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Infections due to Haemophilus influenzae result in tremendous global morbidity. The conjugated vaccines against H. influenzae type b (Hib) have dramatically reduced the incidence of invasive Hib disease in the routine immunization of infants. The several proteins used as vaccine candidates for this pathogen, but they don't produce efficient immune in animal models against all strains of H. influenzae. This study aimed to determine the diversity of hpd gene nucleotide sequences of Iranian native clinical isolates of H. influenzae as a native vaccine candidate compared to standard strains. Twenty isolates of H. influenzae recovered from different clinical specimens of patients admitted to Milad and Imam Khomeini hospitals, Tehran, Iran. Then, isolates detected and identified as H. influenzae using biochemical tests, and further confirmation through omp6 gene PCR. The hpd gene was amplified by PCR using gene-specific primers, and the amplicons digested with EcoR1. For four isolates, the Amplicon of hpd gene sequenced, and the sequences aligned with sequences harbored in GenBank. Subsequently, sequences were submitted to the EMBL site ( http://www.ebi.ac.uk/embl/ ). EcoR1 restriction enzyme pattern was the same among the 19 clinical isolates, and only one isolate was different. That different one with 3 out of 19 isolates were sequenced. The results showed that the nucleotide sequences and the deduced amino acid sequences for protein D in clinical isolates were highly conserved with similarities >95%. In conclusion, regarding high similarity up to 99% in clinical isolates, protein D can be a novel vaccine candidate against all types of H. influenza from Iran. This finding should be proved with more isolates, and also, evaluate the immunological features of protein D in animal models.

MBL (Metallo-β-lactamases) producing Pseudomonas aeruginosa isolates are the most common opportunistic organisms with multidrug resistance (MDR) in hospital infections. The aim of this study was to determine the frequency of MBL producing isolates, antibiotic resistance pattern, and detection of the related genes using PCR technique. In this descriptive cross-sectional study, 150 clinical samples were collected from different wards (Internal, Surgical, and ICU) of Baqiyatallah Hospital during 2017, and isolates were identified by biochemical, and microbiology tests. Antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method. To detect β-lactamases, Double Disc Synergy Test (DDST) and Metallo-β-lactamase detection test were used. And genes associated with β-lactamases and Metallo-β-lactamases were detected by PCR technique. Data were analyzed by SPSS software through Chi-square statistical test. Of 150 clinical specimens 75 P. aeruginosa isolates recovered, and 68.6% of those were MBLs producers. The highest resistance belonged to Ciprofloxacin (94.66%), followed by Amikacin (93.44%), and no resistance was observed to Polymyxin B. The highest prevalence of genes in P. aeruginosa isolates was reported for vim (100%) and aac6 (95.71%). Results of this study showed that the prevalence of MBLs in patients hospitalized in Baqiyatallah Hospital, Tehran (Iran) was high, which causes resistance to a wide range of antibiotics. Also, due to the lack of resistance to Polymyxin B, this antibiotic is a suitable drug choice for treatment of life threating infections produced by P. aeruginosa in the studied wards, although the toxic effect of it should be considered.