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PubMed1977

A contribution to our knowledge of ginseng.

The Chinese people discovered ginseng and used it as a revitalizing agent since time immemorial. They are still the world's major consumers of this plant drug. The commercial product of ginseng comes from two species of the genus Panax in the family Araliaceae. These species are P. ginseng C. A. Meyer which is the source plant of the Chinese, Korean and Japanese brands of ginseng, and P. quinquefolius L., which is the source of American ginseng. Phytogeographically, ginseng demonstrates the classical bicentric pattern of plant distribution, with closely related species in eastern Asia and in eastern North America. Ecologically, ginseng is an undergrowth of hardwood mixed deciduous forest. It prefers the northern or the northeastern slope of a hill. Species of the genus Tilia are good indicators of the proper environmental condition for the growth of ginseng. Morphologically, ginseng is a perennial herb with fleshy root, a single annual stem bearing a whorl of palmately compound leaves, and a terminal simple umbel of small 5-merous flowers. The flowers are soon followed by pea-sized fruits developed from inferior ovaries. The fruits are red when ripe. Ginseng is propagated by seed. The commercial products of ginseng consist primarily of roots 2-20 years old. Within this age range, the older the root the higher the market value, provided they are grown in proper conditions. The methods of curing the roots change the color and shape of the products. Chinese ginseng is prepared from roots bleached, boiled, steamed, or sugared in curing. The cultural background for the uses of ginseng by the Chinese people is explained. Ginseng may be used alone in the form of tea, powder, or as a masticatory. It is also used in combination with other drugs of animal, mineral, or plant origin. Forty-two recipes are selected from Pen-ts'oa kang-mu and translated into English for the first time to show the various ways by which ginseng is used in traditional Chinese medicine. A systematic summary of the companion plant drugs of ginseng is presented in the form of a table, showing the distribution of the species in the plant kingdom. The scientific names of the species are given in full.

Agriculture↗
PubMed2025

Dual genetic loci and flavonoid metabolism orchestrate fruiting body coloration in Flammulina filiformis: a multi-omic roadmap for fungal pigmentation.

BACKGROUND: The fruiting bodies of macrofungi exhibit diverse coloration, traditionally attributed to melanin and carotenoid biosynthesis. This study is the first to reveal that flavonoids, rather than these classical pigments, are the predominant contributors to yellow pigmentation in the Flammulina filiformis. OBJECTIVE: To uncover the genetic basis and key regulatory genes involved in pigment formation in F. filiformis fruiting bodies, and to establish a model framework for studying color genetics in macrofungi. METHODS: Metabolomic profiling was conducted on yellow and white F. filiformis fruiting bodies to identify key pigment components. A segregating population was constructed, followed by integrated multi-omics analyses-including bulk segregant analysis (BSA), genome-wide association study (GWAS), and transcriptomics-to map regulatory loci and candidate genes. Functional roles were validated via genetic transformation and protein structural modeling. RESULTS: Flavonoid accumulation was identified as the biochemical hallmark of pigmented fruiting bodies. Genetic analysis revealed a dual regulatory mechanism: a qualitative locus governing pigmentation presence and a quantitative trait determining color intensity. Combined BSA and GWAS pinpointed a major locus, Ffcrs, within a recombination-suppressed region. Transcriptomic analysis identified two key regulators, Ffakr (a transcriptional activator) and Ffpal (encoding phenylalanine ammonia-lyase). Functional verification via transformation, structural modeling, and metabolite profiling in transgenic lines confirmed their essential roles in flavonoid biosynthesis and pigmentation. CONCLUSION: This study uncovers a flavonoid-based pigmentation mechanism in F. filiformis and elucidates a complex genetic architecture shaped by both qualitative and quantitative loci, providing a new paradigm for understanding pigment formation in macrofungi. The identified regulatory factors establish a molecular foundation for the precise manipulation of economically important pigmentation traits in edible mushroom.

Flavonoids↗
PubMed2001

From irreversibility to participation: towards a participatory foresight for the governance of collective environmental risks.

