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K Chemlal

Publications and source records attributed to K Chemlal.

At least 19 recordsLinked to original sources
PubMed2004

[Syphilis].

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Characterization of an unusual Mycobacterium: a possible missing link between Mycobacterium marinum and Mycobacterium ulcerans.

In an attempt to characterize an unusual mycobacterial isolate from a 44-year-old patient living in France, we applied phenotypic characterizations and various previously described molecular methods for the taxonomic classification of mycobacteria. The results of the investigations were compared to those obtained in a previous study with a set of temporally and geographically diverse Mycobacterium ulcerans (n = 29) and Mycobacterium marinum (n = 29) isolates (K. Chemlal, G. Huys, P.-A. Fonteyne, V. Vincent, A. G. Lopez, L. Rigouts, J. Swings, W. M. Meyers, and F. Portaels, J. Clin. Microbiol. 39:3272-3278, 2001). The isolate, designated ITM 00-1026 (IPP 2000-372), is closely related to M. marinum according to its phenotypic properties, lipid pattern, and partial 16S rRNA sequence. Moreover, fingerprinting by amplified fragment length polymorphism (AFLP) analysis unequivocally classified this strain as a member of the species M. marinum, although it lacked two species-specific AFLP marker bands. However, PCR and restriction fragment length polymorphism analysis based on M. ulcerans-specific insertion sequence IS2404 showed the presence of this element in a low copy number in isolate ITM 00-1026. In conclusion, the designation of this isolate as a transitional species further supports the recent claim by Stinear et al. (T. Stinear, G. Jenkin, P. D. Johnson, and J. K. Davies, J. Bacteriol. 182:6322-6330, 2000) that M. ulcerans represents a relatively recent phylogenetic derivative of M. marinum resulting from the systematic acquisition of foreign DNA fragments.

Adult↗
PubMed2001

Evaluation of PCR-restriction profile analysis and IS2404 restriction fragment length polymorphism and amplified fragment length polymorphism fingerprinting for identification and typing of Mycobacterium ulcerans and M. marinum.

Mycobacterium ulcerans and M. marinum are emerging necrotizing mycobacterial pathogens that reside in common reservoirs of infection and exhibit striking pathophysiological similarities. Furthermore, the interspecific taxonomic relationship between the two species is not clear as a result of the very high phylogenetic relatedness (i.e., >99.8% 16S rRNA sequence similarity), in contrast to only 25 to 47% DNA relatedness. To help understand the genotypic affiliation between these two closely related species, we performed a comparative analysis including PCR restriction profile analysis (PRPA), IS2404 restriction fragment length polymorphism (RFLP), and amplified fragment length polymorphism (AFLP) on a set of M. ulcerans (n = 29) and M. marinum (n = 28) strains recovered from different geographic origins. PRPA was based on a triple restriction of the 3' end region of 16S rRNA, which differentiated M. ulcerans into three types; however, the technique could not distinguish M. marinum from M. ulcerans isolates originating from South America and Southeast Asia. RFLP based on IS2404 produced six M. ulcerans types related to six geographic regions and did not produce any band with M. marinum, confirming the previous findings of Chemlal et al. (K. Chemlal, K. DeRidder, P. A. Fonteyne, W. M. Meyers, J. Swings, and F. Portaels, Am. J. Trop. Med. Hyg. 64:270-273, 2001). AFLP analysis resulted in profiles which grouped M. ulcerans and M. marinum into two separate clusters. The numerical analysis also revealed subgroups among the M. marinum and M. ulcerans isolates. In conclusion, PRPA appears to provide a rapid method for differentiating the African M. ulcerans type from other geographical types but is unsuitable for interspecific differentiation of M. marinum and M. ulcerans. In comparison, whole- genome techniques such as IS 2404-RFLP and AFLP appear to be far more useful in discriminating between M. marinum and M. ulcerans, and may thus be promising molecular tools for the differential diagnosis of infections caused by these two species.

Animals↗
PubMed2001

Mycobacterium ulcerans in wild animals.

