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A Mathis

Publications and source records attributed to A Mathis.

At least 19 recordsLinked to original sources
PubMed2007

Genotyping of Babesia bigemina from cattle from a non-endemic area (Switzerland).

In August 2002, bovine anaplasmosis and concurrent infections with Mycoplasma sp. and piroplasms were reported in a cattle herd in an alpine region of Switzerland. The piroplasms were identified by PCR/sequencing of part of the 18S rRNA gene as Babesia bigemina and Theileria of the buffeli/sergenti/orientalis-complex, which have never been diagnosed in Switzerland before. The B. bigemina isolate was genetically characterised at two loci and compared with isolates from Italy, Spain, Turkey, Kenya and Mexico. Analysis of the internal transcribed spacer 2 (ITS2) of the rRNA genes revealed high polymorphism not only among the isolates but even within the isolates, and the presence of two types of the ITS2 in every isolate was confirmed. A dendrogram based on ITS2 sequences showed that the Swiss isolate was most closely related to a Spanish isolate but no sequences of the isolate from Switzerland were identical to any of the other isolates. The isolate from Italy was not positioned in the same cluster as the Swiss and the Spanish isolate. This had been anticipated as the nearest known endemic area of B. bigemina in Central Italy. Sequence analysis of the rhoptry-associated protein-1c gene (rap1c) confirmed the similarity of the Swiss and Spanish isolate. Hence, our molecular analyses of the Swiss B. bigemina isolate did not unequivocally track its geographical origin and the way of introduction remains obscure.

Animals↗
PubMed2006

[Surgical treatment of inferior retinal detachment: advantages of postoperative traction of the right inferior muscle].

AIM: To evaluate the advantages of keeping the right inferior muscle in traction during external surgery for inferior retinal detachment. PATIENTS AND METHODS: This was a prospective study involving ten patients consecutively operated on for rhegmatogenous retinal detachment at the Toulouse-Rangueil Teaching Hospital. Internal plugging by air or a C2F6-air mixture was systematically performed, together with external indentation and total subretinal fluid puncture. At the end of surgery, a 2.0 silk thread was set beneath the right inferior muscle and kept in traction from the forehead for a few days. The patient was maintained feet up, in a dorsal decubitus posture. RESULTS: Results proved excellent, with ten anatomical successes. However, one patient had to have gas reinjected and in another subretinal fluid persisted for 3 months. DISCUSSION: The risk of surgical failure in inferior retinal detachment is greater because dabbing is more difficult to perform. To make this dabbing easier, we propose maintaining the ocular globe rearward by maintaining traction on the right inferior muscle, which produced excellent results. CONCLUSION: The technique proposed is easy to perform, and combined with internal dabbing and adequate patient positioning, it should help improve the surgical outcome of inferior retinal detachments.

Aged↗
PubMed2006

[How to perform intravitreal injections].

Drugs to treat retinal diseases are often injected intravitreally. This procedure can cause severe complications. We present ways to minimize the risk for complications. Rigorous preoperative antisepsis with povidone iodine, a sterile environment (using gloves and a mask for the injector, a lid speculum, and a drape on the eye to be injected), and immediate follow-up after injection are key issues of the injection technique.

Humans↗
PubMed2006

[Management of complicated retinal detachment using a heavy silicon oil as temporary tamponade].

PURPOSE: To assess the efficacy and safety of a heavy silicon oil (a silicon oil-RMN3 mixture, a mixed fluorinated and hydrocarbonated olefin) as temporary internal tamponade in selected cases of retinal detachment with inferior breaks. PATIENTS AND METHODS: Forty-six patients were operated on (inferior and/or posterior breaks: 38; proliferative vitreoretinopathy > or =C2: 18; anterior proliferative vitreoretinopathy: 14), with a mean follow-up of 39 months. Seventeen patients were operated on with a heavy silicon oil of a 1.03 g/cm3 density and 29 patients with a silicon oil of a 1.02 g/cm3 density. Heavy silicon oil was removed in 41 patients after a mean of 9.3 weeks. RESULTS: Anatomic success was achieved in 35 cases after a mean follow-up of 39 months. Recurrent retinal detachment with proliferative vitreoretinopathy occurred in eight cases during heavy silicon oil tamponade. The removal was difficult in three cases with the 1.02 g/cm3 density silicon oil. Complications included glaucoma (eight eyes), major emulsification (two eyes), and an intraocular inflammation reaction to topical steroids (five eyes). CONCLUSION: Heavy silicon oil (Oxane Hd) is as safe and effective as standard silicon oil in the treatment of selected retinal detachment, but intraocular manipulations are quite difficult. A prospective study is necessary to compare the efficacy of Oxane Hd and standard silicon oil in selected cases of retinal detachment with inferior breaks and in cases of large inferior retinectomy.

Adolescent↗
PubMed2006

[Specifications of retinal detachment surgery in highly myopic eyes of 10 or more dioptres and hemorrhagic complications: 79 cases].

