hebraeum and A. variegatum, as well as a mixture of these components and extracts of prefed males of the two species, were tested as attachment stimulants for nymphs. Unfed nymphs were confined in linen bags on the ears of rabbits that had been treated with the test compounds, mixture or extracts; the numbers attached were recorded after 24 h. In A. hebraeum, attachment was induced by four compounds (2-methyl propanoic acid, methyl salicylate, o-nitrophenol and salicylaldehyde), the mixture and extracts from both species. In A. variegatum, attachment was induced by three compounds (methyl salicylate, o-nitrophenol and salicylaldehyde), the mixture and extracts from both species. Methyl salicylate and o-nitrophenol are primary components of the AAP of both A. hebraeum and A. variegatum. 2-methyl propanoic acid is a species-specific attachment stimulant for A. hebraeum. Salicylaldehyde, a phenolic compound, is not a naturally occurring AAP component. Nymphs of both species respond to fewer attachment stimulants than the adults and, as shown by their respective host ranges, are less dependent on the AAP in the regulation of attachment than the adults.


The Caenorhabditis elegans cell death gene ced-4 encodes a novel protein and is expressed during the period of extensive programmed cell death.

Mutations in the gene ced-4 block almost all of the programmed cell deaths that normally occur during Caenorhabditis elegans development. We have cloned the ced-4 gene using a ced-4 mutation caused by the insertion of the transposon Tc4. When microinjected into a ced-4 animal, a 4.4 kb DNA fragment derived from the wild-type strain and corresponding to the region of the Tc4 insertion in the mutant ced-4(n1416) rescues the Ced-4 mutant phenotype. The ced-4 gene encodes a 2.2 kb RNA transcript. This mRNA is expressed primarily during embryogenesis, when most programmed cell deaths occur. The Ced-4 protein, as deduced from cDNA and genomic DNA clones, is 549 amino acids in length. Two regions of the putative Ced-4 protein product show some similarity to known calcium-binding domains.


Xenopus maternal RNAs from a dorsal animal blastomere induce a secondary axis in host embryos.

The initial steps of dorsal axis formation are controlled by localized maternal determinants in Drosophila, and a similar process has been proposed in Xenopus. The present study demonstrates that there are axis-inducing RNA molecules located in a specific dorsal midline, animal blastomere (D1.1) of the 16-cell-stage embryo. This blastomere, although in the animal hemisphere at cleavage stages, populates most of the dorsal lip of the blastopore, the region of Spemann's organizer, during gastrulation, and is the major progenitor for dorsal mesodermal tissues. Cytosol from this blastomere causes ventral cells to take a more dorsal fate. RNA from this blastomere induces a secondary axis when injected into ventral blastomeres and restores the dorsal axis in UV-irradiated embryos. In Xenopus, activin beta B, goosecoid and Xwnt-8 RNAs can ectopically induce a dorsal axis; however, none is a maternal transcript. Therefore, the D1.1 blastomere probably contains dorsal determinant(s) that are either maternal members of these gene families, or other presently unknown molecule(s). Regardless of the identity of the determinant(s), this study presents the first indication that Xenopus maternal RNAs in the dorsal animal hemisphere are able to organize the dorsal axis.


Primary culture of single ectodermal precursors of Drosophila reveals a dorsoventral prepattern of intrinsic neurogenic and epidermogenic capabilities at the early gastrula stage.

We have analyzed the development in vitro of individual precursor cells from the presumptive truncal segmental ectoderm of the Drosophila embryo to study the intrinsic component in the determination of cell fate. For each cultured cell, the original position within as well as the developmental stage of the donor embryo were known. Cells removed from the ventral neurogenic region develop neural clones. Cells from the dorsal ectoderm and from the dorsalmost part of the ventral neurogenic ectoderm develop epidermal clones. These two classes of clones differ with respect to their division pattern, adhesiveness, cell morphologies and the expression of cell-specific markers. Mixed neural/epidermal clones were obtained from a fraction of precursors at almost all dorsoventral sites. We conclude that, at the onset of gastrulation, precursor cells of the truncal segmental ectoderm already have the capability to develop as either neuroblasts or epidermoblasts in the absence of further cell interactions. At the same time, positional cues distributed along the dorsoventral axis equip precursors with intrinsic preferences towards the neural or epidermal fate, thus defining a prepattern of high neurogenic preferences ventrally, and high epidermogenic preferences dorsally. It is likely that this prepattern is involved in defining the extent of the ventral neurogenic and dorsal epidermogenic regions of the ectoderm. The roles of intrinsic capabilities versus extrinsic influences in the regulation of the characteristic pattern of segregation of the two lineages are discussed.


The presence of hepatocyte growth factor in the developing rat.

Hepatocyte growth factor (HGF), a heparin-binding polypeptide mitogen, stimulates DNA synthesis in adult rat and human hepatocytes and in several other cells of epithelial origin. Recently, it was determined that scatter factor (SF), a protein that has been shown to cause the dispersion and migration of epithelial cells in culture, is identical to HGF. Moreover, the receptor for HGF was identified as the product of the proto-oncogene, c-MET, a tyrosine kinase-containing transmembrane protein. c-MET expression has been reported in a variety of adult and embryonic mouse tissues. Similarly, we and others have demonstrated that HGF is expressed in various adult rat and human tissues. In the present study, the tissue distribution of HGF during rat development was determined by immunohistochemistry using an HGF-specific polyclonal antiserum. Between day 12 and day 19, immunoreactivity for HGF was present in various locations such as hematopoietic cells, somites, squamous epithelium of the esophagus and skin, periventricular germinal matrix of the brain, bronchial epithelium, renal collecting tubules and chondrocytes. After day 19, HGF immunoreactivity was also present in the pancreas, submaxillary glands and neural tissues. In addition to immunolocalizing HGF in tissue sections, bioreactive and immunoreactive HGF was extracted and purified from rat fetuses. Other studies demonstrated the presence of HGF and c-MET mRNA in total fetal rat, and in fetal and neonatal rat liver. Addition of purified HGF to fetal and neonatal rat liver cultures enriched for hepatocytes stimulated DNA synthesis up to six-fold over controls. These findings strongly suggest a pivotal role for this potent regulator of growth and development.


The Drosophila cdc25 homolog twine is required for meiosis.

We have identified a second cdc25 homolog in Drosophila. In contrast to string (the first homolog identified in Drosophila) this second homolog, twine, does not function in the mitotic cell cycle, but is specialized for meiosis. Expression of twine was observed exclusively in male and female gonads. twine transcripts are present in germ cells during meiosis, and appear only late during gametogenesis, well after the end of the mitotic germ cell divisions. The sterile Drosophila mutant, mat(2)synHB5, which had previously been isolated and mapped to the same genomic region as twine (35F), was found to carry a missense mutation in the twine gene. This missense mutation in twine abolished its ability to complement a mutation in Schizosaccharomyces pombe cdc25. Phenotypic analysis of mat(2)synHB5 mutant flies revealed a complete block of meiosis in males and severe meiotic defects in females.


Biological and molecular correlates between induced dedifferentiation and spore germination in Dictyostelium.

When developing cultures of Dictyostelium discoideum are disaggregated at any time prior to cell wall formation and challenged to reinitiate development, amoebae will progress through the original sequence of morphogenetic stages, but the second time through they will do so in roughly one-tenth the original time, a process known as 'rapid recapitulation'. However, if disaggregated cells are suspended in nutrient medium, they enter a program of dedifferentiation during which they lose the capacity to rapidly recapitulate after an 80 minute lag period in a process known as 'erasure'. Here we show that cells that have completed the morphogenetic program and emerge from spore coats in the process of germination have also erased. In addition, the germination-specific 270 gene family is expressed during induced dedifferentiation in a unique fashion, and a germination-defective mutant exhibits a dramatic delay in erasure without concomitant defects in the program of gene regulation accompanying induced dedifferentiation. These results suggest for the first time that induced dedifferentiation and spore germination share some common processes in converting cells from a developmental to vegetative state.


Induction of vasculogenesis and hematopoiesis in vitro.

Despite a large number of investigations of embryonic vascular development, in particular in avian embryos, the conditions under which the endothelial and hematopoietic cell lineages emerge remain unknown. As we demonstrate here, both endothelial and hematopoietic cells can be induced by treatment of dissociated quail epiblast with fibroblast growth factors in vitro. These cells aggregate in characteristic blood islands. In long-term culture, the induced endothelial cells gave rise to vascular structures in vitro, i.e. vasculogenesis. No induction was observed in the absence of fibroblast growth factors, and other growth factors like TGF-beta, TGF-alpha and EGF were not capable of inducing blood island formation. Thus, the dissociated quail epiblast provides a remarkably simple test system to investigate cell lineage diversification in higher vertebrates.


Determination of epithelial half-somites in skeletal morphogenesis.

The segmental body plan of vertebrates arises from the metameric organization of the paraxial mesoderm into somites. Each mesodermal somite is subdivided into at least two distinct domains: rostral and caudal. The segmental pattern of dorsal root ganglia, sympathetic ganglia and nerves is imposed by differential properties of either somitic domain. In the present work, we have extended these studies by investigating the contribution of rostral or caudal-half somites to vertebral development using grafts of multiple somite halves. In both rostral and caudal somitic implants, the grafted mesoderm dissociates normally into sclerotome and dermomyotome, and the sclerotome further develops into vertebrae. However, the morphogenetic capabilities of each somitic half differ. The pedicle of the vertebral arch is almost continuous in caudal half-somite grafts and is virtually absent in rostral half-somite implants. Similarly, the intervertebral disk is present in rostral half-somite chimeras, and much reduced or virtually absent in caudal somite chimeras. Thus, only the caudal half cells are committed to give rise to the vertebral pedicle, and only the rostral half cells are committed to give rise to the fibrocartilage of the intervertebral disk. Each vertebra is therefore composed of a pedicle-containing area, apparently formed by the caudal half-somite, followed by a pedicle-free zone, the intervertebral foramen, derived from the rostral somite. These data directly support the hypothesis of resegmentation, in which vertebrae arise by fusion of the caudal and rostral halves of two consecutive somites.