This paper presents a reflection on the introduction of methods and tools of "participative foresight" for scientific and technology policy as well as environmental policy fields. Future studies have recently made a comeback under the label of foresight. Future technology studies no longer claim to forecast the future, but are presented as a strategic tool for improving interaction between key actors and for anticipatory policy making. They can be defined as a "process by which one comes to a fuller understanding of the forces shaping the long term future which should be taken into account in policy formulation, planning and decision-making" [Foresight in Federal Government Policymaking, Futures Res. Quart. (1985) 29]. We discuss applications of this approach for perspectives on environmental policy and sustainable development. Foresight opens up the possibility of negotiating a new and more fruitful relationship or 'social contract' between science and technology, on the one hand, and society on the other. The focus has moved from merely scientific and industrial insights to social demand, thus emphasizing the importance of both the production and "supply" of innovation, and the "demand" as signaled in the views of citizens.

Decision Making↗
PubMed1995

Germination of myxospores from the fruiting bodies of Myxococcus xanthus.

Germination of myxospores from fruiting bodies of Myxococcus xanthus was examined under a light microscope as well as by analyzing the incorporation of [3H]uracil into the RNA fraction. Efficient germination was observed in 0.2% Casitone containing 8 mM MgSO4 and 1 mM CaCl2 at 30 degrees C. Under this condition, spherical myxospores were converted into rod-shaped vegetative cells within 5 to 6 h. The germination was severely inhibited in the presence of 1 mM phenylmethylsulfonyl fluoride, a protease inhibitor, indicating that a serine protease(s) is required for the myxospore germination. EGTA (1 mM) also completely blocked germination, indicating that Ca2+ plays an important role in myxospore germination. In 1% Casitone without added Mg2+ and Ca2+ or 0.2% Casamino Acids with 8 mM MgSO4 and 1 mM CaCl2, myxospores lost their refractility under a phase microscope, while no RNA synthesis took place within 6 h, as judged by the incorporation of [3H]uracil. A group of proteins were found to be specifically synthesized during an early stage of germination. In addition, a new major spore-associated protein with a size of 41.5 kDa became detectable in the spore shell fraction 3 h after germination. The present results demonstrate that myxospore germination occurs in at least two steps: the loss of myxospore refractility, followed by an outburst of metabolic activities. The first step can occur even in the absence of energy metabolism, while the second step was blocked by rifampin, EGTA, and protease inhibitors.

Amino Acids↗
PubMed2000

Persistence of Lactobacillus plantarum DSM 9843 on human tonsillar surface after oral administration in fermented oatmeal gruel. A pilot study.

The occurrence of Lactobacillus plantarum DSM 9843 on tonsillar scrapings was studied after single-dose administration. Six healthy volunteers gargled 100 ml of fermented oatmeal gruel containing 2 x 10(11) colony forming units (cfu) of Lb. plantarum DSM 9843 for 2 min and then swallowed it. Two healthy volunteers drank 50 ml fermented oatmeal gruel (containing 1 x 10(11) cfu of Lb. plantarum DSM 9843) mixed with 50 ml fruit juice, and in another experiment, 5 ml fermented oatmeal gruel (containing 1 x 10(10) cfu of Lb. plantarum DSM 9843) mixed with 95 ml fruit juice. Lb. plantarum DSM 9843 were found in tonsillar scrapings 4-8 h after intake of 2 x 10(11) cfu, for 5-8 h after intake of 1 x 10(11) cfu, and finally up to 4 h after intake of 1 x 10(10) cfu. On electron microscopy micrographs, short rod-shaped bacteria were visible 1 h after intake of the fermented oatmeal gruel, but not 2 h after intake. The results suggest that Lb. plantarum DSM 9843 possess an ability to adhere to tonsillar cells.

Administration, Oral↗
PubMed1998

An unusual parotid gland in the tent-building bat, Uroderma bilobatum: possible correlation of interspecific ultrastructural differences with differences in salivary pH and buffering capacity.

