Vignan University

About: Vignan University is a education organization based out in Guntur, Andhra Pradesh, India. It is known for research contribution in the topics: Computer science & Control theory. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

Analysis of antibiotic resistance and virulence patterns in Klebsiella pneumoniae isolated from human urinary tract infections in India.

Abstract: In this study, 504 urine samples collected from patients suffering from urinary tract infection (UTIs) were screened for the presence of Klebsiella pneumoniae. The overall occurrence of Klebsiella spp. and K. pneumoniae was found to be 23·2% (117/504) and 16·8% (85/504) respectively. Antibiotic susceptibility testing of 85 K. pneumoniae isolates was carried out by disc diffusion which revealed alarming levels of antibiotic resistance (ABR). Antimicrobial resistance was prominently observed against cefpodoxime (76·47%) followed by ampicillin (70·59%), ceftriaxone (52·94%), cefoxitin (50·59%), amoxyclav (48·24%), ofloxacin (45·88%), cefotaxime (44·71%), cefepime (43·53%) and doxycycline hydrochloride (40%). A small percentage of strains also exhibited resistance to other antimicrobials in the range of 7-35%. Around 77·6% of the isolates were found to be resistant to three or more antibiotic classes and 66·7% of the isolates had multiple antibiotic resistance index values >0·2. Screening of virulence genes in 85 K. pneumoniae isolates revealed that uge gene was the most predominant (11/85, 12·9%), followed by rmpA (9/85, 10·5%), kfu (4/85, 4·7%) and aerobactin genes (2/85, 2·35%). Further, the overall percentage of biofilm producers were found to be 17·65% (15/85). This study warrants hospitals and health care centres to reduce misuse of antibiotics and manage UTI with appropriate treatment after performing antibiotic susceptibility testing.

A Divide and Conquer Technique for the Contention Window to improve the QoS of MAC

Abstract: Efficient Quality of Service (QoS) has become new challenge in Wireless Local Area Networks (WLANs). Voice over Internet Protocol (VoIP) is an important service with strict quality of requirements in Wireless Local Area Network (WLANs). The IEEE802.11e introduced a contention window based technique that is Enhanced Distribution Channel Access (EDCA) that provides a prioritized traffic to guarantee minimum bandwidth needed for time critical applications, through modifications to the medium access control layer. The number of nodes in the network are less the performance of this technique is good, if the number of nodes has increased randomly, the Static behavior of EDCA will show the effect on network usage by increasing the congestion level leads to packet loss in the networks, which intern leads to bad performance and poor link utilization whenever the demand for link utilization increases. Availability of techniques IEEE802.11a and IEEE802.11e proposed new adaptive differentiation techniques for resetting the value of contention window to improve the quality of service. In this paper we proposed a Novel frame work by setting the contention window based on the Divide and Conquer strategy which in turn leads to efficient Quality of Service (QoS) by reducing the channel congestion level even if we have more number of nodes in the network and also reducing the packet loss and packet delay in Wireless Local Area Networks.

Design, Synthesis, Molecular Docking and Biological Evaluation of 1-(benzo[d]thiazol-2-ylamino)(phenyl)methyl)naphthalen-2-ol Derivatives as Antiproliferative Agents

Abstract: A class of 1-((benzo[d]thiazol-2-ylamino)(phenyl)methyl)naphthalen-2-ol derivatives (4a-t) has been synthesized in good yields through a three component coupling reaction. The newly synthesized compounds were evaluated for their in vitro antiproliferative activity against five cell lines such as DU145 (human prostate cancer), MDA-MB-B231 (human breast cancer), SKOV3 (human ovarian cancer), B16-F10 (mouse skin melanoma) and CHO-K1 (Chinese hamster ovary cells), a noncancerous cell line. In vitro inhibitory activity indicates that compounds 4a, 4b, 4c, 4d, 4g, 4j, and 4o exhibited potent anti-proliferative behavior. Among them, compounds 4g, 4j and 4o found to be the most active members exhibiting remarkable growth inhibitory activity. Molecular docking facilitates to investigate the probable binding mode and key active site interactions in tubulins α and β proteins. The docking results are complementary to experimental results.