Molecular gradients along the proximal-distal axis of embryonic insect legs: possible guidance cues of pioneer axon growth.

It has been proposed that gradients of environmental cues direct the proximal growth of pioneer axons in embryonic insect legs. Hybridoma techniques have been used to produce 3 monoclonal antibodies (mAbs) that bind to components associated with the basal lamina/extracellular matrix that are non-uniformly distributed along the proximal-distal axis of cockroach legs at the time of pioneer axon growth. Two of these mAbs, PROD-1 and PROD-2, label the proximal parts of the leg more intensely than the distal ends. The other mAb, DIP-1, has the reverse pattern of binding with the distal parts of the leg labeled more intensely. The graded distribution of these antigens only occurs just prior to and during the growth period of the Ti1 pioneer axons. Western blot analyses and immunoprecipitations have identified the protein antigens recognized by these mAbs. The spatial and temporal distributions of these molecules in the legs and the CNS make them good candidates for environmental guidance cues of pioneer axon growth.


Ontogeny of calbindin-D28K and calbindin-D9K in the mouse kidney, duodenum, cerebellum and placenta.

The appearance of the calcium-binding proteins (CaBP-D28K and CaBP-D9K) in embryonic mice tissues was determined using a sensitive immunohistochemical assay. CaBP-D28K first appears in myenteric nerve plexuses of the duodenum on day E15, in duodenal villus cells on day E16, in Purkinje cells of the cerebellum on day E19, in cells of the mesonephric duct on day E11 and in the metanephric duct on day E12. CaBP-D9K first appears in enterocytes of the duodenum on day E18, in trophoblastic giant cells (TGC) of the placenta on day E10, and in the metanephric duct on day E15. A differential time of appearance and colocalization of the two CaBPs is demonstrated in the embryonic mouse kidney, suggesting either that vitamin D does not control both CaBPs in the foetus or that the vitamin D control is unequal. The early appearance and location of CaBP-D9K in TGCs may suggest that these cells play an important role in transplacental transfer of calcium.


Cytoarchitectural development of the human dentate nucleus: a Golgi study.

Golgi-stained sections of the human cerebellar dentate nucleus (DN) at various gestational ages were examined to study the dendritic proliferation and maturation of the DN neurons. Bipolar cells were seen at 14-15 weeks. By 19-20 weeks, three cell types were identifiable: bipolar, hemispheric and pyriform. The cells of the dorsomedial region matured earlier than those of the ventrolateral region. In addition to the above cell types, multipolar and nuclear boundary cells were observable at 24-25 weeks. The five cell types persisted during subsequent development. At no stage of development was any neuronal organizational pattern apparent. A remarkable dendritic proliferation occurred at 27-28 weeks. Spines and filiform processes were seen at 34 weeks of intrauterine life.


First appearance of orthogonal arrays of particles in Müller cell membranes depends on retina maturation.

A freeze-fracture analysis was undertaken to investigate both the appearance of orthogonal arrays of particles (OAP) in the Müller cell endfoot membrane at the retina-vitreous border and the endfoot size during development of two avian species. Chickens and pigeons have a common length of development until hatching (21 days), but differ in maturation velocity. In the chicken, the first OAP appear in the central retina at embryonic day 18 (E18), in the peripheral retina at E19. The OAP density increases rapidly. In the pigeon, the first OAP appear 6 days after hatching when the eyes are opened. In both species, the size of endfeet is maximal when the OAP first appear and is reduced thereafter. In the chicken, during the time up to adulthood both the mean endfoot size and the retina area increase 6-fold suggesting that the number of endfeet remains constant during growth of their individual area. In the pigeon, after an initial increase of mean endfoot area this decreases until adulthood, despite continuous growth of the eye. This strongly suggests that during retina growth the number of Müller cell endfeet increases. It is concluded that these alterations of Müller cell membranes reflect some functional aspects of retina maturation.


Naturally occurring degrading events in axon terminals of the dentate gyrus and stratum lucidum in the spiny mouse (Acomys cahirinus) during maturation, adulthood and aging.

The naturally occurring dynamics of presynaptic axon terminals were investigated in the dentate gyrus and stratum lucidum of the spiny mouse (Acomys cahirinus) during maturation, adulthood and aging. A sensitive and selective silver-staining technique was applied to analyze neuronal lysosome accumulation (LA), indicating synaptic degradation during development. LA was quantified by counting silver grains in the inner third and outer two thirds of the molecular layer, granular layer, and the infragranular layer of the dentate gyrus, and in the strata oriens, pyramidale, lucidum and radiatum of the medial and distal regio inferior on postnatal days 21, 28, 95, 730, and 1,460. In young and adult animals, LA was most abundant within the inner molecular layer. When animals grew older, LA densities obviously decreased in the inner molecular layer but increased in the outer molecular layer. Within the stratum lucidum only the distal regio inferior showed an extremely high LA density on postnatal day 21, dramatically decreasing thereafter and reaching adult low values during the first postnatal month. By electron microscopy in the inner molecular layer we found LA in large synaptic boutons and small terminals both with distinct synaptic contact zones. Degrading presynaptic profiles may further accumulate dense bodies, zones with completely disorganized cytoplasm, and lamellarly organized whorled membrane debris. In the distal regio inferior comparable phenomena were observed in typical mossy fiber boutons. Despite these degrading events, no electron-dense degenerating terminals were found. These results on naturally occurring nondegenerative synaptic degradation are discussed with current concepts of synaptic turnover and remodelling in the developing, adult and aging brain.


Glycoprotein processing is required for completion but not initiation of oligodendroglial differentiation from its bipotential progenitor cell.

The role of N-linked glycoproteins in the development of oligodendroglia has been studied in a culture system that initially contains the progenitor cell for oligodendroglia and type 2 astrocytes. The progenitor cells, derived from mixed glial primary cultures of newborn rat cerebrum, were studied under culture conditions that we have shown previously to induce oligodendroglial differentiation. Castanospermine was used to inhibit processing of N-linked glycoproteins by its inhibitory action on glucosidase I, the enzyme responsible for the initial trimming of glucose residues from the glucosylated high mannose core oligosaccharide derived from the dolichol pathway. Exposure to castanospermine had no effect on the initial commitment of the progenitors to oligodendroglial differentiation, i.e. 95% of both control and castanospermine-treated cells became galactocerebroside (GC) positive. However, the developmental inductions of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) and glycerol-3-phosphate dehydrogenase (GPDH) and the elaboration of a network of fine interconnecting processes were prevented by the castanospermine exposure. No effect of castanospermine on cell number was observed. A major effect of the inhibitor on glycoprotein processing was manifested by an accumulation of high mannose glycoproteins, of abnormal oligosaccharide structure, compatible with the inhibition of glucosidase I.(ABSTRACT TRUNCATED AT 250 WORDS)


Establishment of a culture system for the study of oligodendroglial development: complementary effects of boiled serum and astrocyte extract.

Mixed glial primary cultures derived from neonatal rat brain were used to isolate the progenitor glial cell with the capacity to differentiate into oligodendroglia or type 2 astrocytes depending on the culture medium. Subcultures composed primarily of this progenitor were utilized, first, to study the regulation of oligodendroglial differentiation by two factors added to chemically defined medium (CDM), i.e. boiled fetal calf serum (FCS) and cellular extract of type 1 astrocytes, and, second, to devise culture conditions that would cause the progenitor cells to differentiate virtually exclusively along oligodendroglial lines (judged by immunologically identified expression of galactocerebroside; GC) and with high specific and total activity of the oligodendroglial enzymes, 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) and glycerol-3-phosphate dehydrogenase (GPDH). Addition of untreated FCS to CDM of the progenitors resulted in 6 days in richly cellular, mixed glial cultures composed of slightly more GFAP-positive astrocytes than oligodendroglia. Addition of boiled FCS to CDM of the progenitors resulted in 6 days in cultures composed almost exclusively (95%) of GC-positive cells and with high specific activity of CNP. This effect of boiled serum, compared to untreated serum, was related to virtual elimination of astrocytes, in the presence of continued differentiation to GC-positive oligodendroglia. Addition of type 1 astrocyte extract as well as boiled FCS to CDM was necessary to generate high specific activity of GPDH. Additionally, the total number of oligodendroglia increased 2-fold when astrocyte extract as well as boiled FCS was added to the CDM.(ABSTRACT TRUNCATED AT 250 WORDS)


Lack of cell density-dependent changes in gangliosides of rat primary culture neurons.

Cell density-dependent changes in neuronal gangliosides, primarily relating to neurite outgrowth under dense to sparse conditions, were examined at cell seeding densities over an 8-fold range. During the first 24 h of incubation, the dissociated fetal rat neurons showed characteristic protrusion of neurites as a function of cell density. Ganglioside and protein contents per the same cell numbers were higher in dense cultures than sparse ones. However, the ganglioside pattern was essentially unchanged from dense to sparse culture, showing a predominance of GD3 and GT1b. The biosynthetic activity of gangliosides, as estimated by the incorporation of 3H-labeled N-acetyl-D-mannosamine, a precursor of sialic acid, was similar at various cell densities, with the labeling of b-series gangliosides predominating. The expression of neuronal gangliosides was monitored by indirect immunofluorescence using anti-GM1 antibody, but was found to be poor. A2B5 antigen, which was mainly identified as GT1b, appeared to be readily expressed on cell surfaces in sparse cultures. In contrast, the highly polysialylated form of the neural cell adhesion molecule (NCAM-H) was fully expressed on both the neurites and cell soma at various cell densities. The results suggest that the polysialic acids in NCAM have more important roles in neurite outgrowth than gangliosides, since the composition and synthesis of gangliosides are not affected by cell seeding density.


The risk of medical complications after female circumcision.