The tent-building bat, Uroderma bilobatum, is a small, frugivorous phyllostomid bat with a broad neotropical distribution. Generally found in humid forest, this bat lives in small groups that create daytime "roosts" from large leaves of a variety of tropical plants. Fruit eating engenders a variety of ecological and physiological challenges for bats, some of which could require adaptive features in their salivary glands. The parotid salivary glands of Uroderma bilobatum were prepared for transmission electron microscopy by using methods that have become standard for field work. The parotid gland is extremely unusual in structure. Although the secretory endpieces still produce serous granules with a complex substructure, they are modified into quasi striated ducts. Their basal folds, which are extensive, occasionally harbor some vertically oriented mitochondria, imparting a resemblance to striated ducts. Other evidence for the endpiece origin of these parenchymal components is a well-developed system of intercellular canaliculi, structures that never occur in bona fide striated ducts. The long but sparse intercalated ducts consist of two types of cells, each of which elaborates a modest number of secretory granules of differing substructure. Striated ducts are of conventional morphology, except that a few dark cells shaped like wine glasses are present in their walls. The striated duct cells produce no secretory granules, but their apical cytoplasm may contain some small, empty vesicles. Capillaries lie in longitudinal grooves in the base of the duct cells, an arrangement that might enhance electrolyte exchange. Excretory ducts consist of simple cuboidal epithelium composed of cytologically unspecialized cells that sometimes includes a dark cell. It was concluded that salivary glands could have a major role in adapting species to acquire nutrients from marginal sources, such as tropical fruits, which have a low protein and sodium content. The unusual parotid acinar cells in Uroderma bilobatum are discussed in the context of salivary pH and buffering capacity. Comparisons are made with four other bat species, including an insectivorous species with a salivary pH > 8.0 and a very high buffering capacity, an intermediate species, and a fruit bat with acidic-stimulated saliva and very low buffering capability. Such interspecific comparisons provide a foundation for hypothesizing that ultrastructural features of the acinar cell basolateral membranes and intercellular canaliculi correlate with differences involving Na/H+ exchangers and release of HCO3- and, thus, are associated with the species differences that are important to diet and nutrient acquisition.

Animals↗
PubMed2003

QTL analysis of morphological traits in eggplant and implications for conservation of gene function during evolution of solanaceous species.

An interspecific F(2) population from a cross between cultivated eggplant, Solanum melongena, and its wild relative, S. linnaeanum, was analyzed for quantitative trait loci (QTL) affecting leaf, flower, fruit and plant traits. A total of 58 plants were genotyped for 207 restriction fragment length polymorphism (RFLP) markers and phenotyped for 18 characters. One to eight loci were detected for each trait with a total of 63 QTL identified. Overall, 46% of the QTL had allelic effects that were the reverse of those predicted from the parental phenotypes. Wild alleles that were agronomically superior to the cultivated alleles were identified for 42% of the QTL identified for flowering time, flower and fruit number, fruit set, calyx size and fruit glossiness. Comparison of the map positions of eggplant loci with those for similar traits in tomato, potato and pepper revealed that 12 of the QTL have putative orthologs in at least one of these other species and that putative orthology was most often observed between eggplant and tomato. Traits showing potential orthology were: leaf length, shape and lobing; days to flowering; number of flowers per inflorescence; plant height and apex, leaf and stem hairiness. The functionally conserved loci included a major leaf lobing QTL ( llob6.1) that is putatively orthologous to the potato leaf ( c) and/or Petroselinum ( Pts) mutants of tomato, two flowering time QTL ( dtf1.1, dtf2.1) that also have putative counterparts in tomato and four QTL for trichomes that have potential orthologs in tomato and potato. These results support the mounting evidence of conservation of gene function during the evolution of eggplant and its relatives from their last common ancestor and indicate that this conservation was not limited to domestication traits.

Chromosome Mapping↗
PubMed2005

Ectopic expression of an FT homolog from citrus confers an early flowering phenotype on trifoliate orange (Poncirus trifoliata L. Raf.).

