The Pattern of Defects in Mesorectal Specimens: Is There a Difference between Transanal and Laparoscopic Approaches?

BACKGROUND:: Total mesorectal excision has evolved from open to minimally invasive techniques. To overcome difficulties in the lowest part of the pelvis, transanal total mesorectal excision was introduced and has gained acceptance in the recent years. The results of transanal total mesorectal excision seem to be comparable to laparoscopic total mesorectal excision. Whether or not transanal total mesorectal excision has changed the pattern of defects in the retrieved mesorectal specimens is yet to be clarified. PURPOSE:: To determine the pattern of mesorectal defects following transanal total mesorectal excision, compared to laparoscopic total mesorectal excision. The primary end-point was the location of defects in the part of the mesorectum below the peritoneal reflection, as it is this part, which is dissected from below in the transanal total mesorectal excision procedure. METHODS:: From our transanal total mesorectal excision database that includes all transanal total mesorectal excision procedures performed at our institution since 2013, we have included 29 patients who originally had defects in their retrieved specimens. Another 29 patients who underwent laparoscopic total mesorectal excision with mesorectal defects served as a control group. All specimen photos and pathology reports were reviewed systematically; sites and pattern of defects were defined. RESULTS:: A higher ratio of the defects in the laparoscopic total mesorectal excision group was located below the peritoneal reflection (P = 0.043). The distribution of defects by anatomical quadrant was not statistically different between the groups. CONCLUSIONS:: The ratio of defects below the peritoneal reflection was lower in the transanal total mesorectal excision group. Whether this is due to a lower incidence of defect in transanal total mesorectal excision is not part of our study.

Standardised survey method for identifying catchment risks to water quality.

This paper describes the development and application of a systematic methodology to identify and quantify risks in drinking water and recreational catchments. The methodology assesses microbial and chemical contaminants from both diffuse and point sources within a catchment using Escherichia coli, protozoan pathogens and chemicals (including fuel and pesticides) as index contaminants. Hazard source information is gathered by a defined sanitary survey process involving use of a software tool which groups hazards into six types: sewage infrastructure, on-site sewage systems, industrial, stormwater, agriculture and recreational sites. The survey estimates the likelihood of the site affecting catchment water quality, and the potential consequences, enabling the calculation of risk for individual sites. These risks are integrated to calculate a cumulative risk for each sub-catchment and the whole catchment. The cumulative risks process accounts for the proportion of potential input sources surveyed and for transfer of contaminants from upstream to downstream sub-catchments. The output risk matrices show the relative risk sources for each of the index contaminants, highlighting those with the greatest impact on water quality at a sub-catchment and catchment level. Verification of the sanitary survey assessments and prioritisation is achieved by comparison with water quality data and microbial source tracking.

Genotypes of Cryptosporidium from Sydney water catchment areas.

AIMS: Currently cryptosporidiosis represents the major public health concern of water utilities in developed nations and increasingly, new species and genotypes of Cryptosporidium are being identified in which the infectivity for humans is not clear. The complicated epidemiology of Cryptosporidium and the fact that the majority of species and genotypes of Cryptosporidium cannot be distinguished morphologically makes the assessment of public health risk difficult if oocysts are detected in the raw water supplies. The aim of this study was to use molecular tools to identify sources of Cryptosporidium from the Warragamba catchment area of Sydney, Australia. METHODS AND RESULTS: Both faecal and water samples from the catchment area were collected and screened using immunomagnetic separation (IMS) and immunofluorescence microscopy. Samples that contained Cryptosporidium oocysts were genotyped using sequence and phylogenetic analysis of the 18S rDNA, and the heat-shock (HSP-70) gene. Analysis identified five Cryptosporidium species/genotypes including C. parvum (cattle genotype), C. suis, pig genotype II, the cervid genotype and a novel goat genotype. CONCLUSIONS: Monitoring and characterization of the sources of oocyst contamination in watersheds will aid in the development and implementation of the most appropriate watershed management policies to protect the public from the risks of waterborne Cryptosporidium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has shown that quantification by IMS analysis can be combined with the specificity of genotyping to provide an extremely valuable tool for assessing the human health risks from land use activities in drinking water catchments.

Evaluation of an internal positive control for Cryptosporidium and Giardia testing in water samples.

AIMS: An internal positive control for Cryptosporidium and Giardia monitoring was evaluated for use in routine water monitoring quality control. The control, known as ColorSeed C&G (BTF Pty Ltd, Sydney, Australia), is a suspension containing exactly 100 Cryptosporidium oocysts and 100 Giardia cysts that have been modified by attachment of Texas Red to the cell wall, allowing them to be differentiated from unmodified oocysts and cysts. The control enables recovery efficiencies to be determined for every water sample analysed. METHODS AND RESULTS: A total of 494 water samples were seeded with ColorSeed C&G and with unlabelled Cryptosporidium and Giardia and then analysed. Additionally, the robustness of the ColorSeed labelling was challenged with various chemical treatments. Recoveries were significantly lower for the ColorSeed Texas Red labelled Cryptosporidium and Giardia than recoveries of unlabelled Cryptosporidium and Giardia. However, the differences in recoveries were small. On average ColorSeed Cryptosporidium recoveries were 3.3% lower than unlabelled Cryptosporidium, and ColorSeed Giardia recoveries were 4% lower than unlabelled Giardia. CONCLUSIONS: ColorSeed C&G is suitable for use as an internal positive control for routine monitoring of both treated and raw water samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The small differences in recoveries are unlikely to limit the usefulness of ColorSeed C&G as an internal positive control. The ColorSeed labelling was found to be robust after different treatments.