The medical complications of the practice of circumcision were studied in 290 Somali women between ages of 18-54. Thirty-nine percent of the interviewed women had experienced significant complications after circumcision, most commonly haemorrhage, infection or urinary retention. Thirty-seven of the women reported a late complication of circumcision. Among these complications were dermoid cyst at the site of the amputated clitoris, urinary problems such as pain at micturition, dribbling urine incontinence and poor urinary flow. Forty of the women had experienced problems at the time of menarche and ten of them were operated because of haematocolpos. Most of the married women of the study sample were defibulated naturally by their husbands.


Audit of hysterectomies at the Aga Khan Hospital, Nairobi: justification of operative indications.

An audit of 381 hysterectomies performed over a 5 year period (1986-1990) was carried out. In order to assess justification of the indication for hysterectomy pre-operative diagnoses were divided into two groups: those potentially confirmable by pathologic study and those not potentially confirmable by pathologic study. Out of the 273 cases studied in the first group, 246 (90.1%) were justified, while out of the 108 cases studied in the second group, 82 (75.9%) were justified. An overall 86% justification rate was observed. Adenomyosis as a histopathologic finding was seen more commonly in Asian than African patients (P < 0.005). Morbidity rate was 20% and there were no mortalities. The procedure in general was considered safe and justified.


Tumours of the eye and orbit in Ibadan.

Four hundred and forty ocular and orbital tumours seen in Ibadan over 11-year-period (1980-1990) are reviewed. Three quarters of the 252 patients who had enucleation had malignant neoplasms, of which 55% were retinoblastomas. The mean age of patients with retinoblastomas (3.2 years) was less than that of patients with carcinoma and malignant melanomas (47 years). Malignant melanomas were rare neoplasms in Ibadan. The commonest orbital lymphoma was Burkitt's lymphoma. Only 24% of the enucleated eyes had inflammatory conditions, of which 38% gave a positive history of trauma. Inflammatory lesions were the commonest benign ocular diseases accounting for 33% of these latter cases. Postmeasles keratitis was a significant associated finding in these patients.


Post-operative management of pterygium in Jos, Nigeria--comparison of antibiotics, steroids and opticrom.

Eighty six patients with a total of 125 pterygium-affected eyes were treated by surgical excision and one of three post-operative topical, medical adjuvants--antibiotics, steroids or Opticrom--to try and control the recurrence rate. The result showed that opticrom 2% ophthalmic drops was most effective in controlling pterygium recurrence. Steroids proved more effective than antibiotics.


Observations on the epidemiology of plague in Tanzania during the period 1974-1988.

Field and commensal rodents and shrews were live-trapped from selected areas in each of the six zones of the Republic, namely North-eastern, Eastern, Central-western, South-western, Southern and Seaports. The captured animals, small ruminants, humans and small carnivores were serologically tested for specific plague antibodies, using the Passive haemagglutination (PHA) and Passive haemagglutination Inhibition (PHAI) techniques. Taxonomic studies and population densities of rodents and their ectoparasasites were carried out. A total of 5638 animals were captured and 79.9% of them were tested for plague. Of those tested, 2.4% contained agglutinating plague antibodies at serum dilutions of 1:20 and above. The positive rodents were found in Lushoto, Mbulu, Chunya and Monduli districts, as well as at Tanga seaport. These include R. rattus, M. natalensis, A. niloticus and Otomys spp. A total of 7480 human, 293 carnivorous and 425 small ruminant sera were also tested for plague. Seven (2.4%) of the carnivores were positive at serum titres of 1:20-1:80. All the small ruminants were negative. Likewise, 1.4% of the tested human sera contained specific plague antibodies at titres ranging from 1:20-1:60. Out of 6480 fleas collected from the captured small mammals, 5476 were identified. Of these, 34.5%, 20.4%, and 17.8% were X. brasiliensis, D. lypusus and X. cheopis respectively. It was generally concluded that plague was still endemic in several parts of the country, that some foci were active, and that there was a potential risk of accidental introduction and/or transfer of the disease into or out of the country. Establishment and maintenance of surveillance services and facilitating research and control programmes of the disease were recommended.


Sources of intra-operative bacterial colonization of clean surgical wounds and subsequent post-operative wound infection in a Nigerian hospital.

The incidence of postsurgical clean wound infection in 101 consecutive operations was 1.98%. Staphylococci were the predominant bacteria cultured from the anterior nares of the patients and attending surgical personnel--and were found to colonize the wounds. The nasal carriage rates of Staphylococcus aureus amongst the patients and surgical staff were 12.1% and 17.% respectively. Group III and non-typeable (NT) S. aureus strains accounted for about 65% of S. aureus isolates cultured from the anterior nares. A low incidence of nasal carriage of S. aureus isolates correlated with low incidence of wound sepsis. The operating room air seemed considerably contaminated but this did not reflect in high incidence of postsurgical wound sepsis. Our results suggest patients microflora and operating room air were the major sources of intra-operative bacterial colonization of wound at this centre.


The role of the laboratory in a Chlamydia control programme in a developing country.

The laboratory components of a Chlamydia trachomatis disease control programme for a developing country are reviewed. Early diagnosis of chlamydial infections is the most cost effective means of preventing the long term sequelae of trachoma, pelvic inflammatory disease, ectopic pregnancy and infertility, which are now a major public health burden to the health care system in developing countries. Public health strategies are required to establish both a co-ordinated limited system of laboratory services, and to promote the diagnosis and treatment of disease syndromes in the absence of laboratory support. Laboratory tests for the specific diagnoses of chlamydial infections requiring different levels of expertise and equipment can be instituted within settings appropriate to the resources and technical expertise available. Emphasis is given to appropriate cost effective utilization of laboratory testing.


A prospective study of 110 Ethiopians with thyrotoxicosis.

One hundred and ten Ethiopian thyrotoxic patients were studied between February 1986 and January 1991 in a weekly endocrine clinic of Tikur Anbessa Teaching Hospital (TATH) in Addis Ababa, Ethiopia. This gives an incidence of 22 patients per year. There were 14 males and 96 females (M:F = 1:7). Fifty three patients (48.2%) had Graves' hyperthyroidism, 37 (33.7%) toxic multinodular goitre (TMNG), 14 (12.7%) toxic adenoma, 4 (3.6%) Jodbasedow phenomenon and 2 (1.8%) had thyroiditis. The mean age was 29.2 +/- 9.8 (+/- S.D.) years for Graves' cases, 49.0 +/- 10.9 years for TMNG cases and 46.4 +/- 15.9 years for toxic adenoma cases. The clinical presentation was similar to other reported series. The majority (88.7%) of Graves' patients were below 40 years while 75.7% of TMNG patients were over 40 years of age; this is in keeping with the observed younger age incidence of Graves' hyperthyroidism and older age incidence of TMNG. All patients responded to propylthiouracil therapy and no major side effect was recognized. Nine patients underwent sub-total thyroidectomy of whom one became hypothyroid a year later. One became toxic after a year, while 6 remained euthyroid 3 years after the surgery; the other patient did not return subsequently. The result of this study shows that thyrotoxicosis is not a rare condition in Ethiopia.


The first ten years of heart surgery in Kenya--aspirations, dilemmas and possibilities.

This paper looks at the beginnings of cardiac surgery in Kenya with relevant clinical data as well as the overall historical background to various cardiovascular operations which preceded formal establishment of the Thoracic and Cardiovascular Surgical Unit at the Kenyatta National Hospital. Similar activities in other hospitals in Nairobi and elsewhere in Kenya have been excluded. The Unit separated from general surgical wards in January 1973. By the end of 1983, a total of 208 open heart operations had been done by various teams in the Unit. A number of other heart operations were also undertaken. Those done before that decade are also highlighted back to 1950. The many problems that the Unit faced and still faces are also identified in this paper and the dream of making it a Centre of Excellence revisited.


Salivary gland tumours in Kenya.

Four hundred and seventeen tumours of salivary glands in Kenya were analysed. There is no evidence of higher incidence of salivary tumours than in non-African countries. The pattern of distribution differed from that of western countries, but in conformity with most African series showed a low proportion of tumours of the parotid gland and high proportion of tumours in the submandibular gland and the palate. The involvement of the palate by salivary gland tumour is very prominent in the African series and particularly more so in the females. Malignant tumours of the palate and parotid glands were frequent but were lower than those reported in other African series. On the other hand malignant salivary gland tumours of the submandibular glands while lower than those of the western countries, were higher than those of other African series.


Inflammatory pseudotumour of the liver: a case report.

A case of inflammatory pseudotumour of the liver is reported. Together with a brief review of inflammatory pseudotumours we also present the clinical picture and pathologic findings of this very rare tumour-like condition with only 31 cases quoted in the medical literature. We also discuss the difficulty of making a correct diagnosis of the condition.


Murder during sleep-walking.

The issue of criminal responsibility is no easy matter to resolve at times. One such instance is offered by the case of the sleep walker who commits a violent act in the course of his sleep. However, sleep-walking disorder has not received much professional attention. In this article the author reports one case of sleep-waking disorder (Somnambulism) in which murder was committed in cold blood.


The effect of nocotiana tabacum (snuff) on blood pressure and pulse rate of Nigerians.

Nutritional and environmental factors are now known to affect the blood pressure and pulse rate of man. The present study investigated the effect of nicotiana tabacum on these parameters. Thirty-three male Nigerians (20-68 years) living in Calabar, Nigeria were used for this study. The subjects were treated at three different periods with snuff containing varied concentrations of Natron (0.5g and 10g/100g of snuff) and their systolic and diastolic pressures as well as pulse rate were measured at intervals of 30 minutes up to a maximum of 90 minutes. Each subject served as his own control. There were significant and time-dependent increases in the parameters measured. In addition, the increases were more marked in the absence of Natron than in its presence.


Phantom pregnancy at Muhimbili.

This is a case report on phantom pregnancy at Muhimbili. Relevant factors pertaining to personality of the patient, the experienced psycho-social stresses, the medical history and possible causes of symptom formation culminating in pseudocyesis are looked into and discussed.


Rat bite fever: a case report of a Kenyan.