Citrus FT (CiFT) cDNA, which promoted the transition from the vegetative to the reproductive phase in Arabidopsis thaliana, when constitutively expressed was introduced into trifoliate orange (Poncirus trifoliata L. Raf.). The transgenic plants in which CiFT was expressed constitutively showed early flowering, fruiting, and characteristic morphological changes. They started to flower as early as 12 weeks after transfer to a greenhouse, whereas wild-type plants usually have a long juvenile period of several years. Most of the transgenic flowers developed on leafy inflorescences, apparently in place of thorns; however, wild-type adult trifoliate orange usually develops solitary flowers in the axils of leaves. All of the transgenic lines accumulated CiFT mRNA in their shoots, but there were variations in the accumulation level. The transgenic lines showed variation in phenotypes, such as time to first flowering and tree shape. In F(1) progeny obtained by crossing 'Kiyomi' tangor (C. unshiu x sinensis) with the pollen of one transgenic line, extremely early flowering immediately after germination was observed. The transgene segregated in F(1) progeny in a Mendelian fashion, with complete co-segregation of the transgene and the early flowering phenotype. These results showed that constitutive expression of CiFT can reduce the generation time in trifoliate orange.

Agrobacterium tumefaciens↗
PubMed2004

Alcohol intake and insulin resistance. A cross-sectional study.

BACKGROUND AND AIM: The development of insulin resistance is a critical step in the pathogenesis of type 2 diabetes. The effect of alcohol intake on insulin sensitivity/resistance is not well defined. The aim of this study was to examine the association between alcohol intake and insulin resistance in a sample of middle-aged men and women with data on a wide range of potential confounding factors, including diet. METHODS: We performed a cross sectional study involving a group of 1018 men and women, sampled from 17 general practice lists in the South of Ireland, with a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and a food frequency questionnaire and provided fasting blood samples for analysis of glucose and insulin. Insulin resistance was estimated on the basis of fasting glucose and insulin, using the glucose homeostasis model (HOMA scores). Insulin resistance was defined as the upper quartile of the HOMA scores. RESULTS: We found evidence of a U-shaped relationship between alcohol intake and insulin resistance fitted as a continuous variable (HOMA scores) with lowest levels in light drinkers (between 0.5 to 0.99 units per day) relative to the other drinking categories. However no significant association between alcohol intake and HOMA score was observed in fully adjusted analyses, including adjustment for dietary saturated fat and fruit and vegetables intake. In logistic regression analysis with insulin resistance (categorical) as the dependent variable, we observed that ex-drinkers were at higher risk of insulin resistance compared to occasional drinkers independently of age, sex, BMI and waist circumference, (OR=2.4, 95% CI, 1.1-5.7, p=0.04). On further adjustment for potential confounders including diet this association was also attenuated and was non-significant. CONCLUSIONS: The reported effects of alcohol intake on insulin resistance may be confounded by other aspects of lifestyle, especially diet.

Alcohol Drinking↗
PubMed2026

Evolution and domestication-trait associations of ultra-long centromere haplotypes in pepper plants.

Centromeric and pericentromeric regions of most eukaryotic genomes are highly repetitive and strongly recombination-suppressed, confounding efforts to resolve genetic variation, population structure and phenotypic associations. Pepper (Capsicum annuum) centromeres are nearly devoid of satellite repeats, facilitating assembly and population-level comparison of centromeric regions. Here we integrate 9 near-complete genome assemblies, CENH3 ChIP-seq profiles from 26 diverse accessions, and resequencing and phenotypic data from ~400 cultivated and wild accessions to investigate population-level diversity and phenotypic relevance of pepper peri/centromeric regions. Functional centromere positions are largely fixed on 8 of 12 chromosomes, whereas the remaining 4 carry distinct centromeric epialleles shaped mainly by centromere repositioning and pericentromeric inversions. Pepper centromeres are embedded within ultra-long centromere-spanning haplotype (cenhap) blocks, ranging from 29.8 to 112.9 Mb and collectively covering 23.96% of the genome; each block contains only 1-4 major haplotypes. Some cenhaps may act as supergene-like units and are strongly associated with fruit traits, probably because recombination-suppressed intervals harbour multiple fruit-related genes, including OFP and F-box genes. F2 segregation assays further reveal transmission distortion of chromosomes carrying alternative cenhaps. Together, these findings highlight peri/centromeric regions as underrecognized reservoirs of agronomically important variation.

Centromere↗
PubMed1992

Looking at proteins: representations, folding, packing, and design. Biophysical Society National Lecture, 1992.