Design and testing of a 6-component ballistocardiographic bed.

Ballistocardiography is a non-invasive technique for the assessment of the cardiac function. It consists in studying the resultant forces generated by the blood mass flowing in the cardio-circulatory system while the subject lies on an instrumented bed. In the past, ballistocardiography was in large part limited by the signal processing and data acquisition capabilities. Technology improvements have countered these limitations. Previous studies by the authors using a regular size force plate have shown the capability of detecting cardiac activity in the human body. However, many patients with severe disorders cannot stand on a force plate for the duration required to acquire adequate data. Thus, a force plate, which performs as a ballistocardiographic bed, would allow patients to lie down in a stable position while body tremor data are acquired. To evaluate this idea, a highly sensitive ballistocardiographic bed was built using strain gage technology. Then, using high-resolution data acquisition software, the sensitivity of the instrument and the capability to obtain ballistocardiographic data were tested. Future developments include the analysis of ballistocardiographic data obtained from the bed to search their possible relation with cardio-circulatory and neurologic pathologies.

[The significance of nephrosonography for the early recognition of kidney tumors]. / Die Bedeutung der Nephrosonographie zur Früherkennung von Nierentumoren.

In the following presentation the criteria of solid kidney tumours and their differential diagnosis are demonstrated. 175 patients operated upon since 1976 demonstrate the significance of ultrasonography for early detection of kidney tumours. The results show that early detection of kidney tumours is possible by nephrosonography; an early and simple operation can be performed and improves prognosis dramatically.

Development of Theileria mutans (Theiler, 1906) in the gut and the haemolymph of the tick Amblyomma variegatum (Fabricius, 1794).

The development of Theileria mutans in the gut and haemolymph of its tick vector, Amblyomma variegatum, was studied by Giemsa-stained smears after the nymphal tick had completed engorgement on parasitaemic calves. Sexual stages occurred in the gut between five and seven days after repletion. The zygotes were observed in the gut from day 29 and the kinetes from day 30, i.e. three and four days after the nymphs moulted to adults. From day 34 kinetes were observed in the haemolymph. The developmental stages of T. mutans in the tick were compared with those of other Theileria spp. of cattle.

On the life cycle of Theileria velifera (Uilenberg, 1964) in the gut and the haemolymph of the tick vector Amblyomma variegatum (Fabriciu, 1794).

The development of Theileria velifera in the gut and the haemolymph of the tick vector Amblyomma variegatum is described. Between days three and eight after repletion various sexual stages are present in the gut of the nymphs. Zygotes were detected in the gut on day 14, while undifferentiated kinetes first appeared on day 15. In the haemolymph, differentiated kinetes were observed from day 16 after repletion onwards. Zygotes and kinetes were also found after the moult, in the adult tick, for a prolonged period of time. The results of this study show that the developmental stages of T. velifera in the gut and haemolymph are characteristic of the genus Theileria.

Electron-microscopic studies on Theileria ovis Rodhain, 1916: development of kinetics in the gut of the vector tick, Rhipicephalus evertsi evertsi Neumann, 1897, and their transformation within cells of the salivary glands.

Gamogony of Theileria ovis Rodhain occurs within the gut of nymphs of the tick Rhipicephalus evertsi evertsi Neumann. After molting, spherical and ovoid parasites are found within the intestinal cells of the ticks. These stages are thought to be zygotes, because they undergo a transformation process leading ultimately (in 3 days) to the formation of a motile stage, the kinete, the fine structure of which is very similar to that of the ookinetes of the hemosporidia. The kinete leaves the gut cells of the tick and penetrates the salivary gland cells where it produces infective stages (the sporozoites). These stages may be transmitted to sheep during the next blood meal of the tick. The developmental processes of T. ovis are compared to those of Hemosporina.

Electron microscopic studies on the development of kinetes of Theileria parva Theiler, 1904 in the gut of the vector ticks Rhipicephalus appendiculatus Neumann, 1901.

The development of motile stages, called kinetes, from a stationary stage (regarded as zygote) has been followed in Theileria parva by means of electron miscroscopy. This process started after moult of the tick nymphs which had sucked on highly infected calves, i.e. about 20 days after repletion (a.r.) of the ticks. The transformation took place by formation of a growing protrusion (= anlage) into an inner, enlarging vacuole. During this process the limiting membrane of the enlarging vacuole serves as the outer membrane of the developing motile stage, whereas the two inner ones as well as the subpellicular microtubules are newly formed. This transformation proceeds rapidly, so that on the 25th day a.r. most of the kinetes have already left the gut cells and started penetration into the salivary gland cells. On the way to the salivary glands nuclear divisions occurred within the kinetes. The steps of the transformation described were compared to those in T. annulata and to ookinete formation in haemosporidia.