Rat bite fever has not been reported from Kenya previously. A case of 17 year old Kenyan male who was diagnosed to have rat bite fever after a bite of domestic rat is described. The history, clinical features and demonstration of spirillum like organisms from a thick blood film suggest infection due to spirillum minus. The patient recovered completely after a course of penicillin and gentamicin.


Iron deficiency in infancy; easy to prevent--or is it?

Despite major advances in our knowledge of iron nutrition in infancy, iron deficiency remains a significant problem in the UK. The precise size of the problem is unknown, but there appears to be a higher risk amongst certain ethnic groups. Nutritional iron deficiency appears after the age of 6 months and is undoubtedly linked to inappropriate feeding practice. High bioavailability of iron in weaning foods is of paramount importance in preventing iron deficiency, whether using family foods or commercially available products, and further information about different foods and diets is needed. The long-term detrimental effect on mental development makes prevention of iron deficiency a high priority public health objective for the 1990s.


Mastectomy versus breast conservation surgery: mental health effects at long-term follow-up.

Between 1984 and 1989, 129 Stage 1 and Stage 2 breast cancer patients were entered into a behavioral study in Pittsburgh. Approximately 70% of these patients had elected to have breast conservation (lumpectomy) surgery, with the remainder choosing mastectomy. Using the Profile of Mood States, a measure of perceived social support, and Karnofsky ratings of physical functional status, patients were assessed 3 to 5 days following surgery and again 3 and 15 months following surgery. The data were analyzed using a repeated-measures analysis of covariance, adjusting for aggressiveness of chemotherapy. Compared to mastectomy patients, patients who received breast conservation surgery were rated as more functional by observers, but they perceived themselves as having less energy and less emotional support, especially over the first 3 months of the recovery period. Because there is accumulating evidence that emotional support may act as a stress buffer in various populations and may have survival value, these findings may be particularly troublesome. This study shows that breast conservation surgery is not a psychosocial panacea. Patients whose breasts are spared, especially younger patients, have psychological symptoms that appear acutely worse in the short run and, in the end, are similar to those of patients who elect to have mastectomies. Therefore, patients choosing lumpectomies are not necessarily psychosocially better off than those electing to have mastectomies. Additionally, these patients, particularly younger patients, may require greater social support and potential mental health interventions than they seem to be receiving.


Acute exercise: buffering psychosocial stress responses in women.

We evaluated the experimental hypothesis that an acute bout of aerobic exercise (AE) serves as a buffer to psychosocial stress responses in low to moderate physically fit women. Forty-eight (24 White, 24 Black) 25- to 40-year-old women participated in two counterbalanced experimental conditions: an attention control and a 40-min bout of AE at 70% heart rate (HR) reserve. The attention control and AE treatments were followed by (a) 30 min of quiet rest, (b) exposure to mental and interpersonal threat, and (c) 5 min of recovery. Blood pressure (BP) and HR were monitored at baseline, during the stressors, and throughout recovery. Self-reported distress was assessed before each stressor and upon completion of the recovery period. The results provided clear evidence that exercise dampens BP reactivity to psychosocial stress. Additionally, compared with the attention placebo control, AE reduced both the frequency and intensity of anxiety-related thoughts that occur in anticipation of interpersonal threat and challenge.


Health beliefs and promotion of HIV-preventive intentions among teenagers: a Scottish perspective.

Beliefs concerning the spread of the human immunodeficiency virus (HIV) and preventive behaviors were examined in a sample of 351 sexually active Scottish teenagers. A postal questionnaire, including measures of variables specified by the health belief model (HBM) and preventive intentions, was employed. The relation between HBM measures and reported endorsement of HIV-preventive intentions was investigated. Results indicated that, in general, respondents intended to use condoms with new sexual partners. The majority also intended to carry condoms if they thought they might have sex with a new partner and to ask potential partners about their previous sexual history. Multiple-regression analyses showed that measures of health beliefs, gender, age, sexual experience, and previous condom use accounted for 17.8% to 24.3% of the variance in reported preventive intentions. Perceived barriers to preventive behaviors were found to be important predictors. However, the overall pattern of results raised questions concerning the adequacy of the HBM as a model of the determinants of HIV-preventive intentions, and the need for an extended model is discussed. Separate analyses were conducted for men and women and for 16- and 18-year-olds, and the implications for modeling intention formation in these subgroups are considered. The relevance of these findings to HIV-preventive campaigns is also discussed.


Changing knowledge and attitudes about skin cancer risk factors in adolescents.

We examined knowledge, attitudes, and behaviors related to skin cancer, sun exposure, sunscreen use, and use of tanning booths in 903 female and 800 male adolescents. The effectiveness of a brief, school-based intervention designed to increase teens' knowledge and preventive attitudes about skin cancer was also evaluated. Females, older students, and those with high-risk skin types were most likely to use sunscreen and to take precautions. However, overall level of protection was low. Intentions to take precautions were associated with levels of perceived susceptibility to skin cancer, attitudes about the benefits of sun exposure, skin type, and sex. Beyond intentions, sunscreen use was associated with perceived susceptibility and skin type. The one-session, school-based intervention significantly increased knowledge and perceived susceptibility to skin cancer but not behavioral intentions.


On becoming involved with drugs: modeling adolescent drug use over time.

We tested a model of the process of becoming involved with drugs during junior high. The sample included 698 students who were not using alcohol, cigarettes, or marijuana during Grade 7 (T1); the follow-up data points were 12 and 15 months later (T2 and T3). The final model, which predicted 72% of the variance in drug use at T3, provides support for hypotheses drawn from both social and cognitive theories. Weak familial and school attachments fostered use by increasing the likelihood of exposure to pro-drug social influences (drug use offers); weak bonds with school also directly affected cognitive motivations (lower resistance self-efficacy [RSE] and more positive outcome expectancies). In turn, social influences at T1 played a dominant role in initial use at T2, but cognitive motivations were also significant. At T3, prior use assumed the most prominent position. Drug-specific measures of RSE and expected use directly affected later use of that substance. The results indicate that both generic and drug-specific effects are needed to explain adolescent drug use. Implications for prevention programs are discussed.


The stages and processes of exercise adoption and maintenance in a worksite sample.

We applied the model of the stages and processes of change to exercise adoption and maintenance. This model has shown promise in advancing theory and treatment of the addictions and other negative health behaviors, but there have been few systematic attempts to apply the model to positive health behaviors, such as exercise adoption. Questionnaires dealing with the stages and processes of exercise change were developed and administered to a sample of 1,172 participants in a worksite health promotion project. The sample was split randomly into halves for (a) initial model development and testing and (b) confirmatory measurement model testing. Additional model confirmation was obtained by examining the hierarchical structure of the processes of change and by conducting Stage x Process analyses. Results suggest that the underlying constructs derived from smoking cessation and other addictive behaviors can be generalized to exercise behavior. Understanding the stages and processes of exercise behavior change may yield important information for enhancing exercise adoption, adherence, and relapse prevention at both individual and public health levels.


An educational test of health behavior models in relation to emergency helping.

This study used a true experimental design to evaluate the quality and occurrence of emergency helping behavior among university first-aid students in response to a supplemental educational unit designed to improve bystander helping. The educational unit addressed the inhibitors of emergency helping behavior within the framework of bystander behavior models and was delivered using several behavior modification strategies. Using chi-square analysis, it was found that the 43 treatment students exposed to the supplemental unit responded appropriately to a simulated emergency more often than 41 similar control students not exposed to the unit (32.6% vs. 7.3%, p = .004) and that the effect was confined primarily to women (p = .001). Future emergency care education incorporating similar theory-based educational strategies might improve trained bystander responsiveness and thus enhance the efficiency of prehospital care. Theoretical and future research implications are discussed.


Patterns of social desirability and anger in young men with a parental history of hypertension: association with cardiovascular activity.

We identified, via cluster analysis, subgroups of young men with a parental history of hypertension (PH+) who differed in their profiles of need for approval, covert experience of anger, and extent to which they express anger when provoked. The PH+ subgroup with high need for approval and low anger acknowledgment scored higher on denial but lower on measures of angry temperament and overt display of anger than did the PH+ subgroup with low need for approval and high anger acknowledgment or men without a parental history of hypertension (PH-). Moreover, the PH+ subgroup with high need for approval and low anger acknowledgment manifested significantly higher stressor-induced blood pressure (BP) responsivity than did the other two groups. Possible relations between parental history status, need for approval, anger, BP reactivity, and essential hypertension are discussed.


Stages of readiness to quit smoking: population prevalence and correlates.

We examined the population prevalence and correlates of stages in smokers' readiness to quit, using data from 1,048 smokers recruited in a self-weighting, multistage, systematic clustered area sample from 0.44% of South Australian dwellings, with an 89% response rate. Smokers in the precontemplation stage comprised 24.1% of the sample, smokers in the contemplation stage comprised 47.2%, and smokers in the preparation stage comprised 28.7%. No sociodemographic variables (i.e., age, sex, marital status, educational level) were found to be significant independent predictors of membership in the different stages. The five significant independent predictors of being in the precontemplation stage (vs. the contemplation stage) were (a) having a higher confidence of quitting, (b) seeing fewer health risks associated with smoking, (c) not having made an attempt to quit, (d) seeing quitting as more difficult, and (e) smoking 25 or more cigarettes a day. The two significant independent predictors of being in the contemplation stage (vs. the preparation stage) were (a) having lower confidence of quitting and (b) not having tried to quit. We discuss implications for the understanding of smoking behavior in populations and also consider how cessation campaigns might address the factors associated with different stages of readiness to quit.


Relation of level of exercise, age, and weight-cycling history to weight and eating concerns in male and female runners.

We examined the association between level of exercise and degree of weight preoccupation in a large sample of male and female runners, as well as risk factors posited to influence weight and eating concerns in the general population. Subjects were 2,459 males and 1,786 females who had completed a questionnaire on weight and eating concerns in a national running magazine. Eight percent of the males and 24% of the females had symptomatic scores on the Eating Attitudes Test (EAT). Exercise level, defined as weekly running mileage, was positively associated with excessive weight and eating concerns in males but not in females. Both sexes with a history of weight cycling were more likely to have symptomatic EAT scores than those with no such history. These results highlight the importance of studying these concerns in males as well as females and of examining the role of exercise level and weight-cycling history in the development of serious weight preoccupations.


