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UNLABELLED: Structured to Purpose: Human brucellosis is one of the most common zoonotic infections worldwide, which remains one of the major problems for public health. Despite the World Health Organization's recommendation for human brucellosis treatment, sporadic cases of relapse have been reported. The aim of this study was to assess the susceptibility of Brucella isolates to common antibiotics that are prescribed by the physician for the treatment of brucellosis and also to determine the minimum inhibitory concentration 50% (MIC 50 ) and MIC 90 for these antibiotics. MATERIALS AND METHODS: Forty-eight Brucella strains were collected from patients with acute brucellosis. Species identification was made based on the conventional methods. MIC of rifampin, doxycycline, ciprofloxacin, trimethoprim- sulfamethoxazole, streptomycin, azithromycin and ceftriaxone was determined by E-test. RESULTS: All the 48 Brucella isolates (47 blood samples and one synovial fluid) were identified as Brucella melitensis. No antimicrobial-resistant strains were recognised. Trimethoprim-sulfamethoxazole had the lowest MIC 50 (0.016 µg/ml) and MIC 90 (0.064 µg/ml), whereas MIC 50 and MIC 90 of streptomycin and azithromycin had the highest level at 0.625, 1.5 µg/ml and 0.25, 1 µg/ml, respectively. All the isolates were susceptible to rifampin, and only one of the isolates had a reduced sensitivity to rifampin (1 µg/ml). CONCLUSIONS: Although all the Brucella isolates were susceptible, antimicrobial susceptibility test should be recommended in patients with recurrent brucellosis or life-threatening organ involvement.

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BACKGROUND AND PURPOSE: Candida species are considered a common cause of fungal blood stream infections, which are associated with considerable mortality and morbidity rates, especially in the admitted and immunocompromised patients. Despite the increase in new and available antifungal agents, the emergence of resistant strains is growing. Regarding this, the aim of the present study was to assess the fungal epide-miology of candidemia and the antifungal susceptibility patterns against five current antifungal agents among the patients with prolonged fever, who were admitted to Beheshti Educational Hospital, Kashan, Iran. MATERIALS AND METHODS: This cross-sectional study was conducted on 253 hospitalized patients with prolonged fever despite receiving broad-spectrum antibiotic therapy. Blood samples were collected aseptically, and then cultured using an automated blood culture system and conventional broth culture bottle. Candida isolates were identified at species level using morphological and physiological properties and produced color on the CHROMagar Candida. Furthermore, the antifungal susceptibility testing was performed using (CLSI M27-A3 and CLSI M27-S4) broth microdilution methods. RESULTS: The most positive cultures were detected by the automated blood culture system. C.albicans (%50) was the most prevalent species, followed by C. glabrata (%40), and C. parapsilosis, (%10) respectively .The mortality rate was high (%60) and most patients with candidemia were admitted to the Intensive Care Unit and Neonatal Intensive Care Unit. All isolates were susceptible to amphotericin B, while the highest resistance belonged to caspofungin. CONCLUSION: In this study, high resistance was reported, especially for caspofungin, which can be regarded as the emergence of caspofungin-resistant strains. Regarding this, the establishment of a surveillance and prevention program for the reduction of the emergence of resistant species is necessary.

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It is generally assumed that folding intermediates contain partially formed native-like secondary structures. However, if we consider the fact that the conformational stability of the intermediate state is simpler than that of the native state, it would be expected that the secondary structures in a folding intermediate would not necessarily be similar to those of the native state. beta-Lactoglobulin is a predominantly beta-sheet protein, although it has a markedly high intrinsic preference for alpha-helical structure. The formation of non-native alpha-helical intermediate of beta-lactoglobulin was induced by n-alkyl sulfates including sodium octyl sulfate, SOS; sodium decyl sulfate, SDeS; sodium dodecyl sulfate, SDS; and sodium tetradecyl sulfate, STS at special condition. The effect of n-alkyl sulfates on the structure of native beta-lactoglobulin at pH 2 was utilized to investigate the contribution of hydrophobic interactions to the stability of non-native alpha-helical intermediate. The addition of various concentrations of n-alkyl sulfates to the native state of beta-lactoglobulin (pH 2) appears to support the stabilized form of non-native alpha-helical intermediate at pH 2. The m values of the intermediate state of beta-lactoglobulin by SOS, SDeS, SDS and STS showed substantial variation. The enhancement of m values as the stability criterion of non-native alpha-helical intermediate state corresponded with increasing chain length of the cited n-alkyl sulfates. The present results suggest that the folding reaction of beta-lactoglobulin follows a non-hierarchical mechanism and hydrophobic interactions play important roles in stabilizing the non-native alpha-helical intermediate state.

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