INTRODUCTION: We report a series of 79 eyes undergoing primary surgery for rhegmatogenous retinal detachment associated with severe myopia greater than 10 diopters. Specific surgical procedures are recommended for these patients in order to minimize the high incidence of postoperative hemorrhagic complications. MATERIALS AND METHODS: Seventy-nine eyes of 76 patients treated for retinal detachment with severe myopia greater than 10 diopters were reviewed. Scleral buckling was performed in 21 eyes and pars plana vitrectomy in 58 eyes. RESULTS: After a mean follow-up period of 23.8 months, the final anatomical success rate was 93.7% (74 cases). Postoperative hemorrhagic complications (suprachoroidal hemorrhage and vitreous hemorrhage) occurred in four cases after scleral buckling and in ten cases after vitrectomy. DISCUSSION: In this study, primary scleral buckling for retinal detachment was less frequently performed than vitrectomy. Broad scleral buckling may not be associated with higher postoperative hemorrhagic complications, when the buckle does not extend over six clock hours. Postoperative hemorrhagic complications also occurred after vitrectomy; however, scleral buckling associated with vitrectomy does not seem to increase the complication rate. CONCLUSION: This retrospective study of 79 cases of rhegmatogenous retinal detachment with severe myopia higher than 10 diopters suggests that vitrectomy is often considered a primary procedure. Broad scleral buckling associated with vitrectomy is a safe and effective procedure, with an acceptable incidence of complications when not extending over six clock hours.

Choroid Hemorrhage↗
PubMed2006

[Piroplasms of ruminants in Switzerland and zoonotic significance of Babesia].

Piroplasms are tick-transmitted blood parasites belonging to the genera Babesia and Theileria. In western and southern Switzerland, B. divergens, a small Babesia species, has been known for a long time as a parasite of cattle. Recent investigations have revealed the autochthonous occurrence of this parasite also in central and eastern Switzerland. On the occasion of an outbreak of anaplasmosis in the canton of Grisons, however, B. bigemina, a large Babesia species, and Theileria of the buffeli/sergenti/orientalis species complex were for the first time identified; the epidemiology of these two piroplasms in Switzerland remains unknown until now. The recent identification by genetic analyses of B. divergens in wild ruminants contradicts the hitherto postulated strict host specificity of this Babesia species for cattle. B. divergens as well as the closely related Babesia spp. genotype EU1 have in single cases also been identified in splenectomized humans. The rodent babesia B. microti which causes a human infection that is considered an "emerging tick-borne disease" in the U.S.A., is widespread in rodent populations in Switzerland, but seems to be of minor relevance as zoonotic pathogen here. Reasons for this could be differences in virulence of the parasites or in the transmission by the respective tick-vectors on the two continents.

Animals↗
PubMed2005

[Retinal detachment by inferior tear: a poor prognosis?].

AIM: To determine whether a lower location of retinal wounds is a factor for poor prognosis in retinal detachment. PATIENTS AND METHOD: This retrospective study involved 248 medical records of patients who were operated on for retinal detachment in 2001 at the Toulouse-Rangueil Hospital Ophthalmology Department. We excluded retinal detachment of very short-sighted patients, diabetic patients and detachment secondary to trauma or relapses. We compared the incidence of surgical failure according to various parameters: condition of the crystalline lens, operative technique, operator, vitreoretinal proliferation, retinal wound location, patient age and the operative side. Thirty-six patients presented with lower wounds; 17 patients obtained incomplete results and relapsed within 1 year of surgery. RESULTS: Vitreoretinal proliferation and inferior location of the retinal detachment were found to be poor prognostic factors. No significant differences were found between the other parameters studied. DISCUSSION: A variety of prognostic factors of retinal detachment surgery are now clearly identified (vitreoretinal proliferation, old detachment). A lower location of the detachment constitutes an additional difficulty for retinal applications. Indeed, it is more difficult to perform effective buffering in this type of case. We recommend that retinal detachment be operated internally, to reduce the risk of relapse. CONCLUSION: An inferior location of the retinal wound during retinal detachment appears to be a factor of poor prognosis, but this remains to be ascertained through an ongoing, prospective study.

Female↗
PubMed2005

[Temporal arterious obliteration by Candida endophthalmitis].

We report the case of a 50-year-old woman with a branch retinal artery occlusion caused by acute Candida albicans chorioretinitis, diagnosed based on ophthalmoscopic and angiographic examinations. Although vasculitis is frequent during Candida endophthalmitis, branch obstruction is rare. The thrombosis is probably related to perivascular inflammation rather than septic embolus. We propose antiaggregant therapy when the infection is near the retinal vessels.

Candidiasis↗
PubMed2005

[Ocular lymphoma].

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Eye Neoplasms↗
PubMed2004

Cutaneous leishmaniasis in red kangaroos: isolation and characterisation of the causative organisms.

