Echinococcosis in sub-Saharan Africa: emerging complexity.

Cystic echinococcosis occurs in most regions of sub-Saharan Africa, but the frequency of this zoonosis differs considerably among and within countries. Especially human cases seem to be focally distributed. A number of environmental and behavioural factors partially explain this pattern, i.e. density of livestock, presence of dogs, uncontrolled slaughter, and hygiene. In addition, the various taxa of Echinococcus spp. are known to differ considerably in infectivity to different host species including humans. Genetic characterizations of isolates, which are necessary to evaluate the impact of this factor - so far done in only a few countries - indicate that the diversity of Echinococcus spp. in Sub-Saharan Africa is greater than on any other continent. The very incomplete data which are available show that sympatrical taxa may infect different hosts, others may be geographically restricted, some life cycles involve livestock, others wild animals. Possible implications of this complexity for public health, livestock economy and conservation are briefly discussed.

Echinococcus species in African wildlife.

Cystic echinococcosis, caused by different species of the Echinococcus granulosus complex, is an important zoonotic disease with a particular impact on pastoralist societies. In addition to the widespread taxa with synanthropic transmission, a number of Echinococcus species were described from African wild carnivores early in the 20th century. For lack of study material, most of these were later tentatively synonymized with E. granulosus. Early infection experiments with wildlife isolates gave ambiguous results due to the use of unspecified parasite material, and only recently molecular methods provided the opportunity to shed light on the confusing scenery e.g. by characterizing E. felidis from the African lion. Here we will summarize the convoluted history of Echinococcus research in sub-Saharan Africa and highlight the necessity of molecular surveys to establish the life cycles and estimate the zoonotic potential of these parasites.

Cystic echinococcosis in Turkey: genetic variability and first record of the pig strain (G7) in the country.

A sample of 22 Echinococcus granulosus isolates collected from 12 sheep and ten humans from a focus of cystic echinococcosis in western Turkey was examined by DNA sequencing of four mitochondrial genes (cox1, atp6, nad1, rrnS). Results demonstrated the presence of two species of E. granulosus complex, E. granulosus sensu stricto and E. canadensis. Of E. granulosus sensu stricto, the G1 genotype (including three microvariants) was found in 17 isolates from humans and sheep, the G3 genotype and an intermediate form G1/G3 in one isolate each (both from sheep). Of E. canadensis, the pig strain G7 was found in three isolates from sheep and human. This is the first report of this strain in Turkey. Its presence has implications for local control programs due to its shorter maturation rate in dogs compared with E. granulosus sensu stricto. Goat and/or wild boar are likely reservoirs for G7 in the region. We provided further data on the pattern and frequency of nucleotide substitutions within the G1/G3 cluster. Based on our results and GenBank records, G2 (Tasmanian sheep strain) is not considered as a discrete genotypic unit, as its sequences at polymorphic sites conform to microvariants of both G1 and (more often) G3.

Surface composition analysis of failed cementless CoCr- and Ti-base-alloy total hip implants.

The surfaces of retrieved failed cementless total hip implants made of cobalt-chromium-molybdenum casting alloy and of wrought titanium 6-aluminum 4-vanadium alloy were studied with the use of scanning-electron microscopy (SEM), energy-dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS). New implants of the same make served as controls. The XPS scans revealed a dense carbon layer on the entire analyzed specimen. The relative composition of the titanium alloy implants showed an overall agreement with the international standards for implants for surgery, and the overall surface composition did not change over the period of the implantation. However, an inhomogeneous distribution of the constituents could be demonstrated in the retrieved as well as in the new MEC-screw rings made of TiAl6V4 alloy, an implant that has been linked to a high early failure rate. In the CoCr-alloy components (Lord-screw rings) a high percentage of aluminum, mainly organized in aluminum inclusions, was found in the retrieved as well as in the new implants.

[CT-guided sympathicolysis in peripheral artery disease - Indications, patient selection and long-term results]. / CT-gesteuerte Sympathikolyse bei peripherer arterieller Verschlusskrankheit - Indikationen, Patientenauswahl, Langzeitergebnisse.

PURPOSE: Assessment of long-term results of CT-guided lumbar sympathicolysis (LSL) in advanced peripheral arterial vascular disease (pavd). Establishment of a suitable patient selection. PATIENTS AND METHODS: LSL was performed in 138 cases with Fontaine stages III (13 %) and IV (87 %). 250 consecutive patients were examined with a radionuclide perfusion study of the feet prior to and during peridural anaesthesia (PDA) in order to select suitable patients for LSL. LSL was not performed in patients with impaired perfusion under PDA (n = 112). Early and long-term results after one to five years were evaluated. RESULTS: In 79 % an initial improvement was found after LSL. After more than one year success was established in 38 %. 49 % of the cases had a progression of the disease. This is significantly better compared to a control group with conservative treatment and an initial improvement of 36 %. After more than one year only12 % revealed an improvement. In 82 % the disease was progressive. Diabetics showed also a positive response to LSL. CONCLUSION: LSL has a positive influence on the course of pvad in patients selected by radionuclide perfusion studies. Diabetes and angiographic findings do not play any first role in patient selection for LSL.