Looking at proteins is an active process of interpretation and selection, emphasizing some features and deleting others. Multiple representations are needed, for such purposes as showing motions or conveying both the chain connectivity and the three-dimensional shape simultaneously. In studying and comparing protein structures, ideas are suggested about the determinants of tertiary structure and of folding (e.g., that Greek key beta barrels may fold up two strands at a time). The design and synthesis of new proteins "from scratch" provides a route toward the experimental testing of such ideas. It has also been a fruitful new perspective from which to look at structures, requiring such things as statistics on very narrowly defined structural categories and explicit attention to "negative design" criteria that actively block unwanted alternatives (e.g., reverse topology of a helix bundle, or edge-to-edge aggregation of beta sheets). Recently, the field of protein design has produced a rather unexpected general result: apparently we do indeed know enough to successfully design proteins that fold into approximately correct structures, but not enough to design unique, native-like structures. The degree of order varies considerably, but even the best designed material shows multiple conformations by NMR, more similar to a "molten globule" folding intermediate than to a well ordered native tertiary structure. In response to this conclusion, we are now working on systems that test useful questions with approximate structures (such as determining which factors most influence the choice of helix-bundle topology) and also analyzing how natural proteins achieve unique core conformations (e.g., for side chains on the interior side of a beta sheet, illustrated in the kinemages).

Amino Acid Sequence↗
PubMed2003

Division of labor between the hemispheres for complex but not simple tasks: an implemented connectionist model.

When stimuli have to be matched in a complex task (such as whether 2 letters have the same name), then performance is better when stimuli are presented across the hemispheres of the brain, whereas for simpler tasks (such as whether 2 letters have the same shape), better performance is achieved when stimuli are presented unilaterally. The authors show that this bilateral distribution advantage effect emerged spontaneously in a neural network model learning to solve simple and complex tasks with separate input layers and separate, but interconnected, resources in a hidden layer. The authors show that relating computational models to behavioral and imaging data proves fruitful for understanding hemispheric processing and generating testable hypotheses.

Brain↗
PubMed2006

Comparison of octopamine-like immunoreactivity in the brains of the fruit fly and blow fly.

A serum raised against conjugated octopamine reveals structurally comparable systems of perikarya and arborizations in protocerebral neuropils of two species of Diptera, Drosophila melanogaster and Phaenicia sericata; the latter is used extensively for electrophysiological studies of the optic lobes and their central projections. Clusters of cell bodies in the brain as well as midline perikarya provide octopamine-like immunoreactive processes to the optic lobes, circumscribed regions of the protocerebrum and the central complex, particularly the protocerebral bridge, fan-shaped body, and ellipsoid body. Ventral unpaired median somata provide immunoreactive processes within the subesophageal ganglion and tritocerebrum. Ascending neurites from these cells also supply the antennal lobe glomeruli, regions of the lateral protocerebrum, the mushroom body calyces, and the lobula complex. The mushroom body's gamma lobes contain immunoreactive processes that originate from processes that arborize in the protocerebrum. The present observations are discussed with respect to similarities and differences between two species of Diptera, one of which has neurons large enough for intracellular penetrations. The results are also discussed with respect to recent studies on octopamine-immunoreactive organization in honey bees and cockroaches and the suggested roles of octopamine in sensory processing, learning, and memory.

Animals↗
PubMed2003

Sir Nicholas Harold Ridley. He changed the world, so that we might better see it.

Cataract surgery with intraocular lens (IOL) implantation has become the most common and most successful of all operations in medicine. Sir Harold Ridley's first cataract extraction with implantation of an IOL marked the beginning of a major change in the practice of ophthalmology. Millions of patients worldwide have benefited from Sir Ridley's invention, and are likely to continue to derive benefit from this device. However, the development of the IOL was not without its share of ups and downs. Sir Harold Ridley, the inventor of IOL, died at the age of 94, on 25 May 2001, and ophthalmology lost one of its greatest and most influential practitioners. We are happy that he lived to enjoy the fruits of his labour--to see the amazing improvements and the expansive growth that evolved in the cataract-IOL technique, from early and unsatisfactory operations in previous decades, to the superb results attainable today. The invention of the IOL has not been just the addition of one new form of treatment, but rather, Sir Harold's tiny disc-shaped sliver of plastic has changed the world so that our patients may better see it. This article presents a brief biographical sketch of Sir Harold and lists his major inventions and contributions to ophthalmology.

