Surgical outcomes of complicated cataract with pediatric trematode granulomatous uveitis

AIM: To describe the clinical characteristics and surgical outcomes of complicated cataract with pediatric trematodal granulomatous uveitis (TGU).METHODS: Patients of cataract with TGU in the membranous (inactive) stage underwent cataract surgery with intraocular lens (IOL) implantation. Preoperative history and ophthalmic examination were conducted for all cases, whereas Schimphlug imaging and corneal topography were done for some patients. Postoperative follow up was done on the 1st, 2nd, and 5th postoperative days after surgery. Then, it was done at least at one, three, and six months postoperatively. Intraoperative and postoperative complications and the methods of their management were reported.RESULTS: Twelve eyes of 12 male children were included in this study ranging from 8 to 16y. The mean best corrected Snellen visual acuity (BCVA) was significantly improved from 0.09±0.06 preoperatively to 0.37±0.11 at the final visit 6mo postoperatively (P<0.001). Schimphlug imaging and corneal topography showed flattening of the anterior surface of the inferior cornea. Intraoperative difficulties and complications included the poor dilatability of the drown down pupil, strong posterior synechia between the anterior lens capsule and the iris at the site of the inferior retrocorneal vascularized membrane and hyphema. All cases underwent primary hydrophobic IOL implantation.CONCLUSION: Surgery for this type of cataract is relatively safe and effective. It is associated with some specific difficulties and complications that should be considered during surgery and follow up.     

Cranial lesions caused by helminth parasites and morphological traits in the European polecat Mustela putorius

Summary  We investigated the occurrence of cranial lesions caused by helminth parasites in the European polecat Mustela putorius in a museum collection in Slovakia. Selected traits of polecat body morphology and condition were studied with respect to the prevalence of the parasites, and number and extent of helminth-caused lesions in crania of 183 adult polecats. The trematode Troglotrema acutum was identified as the parasitic agent (prevalence 62.6 %), with a strong relationship between number of lesions and extent of cranial damage (surface of cranium). Prevalence of infection did not differ significantly between sexes (68.9 % in females, 51.1 % in males). Females with lesions by Troglotrema acutum have significantly greater braincase breadth than uninfected ones. Among males, infected individuals were generally significantly heavier and larger than uninfected individuals. Therefore, contrary to assumptions, it seems that parasites did not influence significantly body measurements of the animals, and differences are probably rather a result of an intra-sample age variation among infected polecats (older individuals are bigger, more probably infected and damage is more pronounced).     

Frog decline,frog malformations,and a comparison of frog and human health

The decline in frog populations and the increase in the frequency of frog malformations are discussed. Topics considered for analysis include chytridiomycosis, retinoids, UV‐B radiation, chemical contaminants, environmental threats, introduced invasive species and predation, unsustainable use, and enigmatic decline. Care must be taken to distinguish between hypotheses, laboratory experiments, and the findings in feral frog populations. Clearly, the causes of population decline and malformations are heterogeneous. The subject of frogs and humans is addressed under three subheadings: the importance of frogs to human societies, medical implications of frog studies, and a comparison of frog and human disease factors. © 2001 Wiley‐Liss, Inc.     

Distribution of freshwater snails in family-based VAC ponds and associated waterbodies with special reference to intermediate hosts of fish-borne zoonotic trematodes in Nam Dinh Province, Vietnam

Fish-borne zoonotic trematodes, such as Clonorchis sinensis, heterophyids and others, constitute a public health concern in parts of northern Vietnam and infections with these trematodes are often thought to be linked to fish culture. One common fish culture system is the integrated fish-livestock (VAC) ponds where individual households have 1 or more ponds. Fish fry, mainly of various carp species, produced in hatcheries, not necessarily local, are introduced into nursery ponds and after approximately 6 weeks, juvenile fishes are transferred to household ponds, referred to as grow-out ponds. Grow-out ponds are usually fertilized with organic debris, including animal excreta, to stimulate algal growth and subsequently fish growth. This paper describes the distribution of freshwater snails and occurrence of trematode infections in these in VAC ponds and associated habitats as part of a major study on risk factors of FZT infections in cultured fish in two communes, Nghia Lac and Nghia Phu, Nghia Hung District, Nam Dinh Province. The area is under intense rice cultivation with an extensive canal network supplying fields and also household VAC ponds. A total of 16 snail species was found and four were widely distributed i.e. Angulyagra polyzonata, Melanoides tuberculata, Bithynia fuchsiana and Pomacea insularum. Snail diversity and counts were higher in nursery ponds than in grow-out ponds. Species of the families Thiaridae and Viviparidae were more abundant than other species in VAC ponds while species of the Bithyniidae, Stenothyridae and Planorbidae dominated in rice fields and small canals. Trematode infections were found in eight snail species and among these M. tuberculata had the highest overall prevalence of infection (13.28%). No trematode infections were found in species of the Viviparidae and Ampullaridae except for metacercariae. Parapleurolophocercous and pleurolophocercous cercariae constituted the most common type of cercariae recovered, contributing 40.6% of all infections followed by echinostome cercariae (35.0%) and xiphidiocercariae (17.3%). Bithynia fuschiana and M. tuberculata had the most diverse trematode fauna. C. sinensis was not recorded in this study. The VAC pond system in this area, is very important for transmission of minute intestinal trematodes while they play little role in transmission of C. sinensis as its intermediate hosts, bithynid snails, rarely occur in these ponds. From a public health perspective this is positive as the effects of infections with intestinal trematodes are considered mild. On the other hand it is possible that even such subtle effects could have importance in public health as transmission is very intense in the area. And this in combination with the aquaculture importance, reduced marketability of fishes with high metacercariae loads, warrants that control efforts against these trematodes are initiated to reduce transmission in this production system.     