This is the first report of cutaneous leishmaniasis in kangaroos where infection was acquired within Australia. The diagnosis is based on the clinical criteria used for humans, the lesion histopathology, the detection and isolation of parasites from the lesions, and the analysis of the small subunit ribosomal RNA genes using the polymerase chain reaction. Despite a clear indication that the parasites belong to the genus Leishmania, no assignation to a known Leishmania species could be made using these or other less conserved genetic loci such as the non-transcribed spacer of the mini-exon repeat. As is the case in humans, some but not all animals harbouring lesions had antibodies to the isolated parasites or to several other Leishmania species. The isolated parasites displayed two well characterised Leishmania glycoconjugates, the lipophosphoglycan and proteophosphoglycan. They were infectious for mouse macrophages in vitro and established long-term infection at 33 degrees C but not at 37 degrees C. Our findings raise the possibility of transmission to humans, which may be unrecognised and suggest the possibility that imported species of Leishmania could become endemic in Australia.

Animals↗
PubMed2004

Short report: the use of a polymerase chain reaction to detect Echinococcus granulosus (G1 strain) eggs in soil samples.

Cystic echinococcosis is a re-emerging disease in central Asia. A total of 120 soil samples taken from 30 gardens of rural homesteads in southern Kazakhstan were analyzed for the presence of taeniid eggs using a concentration technique. Of these, 21 (17.5%) were shown to be contaminated with taeniid eggs. These isolated taeniid eggs were further analyzed using a polymerase chain reaction specific for the G1 (sheep) strain of the tapeworm Echinococcus granulosus, and five samples were shown to be positive. This study demonstrates the widespread contamination of the environment with E. granulosus eggs in an Echinococcus-endemic area and thus the potential for indirect transmission of E. granulosus to humans from such sources.

Animals↗
PubMed2003

Infectivity of Cryptosporidium parvum genotype I in conventionally reared piglets and lambs.

Parasites of the genus Cryptosporidium are intracellular parasites that occur throughout the animal kingdom and have been reported in many species of mammals, including human. Most infections in humans are caused by two C. parvum genotypes, genotype I and genotype II; these are the human and the bovine (zoonotic) genotypes, respectively. Successful experimental infection of Cryptosporidium parvum genotype I "human genotype" is described in four conventionally reared piglets and in a lamb. The inoculum was originally obtained from two diarrheic children, and the Cryptosporidium genotypes were determined by PCR and rDNA sequencing. The infective dose was between 10(6) and 2 x 10(6) oocysts. No clinical signs were observed in the infected animals, except in a piglet that showed watery diarrhea. The oocyst shedding period in positive animals ranged between 4 and 10 days. Histopathologic examination of the gastrointestinal tract of two positive piglets revealed shortening of the villi and denudation of the villous tips of the jejunum. In one piglet, the colon mucosa revealed numerous Cryptosporidium oocysts. The storage time of the inocula (< or =3 weeks in PBS at 4 degrees C) and the age of the animal (newborn) were important for the successful induction of infection.

Animals↗
PubMed2003

Molecular tools for studies on the transmission biology of Echinococcus multilocularis.

Two novel approaches for diagnosis of intestinal Echinococcus multilocularis infection, the detection of E. multilocularis-specific coproantigens in ELISA and of copro-DNA by PCR, have been successfully implemented. These methods have proven their value for the post mortem and the intra vitam diagnosis of E. multilocularis in definitive hosts. They have also made novel approaches possible to study the transmission biology of the parasite as they allow detection of the infection in faecal samples collected in the environment. Coproantigen detection is the diagnostic method of choice as it is sensitive, fast and cheap. Studies on faecal samples collected in the field revealed that coproantigen detection did reflect the different prevalences in fox populations as assessed from foxes at necropsy and also the effect of deworming efforts in foxes as achieved by long-term distribution of praziquantel-containing baits. The use of PCR for routine diagnostic or large-scale purposes is hampered by the fact that DNA extraction from faecal material is a very laborious task. Therefore, PCR is rationally used for confirmatory purposes of copro-antigen-positive samples. As taeniid eggs cannot further be differentiated morphologically, PCR is the method of choice to identify E. multilocularis infections in faecal or environmental samples containing taeniid eggs. In intermediate rodent hosts, PCR is routinely used in epidemiological studies for identifying E. multilocularis from liver lesions which are often very small, atypical or calcified.

Animals↗
PubMed2003

Overt fatal and chronic subclinical Encephalitozoon cuniculi microsporidiosis in a colony of captive emperor tamarins (Saguinus imperator).

The course of an infection with the microsporidian Encephalitozoon cuniculi in a colony of captive emperor tamarins (Saguinus imperator) is described. In two litters, the infection was associated with overt disease and death of all infants. Immunohistochemistry for E. cuniculi showed generalized infections, and histopathologic evaluation revealed systemic vasculitis and disseminated mixed inflammatory cell infiltration with and without necrosis in several organs. Serologically, some of the juvenile animals presented with high titres for Encephalitozoon, while the adults had low titres. The E. cuniculi "dog strain" was identified by molecular means for the first time in Europe. The origin of the infection appeared to be a pair of breeding adults that originated from the US. Our data suggest that the organism persisted over years in the colony, and that subclinically infected animals most likely were involved in perpetuating the infection. Efforts should be made to ascertain if this microorganism is present in other captive populations of this endangered monkey species and to prevent its further spreading.

Animals↗