Mycobacterium ulcerans infection, or Buruli ulcer, is the third most frequent mycobacterial disease in humans, often causing serious deformities and disability. The disease is most closely associated with tropical wetlands, especially in west and central Africa. Most investigators believe that the aetiological agent proliferates in mud beneath stagnant waters. Modes of transmission may involve direct contact with the contaminated environment, aerosols from water surfaces, and water-dwelling fauna (e.g. insects). Person-to-person transmission is rare. Trauma at the site of skin contamination by M. ulcerans appears to play an important role in initiating disease. Once introduced into the skin or subcutaneous tissue, M. ulcerans multiplies and produces a toxin that causes necrosis. However, the type of disease induced varies from a localised nodule or ulcer, to widespread ulcerative or non-ulcerative disease and osteomyelitis. Although culture of M. ulcerans from a patient was first reported in 1948, attempts to culture the mycobacterium from many specimens of flora and fauna have been unsuccessful. Failure to cultivate this organism from nature may be attributable to inadequate sampling, conditions of transport, decontamination and culture of this fastidious heat-sensitive organism, and to a long generation time relative to that of other environmental mycobacteria. Nevertheless, recent molecular studies using specific primers have revealed M. ulcerans in water, mud, fish and insects. Although no natural reservoir has been found, the possibility that M. ulcerans may colonise microfauna such as free-living amoebae has not been investigated. The host range of experimental infection by M. ulcerans includes lizards, amphibians, chick embryos, possums, armadillos, rats, mice and cattle. Natural infections have been observed only in Australia, in koalas, ringtail possums and a captive alpaca. The lesions were clinically identical to those observed in humans. Mycobacterium ulcerans infection is a rapidly re-emerging disease in some developing tropical countries. The re-emergence may be related to environmental and socioeconomic factors, for example, deforestation leading to increased flooding, and population expansion without improved agricultural techniques, thus putting more people at risk. Eradication of diseases related to these factors is difficult. Whether wild animals have a role in transmission is an important question that, to date, has been virtually unexplored. To address this question, surveys of wild animals are urgently required in those areas in which Buruli ulcer is endemic.

Africa↗
PubMed2001

Deflazacort versus prednisone in patients with giant cell arteritis: effects on bone mass loss.

OBJECTIVE: To compare bone mass loss due to deflazacort versus prednisone in longterm treatment of patients with giant cell arteritis (GCA) in a randomized double blind comparative trial. METHODS: Seventy-four patients were included in a prospective multicenter study. Half received deflazacort (DFZ) and the other half prednisone (PR) for a minimum of 12 months. Calcium and vitamin D supplements were also provided to all subjects. Our intent was (1) to evaluate bone mineral density, using dual energy x-ray absorptiometry, at baseline and comparatively at 3, 6, and 12 mo; vertebral fractures by Meunier score and size variations after 12 mo treatments were also analyzed; (2) to assess calcium/phosphate metabolism modifications in both groups at baseline and after 12 mo. RESULTS: No significant difference was observed between the 2 groups in terms of treatment efficacy. Patients taking PR were slightly older on average versus the DFZ group (74 vs 70 yrs). Bone mass loss between entry and month 12 was not statistically different in the PR group (-0.026 +/- 0.007 g/cm2) compared to the DFZ group (-0.03 +/- 0.005 g/cm2). No significant difference was found in Meunier score variations (0.77 and 1.18 in the PR and DFZ groups, respectively; p = 0.3), nor in vertebral size variations (-0.4 and -0.2 in the PR and DFZ groups, respectively; p = 0.4). There was no difference in calcium/phosphate metabolism evaluations at month 12. CONCLUSION: In older patients taking longterm glucocorticoids who are at risk of osteoporosis, deflazacort did not result in less bone loss than prednisone.

Absorptiometry, Photon↗
PubMed2000

[Streptococcus intermedius Lemierre syndrome: an unusual association].

BACKGROUND: Lemierre's syndrome is a potentially severe though uncommon entity consisting in septic emboli from an internal jugular vein thrombus after oropharyngeal infection. CASE REPORT: A 21-year-old man initially treated for acute pharnygeal infection developed fever and lower chest pain related to multiple pulmonary abscesses. The diagnosis of Lemierre's syndrome was retained due to the association of extensive thrombus formation in the internal jugular vein and Streptococcus intermedius septicemia. DISCUSSION: Lemierre's syndrome is a classical entity whose frequency is probably underestimated. The causal agent is not always an anaerobic germ. Use of anticoagulants is controversial.

Adult↗
PubMed2000

Dramatic improvement of renal dysfunction in a human immunodeficiency virus-infected woman treated with highly active antiretroviral therapy.