Cataract Extraction↗
PubMed2004

Influence of the substrate on the ultrastructure of Pleurotus pulmonarius fruit body primordia.

Pleurotus pulmonarius fruit body primordia (FBP) formed on potato extract agar (PEA) and wheat straw-based media (WS) were studied. When grown on PEA, FBP hyphae had a large number of vacuoles and less stainable cytoplasmic material. In contrast, when grown on WS, there was abundant cytoplasmic material and fewer vacuoles. FBP grown on WS had a more well-defined mushroom shape than those grown on PEA. The average hyphal diameters on PEA and WS were 4.15 and 3.52 micro m, respectively; the average hyphal lengths were 11.75 and 11.80 micro m, respectively. The control mechanisms regulating formation of the normal shape and size of FBP might be more dependent on the amount of cytoplasmic material than on the physical volume of the hyphal compartment. Since the ultrastructure of the hyphal compartment, which makes up the substance of the FBP, depends on the substrate in which the FBP has been grown, the composition of the substrate may be important for manipulating the nutritive and organoleptic characteristics of the mushroom crop.

Hyphae↗
PubMed2003

Viability selection at three early life stages of the tropical tree, Platypodium elegans (Fabaceae, Papilionoideae).

Given the enormous number and high mortality of fertilized ovules in plants, it is possible that selection during the earliest stages of the life cycle plays an important role in shaping the genetic composition of plant populations. Previous research involving selection component analyses found strong evidence for viability selection in annual plant species. Yet despite this evidence, few attempts have been made to identify the magnitude and timing of viability selection as well as the mechanisms responsible for mortality among genotypes. Platypodium elegans, a Neotropical tree with high rates of early fruit mortality, represents an opportunity to study viability selection at a level of discernment not previously possible. Microsatellite markers were used to analyze the genetic composition of aborted embryos, as well as mature seeds and seedlings of the same cohort. While selection resulted in an overall decrease in self-fertilized progeny across each life stage, the greatest change in the genetic composition of progeny occurred between mature seeds and established seedlings. This suggested that inbreeding depression, and not late-acting self-incompatibility, was responsible for early selection. An investigation of the mature seed stage revealed that self-fertilized seeds weigh significantly less than outcrossed seeds. The result of this early selection conceals the mixed-mating system and high levels of inbreeding depression in Platypodium elegans, resulting in an apparently outcrossed adult population that does not differ significantly from Hardy-Weinberg expectations.

Alleles↗
PubMed1987

Fibre and the diabetic diet. An evaluation of the metabolic response to standardized meals.

Dietary fibre has a beneficial influence on glucose homeostasis, varying for different fibre sources. Fruit, wheat, rye and beet fibre were studied in isoenergetic meals for NIDD patients and healthy volunteers. The effects of extrusion cooking and flaking were also evaluated. The metabolic response was followed by continuous glucose monitoring and by analyses of pancreatic and gastrointestinal hormones as well as plasma lipid concentrations, For NIDD patients the effects, reflected in the area and the shape of the glucose curve, were greater for the more soluble fibre types, but the insulin and C-peptide responses were largely unaffected by dietary fibre. Beet fibre gave increased somatostatin concentrations also in age-matched healthy controls. They showed, however, unchanged plasma glucose responses and markedly decreased insulin and C-peptide levels. These changes were associated with less pronounced postprandial glycerol reduction, but otherwise none of the fibre preparations affected the postprandial lipemia. Extruded bread, based on wholegrain wheat flour, with high availability of in vitro starch, elicited a greater glucose response than wholegrain wheat bread, associated with a modest increase of GIP and insulin and with a stimulated early glucagon secretion. Flaked rye seemed to contain both faster and slower carbohydrates than the corresponding rye bread of similar fibre content. Analyses of the glucose curves suggested that the effect of fibre might be mediated by an effect on glucose absorption and parallel experiments in rat indicated that a delayed rate of gastric emptying might contribute. Further, the liver glycogen content was higher in rats given a slowly absorbed gastric load. A realistic increase in fibre content, given in long-term treatment, improved the metabolic control in NIDD patients, by decreasing the fasting blood glucose and LDL-cholesterol levels, as well as the LDL/HDL ratio. Hypothetically, slower absorption achieved with dietary fibre increases the proportion of glycogen in the liver. This postprandial improvement may cause the long-term trend to normalization of the fasting blood glucose level.