Human cerebrospinal fluid protein database: edition 1992.

Two-dimensional electrophoresis maps of human cerebrospinal fluid proteins are presented in the form of labeled images. 931 protein spots are identified in spinal fluid from a normal volunteer. Distinct spots that represent variants of the same protein, especially posttranslational modifications, are estimated to reduce the 931 different spots to < 200 different proteins. 248 spots of 29 protein groups have been identified and are indicated on enlargements of specific gel regions. The distribution of protein abundance, mass, charge and shape characteristics of these normal 931 spinal fluid spots are graphically profiled. Analysis of the shape parameter "vertical height: width ratio" reveals that a ratio > 3.5 correlates with glycoproteins, enabling their identification simply by image analysis. Proteins that are not present on the normal map, but appear in spinal fluid in patients with schizophrenia and Creutzfeldt-Jakob disease are illustrated on additional maps.


The gene-protein database of Escherichia coli: edition 5.

The gene-protein database of Escherichia coli is both an index relating a gene to its protein product on two-dimensional gels, and a catalog of information about the function, regulation, and genetics of individual proteins obtained from two-dimensional gel analysis or collated from the literature. Edition 5 has 102 new entries--a 15% increase in the number of annotated two-dimensional gel spots. The large increase in this edition was accomplished in part by the use of a new method for expression analysis of ordered segments of the E. coli genome, which has resulted in linking 50 gel spots to their genes (or open reading frames) and another 45 to specific regions of the chromosome awaiting the availability of DNA sequence information. Communication of information from the scientific community resulted in additional identifications and regulatory information. To increase accessibility of the database it has been placed in the repository at the National Center for Biotechnology Information (NCBI) at the National Library of Medicine under the name ECO2DBASE. It will be updated twice yearly. This edition of the gene-protein database is estimated to contain entries for one-sixth of the protein-encoding genes of E. coli.


Workshop on two-dimensional gel protein databases.

A workshop on two-dimensional gel electrophoresis (2-DE) protein database, organized by the Committee on Data for Science and Technology (CODATA) of the International Council of Scientific Unions Task Group on Biological Macromolecules, was held at the CODATA Secretariat in Paris on March 9, 1992. Eleven scientists from eight different countries represented various aspects of 2-DE analysis--namely, cellular protein database development and protein microsequencing methodologies. The purpose of the workshop was to explore means of integrating the rapidly expanding body of information on 2-DE resolved proteins from different laboratories. A major proposal emanating from the workshop was the establishment of an intermediary or "relational" 2-DE gel protein database. This intermediary database, which would catalogue pertinent information on 2-DE resolved proteins (experimental source, 2-DE loci, biological information, etc.) could be an adjunct to, and accessed through, the existing international protein sequence databanks. It would function as a pointer for researchers to the individual 2-DE protein databases where primary and more specialized 2-DE data would be housed.


The human keratinocyte two-dimensional gel protein database (update 1992): towards an integrated approach to the study of cell proliferation, differentiation and skin diseases.

The master two-dimensional gel database of human keratinocytes currently lists 2980 cellular proteins (2098 isoelectric focusing, IEF; and 882 nonequilibrium pH gradient electrophoresis, NEPHGE) many of which correspond to posttranslational modifications. About 20% of all recorded proteins have been identified (protein name, organelle components, etc.) and they are listed in alphabetical order together with their M(r), pI, cellular localization and credit to the investigator(s) that aided in the identification. Also, we have listed 145 microsequenced proteins that are recorded in this database. As an aid in localizing the polypeptides we have included blow-ups of the master images (IEF, NEPHGE) displaying all the protein numbers. In the long run, the master keratinocyte database is expected to link protein and DNA sequencing and mapping information (Human Genome Program) and to provide an integrated picture of the expression levels and properties of the thousands of proteins that orchestrate various keratinocyte functions both in health and disease.


Microsequences of 145 proteins recorded in the two-dimensional gel protein database of normal human epidermal keratinocytes.

Microsequencing of proteins recovered from two-dimensional (2-D) gels is being used systematically to identify proteins in the master human keratinocyte 2-D gel database. To date, about 250 protein spots recorded in human 2-D gel databases have been microsequenced and, of these, 145 are recorded in the keratinocyte database under the entry partial amino acid sequence. Coomassie Brilliant Blue-stained protein spots cut from several (up to 40) dry gels were concentrated by elution-concentration gel electrophoresis, electroblotted onto PVDF membranes and digested in situ with trypsin. Eluting peptides were separated by reversed-phase HPLC, collected individually and sequenced. Computer search using the FASTA and TFASTA programs from Genetics Computer Group indicated that 110 of the microsequenced polypeptides shared significant similarity with proteins contained in the PIR, Mipsx or GenEMBL databases. Only 35 polypeptides corresponded to hitherto unknown proteins. Peptide sequences of all 145 proteins are listed together with their coordinates (apparent molecular weight and pI) in the keratinocyte database.


Mouse liver protein database: a catalog of proteins detected by two-dimensional gel electrophoresis.

Alterations in the abundance or structure of mouse liver proteins are being studied using two-dimensional gel electrophoresis (2-DE) to build a database of protein changes correlating with exposure to ionizing radiation or toxic chemicals. Thus far, studies have included the analysis of proteins from the offspring of exposed parents or from the exposed individuals themselves. In order to characterize and identify proteins found altered by such exposures, sex- and strain-related differences in protein patterns have been analyzed, and the subcellular locations of a large portion of the mapped proteins have been determined. As part of these studies, data are collected and stored using a variety of computer hardware and software tools that allow the accumulation of information on the origin of samples, gel identification, experiment description, and protein similarities and differences. This accumulation of information constitutes the mouse liver protein database. Relational database software is used to tie the different facets of the database together so that the results of a variety of experiments can be compared and interrelated. The database optimizes the information obtained from 2-DE gel sets by allowing use of the data for many purposes, including monitoring of gel resolution to ensure the collection of high quality data and correlation of protein effects induced by different agents. This first edition of the Argonne National Laboratory mouse liver protein database lays the foundation for future work and communication that should elucidate the significance of observed protein effects as possible markers of exposure to toxic agents.


Human liver protein map: a reference database established by microsequencing and gel comparison.

This publication establishes a reference human liver protein map obtained with immobilized pH gradients. By microsequencing, 57 spots or 42 polypeptide chains were identified. By protein map comparison and matching (liver, red blood cell and plasma sample maps), 8 additional proteins were identified. The new polypeptides and previously known proteins are listed in a table and/or labeled on the protein map, thus providing a human liver two-dimensional gel database. This reference map can be used to identify protein spots on other samples such as rectal cancer biopsies.


Inhibition of lipid deposition in the hypercholesterolemic rat by clentiazem, a calcium channel blocker.

We studied the effects of clentiazem, a calcium channel blocker (1) on the accumulation of lipid in the aorta, (2) on the level of plasma lipids, and (3) on the number of adherent intimal monocytes and foam cells. Seventy Wistar rats were assigned to one of the following groups: (1) regular diet, (2) an atherogenic diet consisting of regular chow with 2% cholesterol, 1% cholic acid, and 0.5% thiouracil (CCT), (3) CCT supplemented with 5 mg/kg/day clentiazem, and (4) CCT with 25 mg/kg/day clentiazem. Animals were sacrificed after 6 or 12 weeks of diet. Aortas were studied by light microscopy after staining with oil red O (ORO) and/or hematoxylin. ORO staining was quantified in both abdominal and thoracic regions of the aorta. The aortas of the clentiazem groups demonstrated significantly less ORO staining than CCT diet controls in thoracic aorta after 6 weeks and abdominal aorta after 12 weeks. There was no significant difference in the plasma lipid concentrations. The clentiazem-treated groups had fewer numbers of adherent monocytes and foam cells. We conclude that clentiazem inhibits lipid deposition in cholesterol-fed rats without lowering plasma lipid concentrations and that the number of intimal monocytes and foam cells is decreased in the presence of this calcium antagonist.


Quantitative alteration of some aortic intima proteins in fatty streaks and fibro-fatty lesions.

Proteins from grossly and histologically normal human aortic intimas and human aortic intima with fatty streaks or fibro-fatty lesions were extracted with 9 M urea mixture. Protein extracts were mixed with an internal absorbance calibrator (carbonic anhydrase) and subsequently separated by two-dimensional gel electrophoresis, silver stained, and quantitated by a laser beam densitometer. The vascular-origin proteins actin, tropomyosin-like proteins, tubulin, glycoprotein G35, and two myosin light chains were present in the highest amounts in normal aortic intima (27-year-old male). Quantitation of vascular-origin proteins in aortic intima with a fibro-fatty lesion from the same subject showed a slight decrease in relative amount of these proteins as compared to the normal intima. Several polypeptides (P15, P18, P60, P110b) and plasma-derived proteins not observed in the normal intima were found in fibro-fatty lesion (albumin, haptoglobin beta-chain, fibrinogen beta-chain, alpha 1-HS-glycoprotein). Other proteins which were present in very low amounts in the normal intima (transferrin, alpha 1-antitrypsin, apolipoprotein A-1, P56, P190) were found to be major proteins of intima with fibro-fatty lesion. Differences in relative amount of plasma-derived and vascular-origin proteins between normal intima and intima with fatty streaks, studied in a large number of specimens from 38 thoracic intimas and 18 paired abdominal intimas (16-34 years old) were less prominent. Statistically significant increases of the albumin/actin ratio were found in fatty streaks as compared to paired normal intimas as well as in the mean value of albumin/actin ratio in the group of fibro-fatty lesions (mean = 6.1) as compared to the group of fatty streaks (mean = 1.7) or normal intima (mean = 0.7). Several lesion unique proteins were observed; however, the frequency of the occurrence of these proteins in 41 specimens with lesion was low. No significant differences were observed in intima protein pattern and quantities of selected intima proteins between paired thoracic and abdominal aortas.