We report a single case documenting substantial improvement in the course of human immunodeficiency virus (HIV)-associated, biopsy-proven nephropathy after introduction of highly active antiretroviral therapy. Our case report joins several others recording improvement or stabilization in the course of nephropathy following better control of HIV replication.

Adult↗
PubMed2000

Biochemical and genetic evidence for phospholipase C activity in Mycobacterium ulcerans.

This study reports the existence of phospholipase C and D enzymatic activities in Mycobacterium ulcerans cultures as determined by use of thin-layer chromatography to detect diglycerides in hydrolysates of radiolabeled phosphatidylcholine. M. ulcerans DNA sequences homologous to the genes encoding phospholipase C in Mycobacterium tuberculosis and Pseudomonas aeruginosa were identified by sequence analysis and DNA-DNA hybridization. Whether or not the phospholipase C and D enzymes of M. ulcerans plays a role in the pathogenesis of the disease needs further investigation.

DNA, Bacterial↗
PubMed2000

Evaluation of amplified fragment length polymorphism analysis for inter- and intraspecific differentiation of Mycobacterium bovis, M. tuberculosis, and M. ulcerans.

The usefulness of amplified fragment length polymorphism (AFLP) analysis was evaluated for the discrimination of Mycobacterium bovis (17 strains), M. tuberculosis (15 strains), and M. ulcerans (12 strains) at the inter- and intraspecific level. The AFLP technique is a whole-genome coverage genotypic fingerprinting method based on the selective PCR amplification of modified restriction fragments obtained through a double enzymatic digest and subsequent ligation of double-stranded restriction site-specific adapter oligonucleotides. Selective amplification of ApaI/TaqI templates with primer combination A02-T02 (both having an additional C at their 3' end) generated autoradiographic AFLP fingerprints that were grouped by numerical analysis in two main AFLP clusters allowing clear separation of M. ulcerans (cluster I) from the M. tuberculosis complex members M. bovis and M. tuberculosis (cluster II). Calculation of similarities using the band-based Dice correlation coefficient instead of the Pearson product-moment correlation coefficient revealed a further subgrouping in cluster II. The two resulting subclusters corresponded with the phenotypic identity of M. bovis and M. tuberculosis, respectively, and could also be visually identified by two AFLP marker bands. Because of the relatively low degree of genotypic variation among the AFLP band patterns of the latter two taxa, no correlation could be found with previously reported molecular typing data or with geographical origin. The use of primer combination A02-T01 (the latter having an A as selective base) did not increase the resolving power within the M. tuberculosis complex but resulted in a visual subgrouping of the M. ulcerans strains that was not observed with primer combination A02-T02. Based on the presence or absence of a single AFLP marker band, the M. ulcerans isolates could be unambiguously classified in two continental types corresponding with the African and Australian origin of the strains, respectively. In conclusion, the radioactive AFLP method proved to be a reproducible and reliable taxonomic tool for the differentiation of the three mycobacterial species under study and also demonstrated its potential use for typing of M. ulcerans strains when employing multiple primer combinations.

DNA Fingerprinting↗
PubMed1999

Nodular lesions of the liver revealing multiple myeloma.

Liver involvement in multiple myeloma (MM) has been reported very rarely in living patients. Here we describe a rare case in whom investigation of liver nodules by biopsy, revealed MM. The Role of cytadhesin molecules in the spread of plasma cell neoplasia is discussed and a review of the Literature is given.

Aged↗
PubMed1998

[Superior vena cava thrombosis manifesting as vasomotor facial flushes].

BACKGROUND: The first sign in the reported case of superior vena cava thrombosis secondary to a pacemaker lead, was exceptional: facial flush. CASE REPORT: A 52-year-old woman had a pacemaker for 10 years for rhythm disorders. She developed facial flush triggered by exercise and anteflexion. The clinical examination revealed collateral thoracic circulation, suggesting thrombosis of the superior vena cava which was confirmed by the angiocavogram. DISCUSSION: Vasomotor flush is an uncommon and misleading initial sign of superior vena cava thrombosis. Induction by exercise and anteflexion is characteristic. Due to the increasing number of implanted patients, clinicians should be aware that pacemaker leads are an uncommon cause of superior vena cava thrombosis.

Collateral Circulation↗