Aged↗
PubMedDate not supplied

[Congenital toxoplasmosis].

INTRODUCTION: Toxoplasma gondii is a ubiquitous parasite of all species of mammals and birds (1). Most often the infection in the immunocompetent persons is asymptomatic. Symptoms (if present) are usually mild and self-limited. Infection in the fetus and immunodeficient patients may lead up to clinically severe and often fatal toxoplasmosis (2). ETIOLOGY: Toxoplasma exists in three forms: oocysts, tissue cysts and tachyzoites. The definitive hosts of Toxoplasma are members of the cat family. They shed unsporulated oocysts in the feces. After sporulation oocysts become infectious. Tachyzoites are crescent-shaped forms responsible for manifestations of acute Toxoplasma infection in the intermediate hosts (6,7). Cysts are formed, particularly in brain, heart muscle and skeletal muscles. The cyst forms of the parasite are seen in the latent stage of the infection. Postnatally acquired toxoplasmosis is a consequence of infection from cysts (by ingestion of undercooked meat of infected animals), oocysts (by ingestion of soil, fruits, vegetables contaminated by cat feces) and tachyzoites (by blood transfusion). Congenital Toxoplasma infection causes congenital toxoplasmosis. PATHOGENESIS: Some authors represented the concept that latent (chronic) infection with Toxoplasma during pregnancy can result in congenital infection in the offspring (8-11). Now it is generally agreed that congenital transmission of Toxoplasma occurs only when the infection is acquired during gestation (6,7, 12-16). More than half of the fetuses escape infection, one-third are definitely infected, and the infection is more often subclinical than clinically obvious (15). The fetus is infected hematogenously from inflammatory foci in the placenta formed during parasitemia in the mother. CLINICAL MANIFESTATIONS: Approximately 75% of congenitally infected newborns are asymptomatic. Wilson's study indicates that nearly all such children will develop adverse sequelae (neurologic, intellectual, audiologic and ophthalmologic) 21). Severe forms of congenital toxoplasmosis occur only in 10% of infected offsprings. Clinical manifestations of congenital toxoplasmosis are different. Clinical findings in patients with congenital toxoplasmosis may include: chorioretinitis and other ocular findings, central nervous system abnormalities (such as microcephaly, hydrocephalus, encephalomyelitis, seizures and mental retardation), icterus, hepatosplenomegaly, rash, anemia, erythroblastosis, thrombopenia. INCIDENCE: Incidence of human congenital toxoplasmosis is different in different countries. The incidence in Britain is 0.6 subclinical infection and 0.09 severe illnesses per 1000 births (22). The incidence in USA is between 1/1000 and 1/8000 live births (23). In France the incidence is 1/2000. In Slovenia the incidence is 2.3 cases per 1000 births (25). DIAGNOSIS: Diagnostic methods are: 1. Isolation of the parasite from the placenta, blood, body fluids (by inoculation of specimens into mice or tissue cultures). 2. Histologically by demonstration of tachyzoites in tissue sections or smears of body fluids. 3. Serologic diagnosis. The most important diagnostic methods are serologic tests. For diagnosis of congenital toxoplasmosis determination of IgM antibody (in the serum of newborn infant) has the greatest importance. The fetus is able to produce IgM specific antibody. The presence of IgM antibodies in serum obtained from the neonate is an evidence of fetus infection in utero. Maternal IgM antibodies do not pass the placenta. IgM antibodies may be demonstrable by indirect fluorescent antibody test (IgM-IFA), enzyme linked immunosorbent assay (IgM-ELISA), double sendwich IgM enzyme-linked immunosorbent assay (DS-IgM-ELISA), IgM immunosorbent agglutination assay (IgM-ISAGA) and reversed enzyme immunoassay (REI). For diagnosis of congenital toxoplasmosis the next tests are also applied: Sabin-Feldman Dye test, indirect fluorescent antibody test for IgG antibodies (IgG-IFA) and enzyme

Female↗