Hormonal and immunological mechanisms mediating sex differences in parasite infection

The prevalence and intensity of infections caused by protozoa, nematodes, trematodes, cestodes, and arthropods is higher in males than females. The primary thesis of this review is that immunological differences exist between the sexes that may underlie increased parasitism in males compared to females. Several field and laboratory studies link sex differences in immune function with circulating steroid hormones; thus, the roles of sex steroids, including testosterone, oestradiol, and progesterone, as well as glucocorticoids will be discussed. Not only can host hormones affect responses to infection, but parasites can both produce and alter hormone concentrations in their hosts. The extent to which changes in endocrine-immune interactions following infection are mediated by the host or the parasite will be considered. Although males are more susceptible than females to many parasites, there are parasites for which males are more resistant than females and endocrine-immune interactions may underlie this sex reversal. Finally, although immunological differences exist between the sexes, genetic and behavioural differences may explain some variability in response to infection and will be explored as alternative hypotheses for how differences between the sexes contribute to dimorphic responses to parasites.     

Localization of tyrosine hydroxylase‐like immunoreactivity in the nervous systems of Biomphalaria glabrata and Biomphalaria alexandrina,intermediate hosts for schistosomiasis

Planorbid snails of the genus Biomphalaria are major intermediate hosts for the digenetic trematode parasite Schistosoma mansoni. Evidence suggests that levels of the neurotransmitter dopamine (DA) are reduced during the course of S. mansoni multiplication and transformation within the snail. This investigation used immunohistochemical methods to localize tyrosine hydroxylase (TH), the rate‐limiting enzyme in the biosynthesis of catecholamines, in the nervous system of Biomphalaria. The two species examined, Biomphalaria glabrata and Biomphalaria alexandrina, are the major intermediate hosts for S. mansoni in sub‐Saharan Africa, where more than 90% of global cases of human intestinal schistosomiasis occur. TH‐like immunoreactive (THli) neurons were distributed throughout the central nervous system (CNS) and labeled fibers were present in all commissures, connectives, and nerves. Some asymmetries were observed, including a large distinctive neuron (LPeD1) in the pedal ganglion described previously in several pulmonates. The majority of TH‐like immunoreactive neurons were detected in the peripheral nervous system (PNS), especially in lip and foot regions of the anterior integument. Independent observations supporting the dopaminergic phenotype of THli neurons included 1) block of LPeD1 synaptic signaling by the D2/3 antagonist sulpiride, and 2) the similar localization of aqueous aldehyde (FaGlu)‐induced fluorescence. The distribution of THli neurons indicates that, as in other gastropods, dopamine functions as a sensory neurotransmitter and in the regulation of feeding and reproductive behaviors in Biomphalaria. It is hypothesized that infection could stimulate transmitter release from dopaminergic sensory neurons and that dopaminergic signaling could contribute to modifications of both host and parasite behavior. J. Comp. Neurol. 522:2532–2552, 2014. © 2014 Wiley Periodicals, Inc.     

湖北省恩施县肺吸虫病及病原调查初报

本文报告恩施县肺吸虫病和肺吸虫病原的初步调查结果。总共检查19,206人,皮试阳性者2740人,阳性检出率14.27％。对其中城关等八个公社13389人的检查结果进行了分析、讨论。报告了肺吸虫的三种螃蟹宿主;详细捕述了当地肺吸虫囊蚴、脱囊后尾蚴、虫卵及成虫各期的形态,并进行了测量、比较和讨论,其结果均接近陈心陶的报告。证实了该地肺吸虫病原以斯氏狸殖吸虫为主。     

广东家禽前殖属吸虫调查及一新种述描

作者从1984～1987年,进行广东省畜禽寄生虫区系调查时,发现家禽前殖吸虫11种。其中东方前殖吸虫Prosthogonimus orientalis、中华前殖吸虫P.sinensis、霍鲁前殖吸虫P.horiuchii三种为省内新记录;印度前殖吸虫P.indicus为国内新记录;广州前殖吸虫新种P.cantonensis sp。广州前殖吸虫新种主要特征为:角皮呈鳞片状突出并具有小刺;子宫高度盘卷但不充满体缘;卵黄腺前界始于卵巢前缘水平线,后界止于睾丸后方远;两肠支伸达体后端。     

PCR-RAPD技术在医学蠕虫研究中的应用进展

PCR-RAPD技术是建立在PCR基础上的一种随机引物扩增技术,已广泛应用于种系鉴定、遗传分析、连锁图的构建、疾病诊断和基因分离等众多领域。近年来该技术在寄生虫研究中应用较广,本文介绍了国内外有关吸虫、绦虫和线虫等蠕虫方面的应用报道。