Glucose and glucose analogs modulate collagen metabolism.

Patients with diabetes often develop complications involving collagen-containing connective tissues. Previous in vitro studies have demonstrated that glucose inhibits collagen fibril formation and subsequent cross-linking. Collagen with diminished cross-linking is more susceptible to collagenolytic degradation. This may underlie the decreased collagen levels. To test this hypothesis, D-glucose and its two analogs, L-glucose and 2-deoxy-D-glucose, were used in chick calvaria organ cultures to examine parameters of collagen metabolism. L-Glucose is not used by the cell and functions as an extracellular glucose-like molecule, while 2-deoxy-D-glucose inhibits normal D-glucose uptake by blockading the glucose transport mechanism. Each of these three sugars had the ability to inhibit collagen fibril formation. D-Glucose stimulated collagen synthesis; L-glucose had no effect; and deoxyglucose inhibited collagen synthesis. D-Glucose was able to reverse the inhibitory effect of deoxyglucose. D-Glucose did not change levels of degradation of newly synthesized collagen while both L-glucose and deoxyglucose stimulated collagen degradation. When glucose transport was inhibited by deoxyglucose, collagen degradation was further enhanced. We suggest that decreased collagen levels in the connective tissues of diabetics may result from a combination of inhibition of collagen fibril formation and subsequent cross-linking, as well as increased collagen degradation.


Microvascular changes in rat glomeruli as a consequence of small differences in selenium exposure.

This paper evaluates the effect of small differences in selenium exposure, within the safe range, on the glomerular vascular tufts of rats fed high-sucrose diets. In the first experiment male Wistar rats were housed in galvanized cages and were provided sucrose-based diets to induce a mild chronic insult to the microcirculation. One group of rats received the diet prepared to contain 0.10 mg Se/kg and another group 0.21 mg Se/kg. To assure that the galvanized metal cages were not influencing the results of the experiment this protocol was repeated in a second experiment wherein rats were housed in stainless steel cages. The levels of Se used supported normal activity of the long-term indicator of Se sufficiency, erythrocyte glutathione peroxidase. In both experiments rats fed diets containing 0.21 mg Se/kg had larger Bowman's capsules (P < 0.01) and vascular tufts (P < 0.01). Vascular tufts from these rats also contained a higher proportion of open capillary lumen (P < 0.01), contained less cytoplasmic and extracellular material (P < 0.001), and had larger nuclei (P < 0.001) than those fed 0.10 mg Se/kg. A third study was designed to determine if the selenium-dependent differences in nuclear size were indicative of this being a site of incorporation. Year-old rats subjected to the same protocol as those in the second experiment were given 75Se, by injection into the femoral vein, to label the sites of incorporation. Glomeruli were purified and subjected to subcellular fractionation. Ninety percent of the radioactivity was associated with the crude nuclear fraction. Purification of the crude nuclear fraction demonstrated that the radioactivity was associated with the nuclei.


The study of G6PD in erythrocyte and lens in senile and presenile cataract.

The G6PD activity of erythrocytes in 113 male patients with senile and presenile cataract and 86 controls, and G6PD activity of lens in 30 patients with senile cataract and 42 controls were reported. The cataractous group had higher frequency of G6PD deficiency and lower average G6PD level in erythrocytes and lenses, but without statistical significance. The frequency of G6PD deficiency of erythrocytes in presenile cataractous group was higher than that of senile cataractous group but with no statistical significance too. However, the average G6PD level of erythrocytes in presenile cataractous group was lower than that of senile cataractous group and with statistical significance (P < 0.05). The G6PD activity of lenses only presenile in the cortex and have a positive correlation with that of erythrocytes. There was a case with deficiency of G6PD both of erythrocytes and cataractous lenses in both eyes. The results indicate that the deficiency of G6PD might be one of the cataractous pathogenetic factor for presenile cataract. Measurement of G6PD activity of erythrocytes among population might be of significance in finding the risk factor for cataract.


Purification of bovine interphotoreceptor retinoid-binding protein and its uveitogenicity in Lewis rats.

Interphotoreceptor retinoid-binding protein, IRBP, not only functioning as a shuttle to carry the retinoid between photoreceptor cells and pigment epithelium, but also inducing experimental autoimmune uveoretinitis (EAU), was purified by ConA Sepharose affinity chromatography from the fractions containing IRBP obtained in the course of ion-exchange chromatography by which the bovine retinal S-antigen was purified. This much simplified method allows more rapid purification of the two kinds of protein. EAU was successfully induced with injecting 50 micrograms of IRBP emulsified with Freund's complete adjuvant into the right hind footpads of Lewis rats. It was characterized by panophthalmia or endophthalmia with the severest damage in the posterior retina. Lymphocytes, mononuclear and polymorphonuclear cells were found to be the inflammatory cells of infiltration, with lymphocytes being predominant.


Epidemiology of glaucoma in Asia-Pacific.

Primary open angle glaucoma is the second most important cause of permanent blindness in the Asia Pacific region. Thus it is very important to identify epidemiological and other risk factore which are associated with open angle glaucoma. The risk for glaucoma optic nerve damage increases with the age and with the level of the intraocular pressure. In this paper, I will highlight our study of several risk factors for development of the open angle glaucoma like (1) elevated intraocular pressure, (2) myopia, (3) suspicious large optic disc cup, (4) cupping with disc haemorrhages and (5) nerve fibre defect. The general and systemic conditions which are implicated as risk factore are (1) family history of glaucoma, (2) increase in age, (3) diabetes mellitus, (4) cardio vascular conditions like central retinal vein occlusion etc. (5) the endocrine disorders with increased thyroid and increased cortico steroids responsiveness in patients with glaucoma will be discussed.


Complications and management of the filtration bleb.

Filtration surgery is the commonest operation performed for closed angle or open angle glaucoma when medical treatment or laser trabeculoplasty has failed to control the intraocular pressure. It is characterized by the formation of an artificial drainage fistula between the anterior chamber and subconjunctival space. The successful operation is evidenced by the appearance of a subconjunctival filtration bleb which in turn depends on the patency of this pathway. Despite numerous modification, the procedure trabeculectomy first described by Sugar in 1961 and later on popularized by Watson and Cairns in 1968 is the most popular filtration surgery performed nowadays. It is a safe, relatively easy operation which carries a success rate of around 76% to 84% with a small complication rate. Repeat filtration surgery, however, is often less successful, making a successful initial surgery critically important. A successful outcome of filtration surgery can be enhanced by preoperative preparation, meticulous technique with modification for individual case, and early identification and prompt treatment of the complications arisen.


Advances in management of retinoblastoma.

Retinoblastoma is a highly malignant intraocular tumor of children that requires accurate diagnosis to prompt treatment. This article reviewed clinical, pathological and follow-up data on 1 147 cases of retinoblastoma registered in Japan from 1975 to 1982. It is obvious that the prognosis of children with retinoblastoma has improved remarkably in recent years. The current advances in the management of the retinoblastoma were discussed.


The prevention of blindness--past, present and future.

Prevention of blindness is the most important aim of ophthalmology. Prevention of blindness is related to many factors. It is related to many factors, such as science and technology, economy and social behavior. There are worldwide activities by WHO, NGOs and other functions to promote the prevention of blindness in the world. More than 90% of blind population lives in developing world. Cataract is the top causes of blindness which is curable. Onchocerciasis is an endemic disease in west Africa and central America. Onchocerca Control Project (OCP) was formed in 1974 under WHO for the control of oncocerciasis by the funds of developed countries. The control of vector (simulium) as well as new drug are giving the the project the prospect of success in eradicating the disease, thus preventing the blindness by diseases. The situation on blindness by trachoma, childhood blindness, glaucoma, diabetes will be discussed. The progress of molecular genetics of eye disease may open the gate for prevention of blindness by these disease in future.


The electrophysiology in idiopathic senile macular hole.

Of 12 patients with idiopathic senile full-thickness macular hole, 3 had bilateral involvement, 9 had monocular macular hole. Flash ERG and pattern VEP were performed in the bilateral eyes of all patients. The abnormal rate of the pattern VEP was 93.3% when we used 15' checkboard stimulus, the changes of the VEP appeared as delayed latencies, reduced amplitudes or malformation of P100. The abnormal rate of the flash ERG was 53.3%, showing primary characteristics of reduced amplitudes of cone response b-wave. There was statistically significant difference between the abnormal rates of the VEP and the ERG (P < 0.05). The halo diameters of the macular hole were significantly related to the latencies of P100 (P < 0.01), but there was no correlation between the hole diameter and the latencies of P100. In 9 fellow eyes which did not form macular hole, 3 eyes had the abnormal pattern VEP, including one eye having formed macular cyst. The results show that, in idiopathic senile macular hole, the pattern VEP provides more functional information than does the ERG, and prompts the importance of close follow-up of fellow eye.


Use of perfluorocarbon liquids in complicated retinal detachments.

We now have an additional tool to help in managing complicated retinal detachments. We look forward to the day when we can leave the liquid without having to remove it because of the possibility of ocular complications.


Branch retinal vein occlusion and its management.

The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the perifoveolar arcades. Retinal and capillary vasoproliferation with or without intraretinal or preretinal membrane formation are common sequelae, where inner retinal ischemia is extensive and vitreous hemorrhage is often a distinct threat to vision. Treatment of the sequelae of vein occlusion are largely centered on laser photocoagulation to diseased retina to limit fluid accumulation and abolish preretinal and papillary neovascularization. Vitrectomy and retinal detachment procedures are occasionally required in patients with uncontrolled vitreous hemorrhage and retinal membrane formation which threatens the integrity of the macula. A small proportion of patients with vein occlusion subsequent to vasculitis require medical therapy.


Detection of gene alteration for color vision defects by polymerase chain reaction.

