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J Rahal

Publications and source records attributed to J Rahal.

5 recordsLinked to original sources
PubMed1991

Multiple mechanisms of methicillin resistance and improved methods for detection in clinical isolates of Staphylococcus aureus.

The mec gene of a number of clinical methicillin-resistant Staphylococcus aureus isolates exhibiting a variety of heterogeneous expression modes was selectively inactivated by allelic replacement mutagenesis. While the resistance level of each of the transformants was reduced, the methicillin MIC for these transformants was well above the MIC for susceptible laboratory strains of S. aureus and was similar to the methicillin MIC for many contemporary clinical isolates which did not react with the mec-specific DNA probe but which showed a low or borderline level of resistance to methicillin. A number of those strains had no detectable beta-lactamase, and for about half of the isolates that did carry plasmid-borne beta-lactamase, elimination of the plasmid caused only partial reduction of the methicillin MIC or no reduction at all. The findings suggest that many contemporary strains of staphylococci harbor a combination of at least three distinct beta-lactam resistance mechanisms: (i) the mechanism related to the acquisition of the foreign mec gene and (ii) a beta-lactamase-dependent and (iii) a beta-lactamase-independent mechanism, each one of which can provide a certain degree of resistance against penicillinase-resistant beta-lactam antibiotics.

Clavulanic Acid↗
PubMed1991

[Substernal goiters].

In a series of 363 patients operated for goiter, 60 were retrosternal (16.5%). The female incidence although less than in cervical goiters remains predominant (2,5:1). Most patients are in older age group, 68% being above 40 years. The majority of goiters are multinodular and of long duration. Bilateral (37%) and left sided location (43%) were common. The incidence of cancer was 7%, thyrotoxicosis was noted in 5 patients (8%). Most patients were symptomatic (97%). Diagnosis is easily done by physical examination, chest X-Ray and thyroid scintigraphy. Computed tomography might be helpful. Retrosternal goiter is an indication to surgery except in high risk patients. The cervical approach has been used in 98% of cases. There were no post-operative death and no major complications (compressive hematoma, laryngeal nerve paralysis, hypocalcemia).

Adult↗
PubMed1990

Embryonal rhabdomyosarcoma arising in a mature teratoma of the testis: a case report.

We report a case of embryonal rhabdomyosarcoma present in the primary excision of an intratesticular purely mature teratoma. Testicular mature and immature teratomas are usually associated with other germ cell tumors. Nongerminal malignancies that tend to occur in gonadal and extragonadal teratomas are often epithelial. Sarcomas of all types are less frequent but embryonal rhabdomyosarcomas are encountered predominantly. This sarcomatous element can be present in the primary excision or it can appear after chemotherapy in the metastases. Usually, prognosis is dependent on the degree of aggressiveness of the sarcomatous component. A review of the literature reveals that it is unusual for an embryonal rhabdomyosarcoma to develop on purely mature teratoma. We report a case in the testicle. During followup metastases arise rapidly from the purely embryonal rhabdomyosarcomatous component. The accurate diagnosis of this unusual sarcomatous component is of paramount importance because of the implications for therapy.

Adult↗