According to the fact that the abnormalities of visual pigment genes were always involved in the changing of the exon 5, two oligonucleotide primers were designed to amplify the exon 5 of red pigment gene and green pigment gene. After electrophoresis of the PCR products digested with Rsal or Sau3A, the DNA fragments from the exon 5 of red pigment gene (RPG) and green pigment gene (GPG) were separated since there are different restriction endonuclease sites. On the other hand, we analyzed the exon 5 related fragment by Southern blot hybridization with probe out of the 3' end of the fourth intron of green pigment gene. The results of PCR are consistent with nucleic acid hybridization. PCR technique will be of value in prenatal evaluation and genetic counselling.


[A decrease in cardiac sensitivity after ischemia to a change in the extracellular concentration of calcium ions].

Reperfusion of the heart 30 min. after ischemia causes slight recovery of contractility and content of macroergic compounds in the myocardium tissue. Recovery of perfusion by the hypercalcium medium (0.05 mol/l) improves metabolism of the myocardium 30 min after ischemia. However, further perfusion by solution with physiological content of Ca2+ is followed by the development of the myocardium contracture, essential decrease in extracellular concentration of ATP and phosphocreatine. An increase in the extracellular sodium concentration and addition of macroergic compounds (ATR, phosphocreatine) adenosine, when reperfusing the heart by hypocalcium solution, improve the postischemic state of the myocardium and protect it from injuries during the following recovery of physiological Ca2+ content in the extracellular medium.


[The topological characteristics of rat myocardial reactivity to noradrenaline, acetylcholine and a change in the electrostimulation frequency].

Dose-dependent effects of noradrenaline (10-7-10-6M), acetylcholine (10-8-3x10-6M) and stimulation rate (0.2-2.0 Hz) were obtained in experiments on myocardium preparations of the right and left atria and ventricles in rat. Three types of topological differences of the rat myocardium reactivity were observed: between the atria and ventricles (A/V), between the right and left atria and ventricles (R/L), between the right atrium (RA) and other cardiac chambers. A/V differences were most pronounced in the reactivity to acetylcholine (the atria were more reactive), the highest R/L differences were observed in the reactivity to noradrenaline (the myocardium of the right chambers was more reactive). RA reactivity greatly exceeded reactivity of other myocardial preparations to all three test influences. Topological peculiarities of chrono-inotropism permit supposing, that inotropic effects of rate changes in vivo are able to compensate, to some extent, the regional nonuniformity of cholin- and adrenergic regulatory inotropic effects.


[The anticonvulsive action of the intranigral administration of the delta sleep-inducing peptide].

It is shown that injection of delta sleep-inducing peptide (DSIP) into the substantia nigra reticular part (SNrp) suppresses generalized convulsive activity induced in rats by picrotoxin and corazol injection but exerts no influence on the strichnine-induced seizures. The analogous DSIP injection causes the antiepileptic action in rats kindled through picrotoxin injections. The DSIP intranigral anticonvulsant action is blocked by naloxon and enhanced by haloperidol and yohimbin. It can be concluded that DSIP anticonvulsant action may be realized due to activation of SNrp-dependent opioid mechanisms and suppression of dopaminergic ones.


[The mechanisms of the formation of cardiogenic afferent effects after the development of local immune damage to the heart].

Sensitivity of cardiac receptors to several substances after local immune heart damage and the nature of cardiogenic influences on the circulation were studied in acute experiments o anesthetized dogs. The depressor reflexes from the heart were shown to disappear during 30 min. after immune heart damage, and vagal afferent impulse activity decreased. After immune heart damage, cardiac sympathetic afferent fibres were more sensitive to endogenous biological substances than to vagal ones. The sympathetic cardiac afferent system is found to be more sensitive to chemical agents, which is a decisive factor in formation of cardiogenic influences on the circulation during pathological processes in the heart.


[The effect of different gas mixtures under increased pressure on the self-stimulation reaction of rabbits].

Self-stimulation of rabbits in heliox at high pressure was decreased. That effect was potentiated by rapid compression. Addition of 2% or 6% nitrogen to heliox exerted no influence on the self-stimulation behavior.


[The central mechanism of the immunomodulating action of vasopressin and its structural analogs].

It is shown that the effect of neuropeptides depends on the dose and their structure. Considerable immunostimulation is observed after administration of [8-arginine]vasopressin and des-9-glucine-[8-arginine]vasopressin as against the control. This stimulation is prevented by the preliminary heloperidol blockade of dopaminergic receptors, i.e. it is dopamine-dependent. At the same time, injection of tetrapeptide vesopressin-(2-5) induces deep immunosuppression in all the applied doses. The peptide immunosuppression is shown to be a result of interaction with another neuromediator (serotoninergic); it has no effect under preliminary cuproheptadine blockade of C-2 serotonin postsynaptic receptors. The immunomodulating effect of the neuropeptides studied is central one and is realized via the hypothalamus-hypophysis complex.


[An analysis of the mechanism of the effect of intragastric calcium and magnesium on the release of gastrin and insulin in dogs].

The experiments have been carried out on four intact awake dogs to study the influence of intragastric introduction of deionized water, 5 mmol/l of calcium and magnesium chloride solutions in a dose of 3 ml/kg on release of gastrin and insulin into blood. It is stated that during the first 4 min after infusion of deionized water the release of gastrin decreases by 89 +/- 32 conventional units (c.u.), CaCl2 exerts a more pronounced inhibitory effect (168 +/- 36 c.u.), while MgCl2, on the contrary, increases the gastrin release by 398 +/- 92 c.u. Atropin (0.03 mg/kg, subcutaneous injection, 10 min before infusion) absolutely takes away the gastrin-stimulating effect of magnesium, but it has almost no influence on the gastrin-inhibitory effect of calcium. The latter can be taken away by 62% by ornid (5 mg/kg subcutaneously, 20 min before infusion). Preliminary anaesthesia of the stomach mucosa by trymecain or novocain absolutely remove the effect of both calcium and magnesium. Insulin release remained significantly unchanged in any series of experiments.


[The ultrastructural changes in the glomeruli and juxtaglomerular apparatus at different periods of endotoxic shock].

It is shown that after endotoxin injection the ultrastructural changes in the glomeruli can favour development of the acute renal insufficiency. In the initial and intermediate periods of the endotoxin shock the granular and agranular forms of juxtaglomerular cells hyperfunction, respectively, are revealed as well as an increase of renin activity in plasma. At the stage of the late endotoxemia ultrastructural alterations are stabilized. The juxtaglomerular cells synthesize and accumulate secretory granules, but renin activity in plasma decreases almost to the initial level.


[The effect of long-term bed-rest head-down-tilt hypokinesia on the functional properties of the human neuromuscular apparatus].

An influence of 120-days antiorthostatic (-6 degrees) hypokinesia (ANOH) on the functional properties of human m. triceps surae (TS) was investigated. After ANOH the maximal force and the maximal voluntary contraction of TS decreased on the average by 45.5% and 33.7%, respectively, and the maximal twitch response force--by 36.7% (P < 0.05-0.01). The value of force deficit increased on the average by 60.2% (P < 0.001), while a relative increase of the TS force contraction decreased in response to pair irritation (P < 0.05-0.01) as well as the velocity properties of TS after ANOH (P < 0.05-0.001). The rate of absolute (c.u.) tension development fell significantly in response to electrical nerve irritation and during voluntary contraction, while the force-velocity muscle properties according to relative (%) parameters remained unchanged. The fatiguability index of TS constituted the average 0.61 +/- 0.02 after ANOH as against 0.80 +/- 0.03 prior to it (P < 0.05). It is postulated the alterations of contractile properties of TS are due both to atrophic processes, muscle length change, condition of sarcoplasmic reticulum and to changes in the state of the central nervous system.


[The dynamic accumulation of a low-molecular physiologically active depressor factor and its biological effects in hemorrhagic shock].

A low-molecular factor (800-1000 D) was isolated from the blood serum of dogs using selective ultrafiltration. That factor was taken in various terms of the hemorrhagic shock development. Biological activity of the factor was determined in experiments on isolated hearts of dogs and lymphoid cells. It is found that the above factor decreases the contractile function of the isolated heart, disturbs energy formation, inhibits the antibody-forming function of the spleen as well as possesses a cytolytic effect on lymphocytes of the peripheral blood lympho-nodes and thymus.


[An analysis of the scientific publications of the A. A. Bogomolets Institute of Physiology of the Academy of Sciences of Ukraine].

Scientific publications from three sectors of the Institute have analyzed for the period since 1979 till 1988 inclusive. The analysis is based on data of annual reference books Science Citation Index (SCI) and lists of publications of each researcher of the Institute. It is shown that with almost equal numerical strength of researchers and similar number of publications the sector of molecular physiology contributed 43.6% to cited works 48.2% of these works are included into database of SCI. Such indices for the sectors of neurophysiology and physiology of visceral systems accounted for 33%, 33.4% and 23.4, 18.4% respectively. It is of interest that 47.5% of references to the cited works of the molecular physiology sector were made by foreign scientists and self-citation constituted 17.4%, while for the other sectors such indices had a reverse relationship. The problem on objectification of estimation of research is under discussion.


[The action of specific antimembrane antibodies on the tonic tension and contractile phases of the heart muscle in rats].

Antibodies specific to rat myocardial sarcolemma inhibit phasic contractions and promote an increase in tonic tension of isolated strips of the cardiac muscle in rat. These results indicate that antibodies induce accumulation of intracellular free Ca2+. Analysis of the authors' data and those from literature suggests that specific antibodies inhibit Na(+)-K(+)-pump activity of the cardiac muscle in rat. This conclusion is confirmed by analogy of effects of ouabaine, the well-known inhibitor of Na(+)-K(+)-pump, on the rat cardiac muscle.


[The prevention of the development of myocardial contracture in the "calcium paradox" by action on Na-Ca metabolism].

The effect of artificial high sodium gradient on the rate of the myocardium contracture development during "calcium paradox" was studied in the experiments on the isolated heart of Langendorf-perfused rats. It is stated that artificial creation of a high sodium gradient decreases the rate of the myocardium contracture development. Exogenous nucleotides, activators of Na, K-ATPase, and their precursors intensified the protective action of the hypersodium medium. Phosphocreatine (100 mmol/l) had no protective effect during the "calcium paradox". However, under conditions of the high sodium gradient phosphocreatine efficiently prevented development of the contracture during the "calcium paradox". It is important to note that under analogous conditions creation of high osmosity of the solution adding 12 mmol/l of saccharose does not protect the heart from development of the myocardium contracture.


[The effect of an electromagnetic field on the indices of conditioned reflex activities in rats].

The formation of defensive conditional reflexes in rats exposed to 10 cm electromagnetic field of different power densities during 4-months-long experiment has been studied. Stability of conditional reflectory reactions for the whole period of exposure is shown. The after-exposure period is characterized by the prevalence of excitatory processes.


[A new method for cannulation of the common bile duct in an experiment].

The proposed method of common biliary duct cannulation is simple, easily performed and permits studying bile hydrodynamics biligenesis for a necessary time. Tightness of the system is completely preserved after removal a choledochostomical tube. Walls of the invaginated stump of the cystic duct are swiftly abated as a result of hydrostatic pressure and cover its gap. The presence of purse string kapron suture in a stump orifice creates an obstacle to deinvagination. Good reparation properties of serous and subserous membranes, covering the biliary duct, promote rapid closing of stoma. Effectiveness of the proposed method of common biliary duct cannulation by means of the invaginated stump of the cystic duct is confirmed by the smooth postoperative course and absence of a biliary fistula after the tube removal.


[The hordox correction of excessive proteolytic activity and the sialic acid content of the blood under an emotional influence on rabbits].

The influence of the acute emotional stress on the activity of proteolysis and content of free sialic acids in the blood under usual conditions and after the preliminary introduction of gordox has been studied in the experiment on rabbits. It is established that the parallel rise of their levels under stress reflects degradation of glycoproteins and fragments containing sialic acids under the influence of the increased activity of proteinases. Gordox, together with the inhibition of excessive activation of proteolysis, prevents the rise of the level of sialic acids under the influence of the stress action. The conclusion is made that it is expedient to use inhibitors of proteolytic enzymes for prevention of cellular lesions in stress.


The effect of retinal autoantigens and their peptides on the inhibition of experimental autoimmune uveitis.

Experimental autoimmune uveitis is an immune-mediated inflammation of the retina and uveal tract. Such inflammation can be induced in eyes of experimental animals by inoculating them with retinal autoantigens. This animal model of uveitis closely resembles idiopathic uveitis in humans and lends itself ideally for the study of mechanisms involved in the aetiopathogenesis of uveitis and for the evaluation of methods used to control or prevent immune-mediated intraocular inflammation. In this study we used the retinal proteins S-antigen, interphotoreceptor retinoid binding protein and some synthetic peptides of S-antigen to modulate the immune response of Lewis rats. Following immunomodulation these animals did not develop uveitis when challenged with the retinal proteins. The discovery of small, non-pathogenic peptides of retinal antigens that down-regulate the immune response has relevance in developing strategies for immune intervention in human uveitis.


Sympathetic ophthalmia: visual results with modern immunosuppressive therapy.

Sympathetic ophthalmia is a rare bilateral panuveitis that follows penetrating injury to one eye. The use of systemic corticosteroids has transformed the prognosis, and good acuity in the sympathizing eye can now be achieved. The use of immunosuppressive drugs, such as cyclosporin and azathioprine, in combination with the steroids, allows control of the intraocular inflammation at a much lower steroid dose, with concomitant reduction in the systemic side effects that accompany the use of systemic steroids.


Passing the DVLC field regulations following bilateral pan-retinal photocoagulation in diabetics.

Twenty-one diabetics who had had bilateral retinal panphotocoagulation preserving a visual acuity sufficient to pass the Driver and Vehicle Licensing Centre (DVLC) requirements were assessed with regard to their ability to satisfy the DVLC visual field requirements. Of the 19 patients treated with the laser alone, 17 met the requirements for a licence to drive a private vehicle. The use of the Xenon photocoagulator and large total burn area following laser was found to be associated with an increased risk of DVLC field test failure. Adequate PRP with 200 micron burns appeared to induce neovascular regression and be compatible with passing the DVLC field regulations in many patients. Panphotocoagulation of patients with early proliferative retinopathy using 200 micron burns does not appear to jeopardise a driving licence. Guidelines for laser treatment in diabetic retinopathy aimed at preserving the driving field are presented.


Spontaneous relieving retinotomies in diabetic silicone filled eyes.

We describe in six patients the delayed occurrence of inferior tractional retinal detachments following epiretinal reproliferation 4 to 5 months after vitrectomy and silicone oil tamponade for diabetic related retinal detachments. The epiretinal traction was spontaneously relieved by the occurrence of large inferior tension breaks which subsequently enlarged and coalesced to form retinotomies. This process appears to be relatively benign as it remains limited to the peripheral retina, and in all six patients the posterior retina has remained attached for a minimum of 12 months follow up, with improved central visual acuity.


Criteria for intravitreal antibiotics during surgical removal of intraocular foreign bodies.

Published opinion supports the early use of prophylactic antibiotics soon after presentation of a potentially contaminated intraocular foreign body (IOFB) in the posterior segment, preferably within 12 hours of trauma when the visual acuity is still good. Recommended treatment includes topical, subconjunctival, parenteral and especially intravitreal antibiotic therapy to reduce the chance of endophthalmitis. Intravitreal therapy should include gentamicin with vancomycin or clindamycin to cover Bacillus spp., since this organism is responsible for half the endophthalmitis cases and produces beta-lactamase giving resistance to penicillins and cephalosporins. Intravitreal therapy is important because systemic and topical antibiotics do not penetrate the globe in sufficient concentration to control a fulminant infection associated with damaged tissue. Early therapy is essential, as delaying treatment until endophthalmitis occurs is less likely to save useful vision. All vitreous aspirated, plus pus if present, and the IOFB should be cultured for bacteria and fungi to identify pathogens and gain antibiotic sensitivities. The prevention of IOFB-associated endophthalmitis requires early recognition of the IOFB and enthusiastic antibiotic therapy at the time of its removal.


Aqueous kinetics of sisomicin sulphate.

Sisomicin sulphate is a new-generation aminoglycoside with a broad spectrum of antimicrobial activity that includes Pseudomonas aeruginosa. It is superior to gentamicin against indole-negative Proteus and some resistant strains of Pseudomonas. The ocular pharmacokinetics of sisomicin have not been explored. We used the agar diffusion technique of microbial assay to determine the aqueous penetration and bioavailability of a subconjunctivally placed standard dose of 20 mg/0.4 ml of sisomicin sulphate in 20 human volunteers undergoing elective cataract surgery. A peak concentration of 16.4 mg/l was found in the aqueous humour 78 minutes after injection, which is 65 times the minimum inhibitory concentration for Pseudomonas. The antibiotic was bioavailable up to 1203 minutes after injection in a concentration of 0.9 mg/l, which easily covers the minimum inhibitory concentration of Staphylococcus aureus and Pseudomonas. The antibiotic disappears from the aqueous humour at the 1434 minute interval (approximately 24 hours). The elimination half-life (t1/2 of sisomicin was determined to be 5.16 hours (K = 0.134/hour) and the aqueous clearance was 2.87 microliters/min.


Stereopsis and ageing.

This study reports the prevalence of defective stereopsis in an elderly population. Of 728 individuals over the age of 65 who attempted a Frisby stereotest, only 27% had full stereopsis and 29% had no stereopsis. In the elderly population defective stereopsis is a common finding in the absence of any other ocular morbidity. The prevalence of defective stereopsis increased with age. This finding was noted as a part of a survey of eye health of elderly people living in an inner city. The finding was not associated with any symptoms. The significance of this finding is discussed.


Retinopathy of prematurity: a prospective study. Review at six months.

A cohort of infants of birthweight < or = 1700 g studied prospectively for retinopathy of prematurity (ROP) has been reviewed at 6 months corrected age and the findings related to the neonatal data. The overall incidence of strabismus was 6.4% (30/468), rising from 3.1% (7/229) without ROP to 29.2% (7/24) with stage 3. Strabismus and fusional ability were significantly related to presence and severity of ROP, and abnormal neonatal cranial ultrasound findings. Binocular visual acuity was measured in 340 infants between 20 and 40 weeks corrected age. Eight were subnormal, all due to neurological problems. For the remainder, despite falling within the normal range, there was a significant trend (p < 0.001) for lower acuities with increasing ROP severity. Cycloplegic refraction on 387 infants revealed, with increasing ROP severity: 1, a significant trend towards myopia; 2, increased magnitude of astigmatism; 3, alteration of the astigmatic axis; 4, increased incidence of anisometropia. For the first three categories there was an insignificant trend between no ROP and stage 2, reaching significance only between stage 2 and 3. The predominant axis of astigmatism in infants without ROP was between 60 degrees and 120 degrees, but with ROP there was a significant trend away from this direction.


The mersilene covered intraorbital implant.

The most widely used material for covering spherical intraorbital implants is sclera. Mersilene mesh is an alternative substance combining the advantages of permanent implant cover with low rates of infection and ready availability. We describe our experiences in the use of Mersilene mesh covered intraorbital implants in 14 patients. Our findings suggest that Mersilene mesh could be considered as a possible alternative choice of material for covering intraorbital implants.


The National Cataract Surgery Survey: I. Method and descriptive features.

The National Cataract Surgery Survey is a prospective cross-sectional survey of surgery for age-related cataract within the National Health Service. It is the first national study of cataract surgery in the United Kingdom providing clinical data. This is the first in a series of papers and describes a profile of the characteristics of patients admitted for cataract surgery that includes: demography, referral sources, presence of co-existing ocular pathology, level of visual impairment on admission and waiting time for surgery. A profile of the process of the surgical procedure for 1990 is also described: number of operations performed, type of admission, type of anaesthetic, cataract extraction and intraocular lens and the grade of surgeon performing the procedure.