External versus Endoscopic Dacryocystorhinostomy for Primary Acquired Nasolacrimal Duct Obstruction

PURPOSE

The purpose of the study is to compare the surgical outcomes and success rates of external dacryocystorhinostomy (EX-DCR) versus endoscopic endonasal DCR (EN-DCR) for the treatment of primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

This retrospective nonrandomized study was conducted at Farabi Eye Hospital and Noor Eye Hospital, Iran. A review of electronic medical records of all patients with PANDO who underwent EX-DCR or EN-DCR between January 2016 and 2018 was carried out.

RESULTS

A total of 803 patients underwent surgery, of which 618 patients (77%) were managed by EX-DCR and 185 patients (23%) by EN-DCR. The majority of cases (62%) were female. The mean age of the patients in EX-DCR and EN-DCR groups was 40.8 ± 14.2 and 34.3 ± 9.2 years, respectively. EX-DCR resulted in significantly less amount of pain compared to EN-DCR (P < 0.05). The success rate of surgery among EX-DCR and EN-DCR groups was 92.4% and 91.1%, respectively, and did not show statistically significant difference. A higher incidence of intraoperative hemorrhage requiring intervention was noted in the EN-DCR group (16.7% vs. 4.5%). Postoperative patient's satisfaction with EN-DCR and EX-DCR was 73% and 82%, respectively.

CONCLUSION

Both EX-DXR and endoscopic DCR surgeries have high success rates and low incidence of failure. The choice of DCR technique should be based on the experience of the surgeon and patient's lacrimal and nasal anatomy and preferences.

Comparison of pterygium recurrence with and without using postsurgical topical cyclosporin a 0.05%: A randomized clinical trial

Purpose:

To evaluate the efficacy of 3-month administration of topical cyclosporin A (CsA) 0.05% on postoperative recurrence after pterygium surgery.

Methods:

In this randomized clinical trial, 78 patients undergoing pterygium surgery (using the rotational conjunctival flap technique with mitomycin C [MMC]) were enrolled and randomly allocated into the control (n = 39) and case (CsA) (n = 39) groups in a single-blind method. The patients were examined on postoperative days 1, 3, and 7 and months 1, 3, and 6, and their best-corrected visual acuity, intraocular pressure, clinical inflammation, postoperative complications, and recurrence were compared.

Results:

The mean age of patients was 53.22 ± 9.99 years; most (57.7%) of them were men. The two groups were not different in terms of demographics, pterygium size, or pterygium grade. The clinical inflammation at the first and third postoperative months was not different between the groups (P = 0.108 and 0.780, respectively). No serious complications were detected; complication rates were not different between the groups (P = 0.99). The recurrence rate was 5.1% in the case group and 7.7%% in the control group (P = 0.99).

Conclusion:

The present study showed no priority for 3-month administration of CsA 0.05% drops on postoperative outcomes, including prevention of pterygium recurrence, complications, and inflammation after the rotational conjunctival autograft technique with MMC.

Antimicrobial Peptides: Features, Action, and Their Resistance Mechanisms in Bacteria

In recent years, because of increased resistance to conventional antimicrobials, many researchers have started to study the synthesis of new antibiotics to control the disease-causing effects of infectious pathogens. Antimicrobial peptides (AMPs) are among the newest antibiotics; these peptides are integral compounds in all kinds of organisms and play a significant role in microbial ecology, and critically contribute to the innate immunity of organisms by destroying invading microorganisms. Moreover, AMPs may encourage cells to produce chemokines, stimulate angiogenesis, accelerate wound healing, and influence programmed cell death in multicellular organisms. Bacteria differ in their inherent susceptibility and resistance mechanisms to these peptides when responding to the antimicrobial effects of AMPs. Generally, the development of AMP resistance mechanisms is driven by direct competition between bacterial species, and host and pathogen interactions. Several studies have shown diverse mechanisms of bacterial resistance to AMPs, for example, some bacteria produce proteases and trapping proteins; some modify cell surface charge, change membrane fluidity, and activate efflux pumps; and some species make use of biofilms and exopolymers, and develop sensing systems by selective gene expression. A closer understanding of bacterial resistance mechanisms may help in developing novel therapeutic approaches for the treatment of infections caused by pathogenic organisms that are successful in developing extensive resistance to AMPs. Based on these observations, this review discusses the properties of AMPs, their targeting mechanisms, and bacterial resistance mechanisms against AMPs.

Secure SCADA communication by using a modified key management scheme

This paper presents and evaluates a new cryptographic key management scheme which increases the efficiency and security of the Supervisory Control And Data Acquisition (SCADA) communication. In the proposed key management scheme, two key update phases are used: session key update and master key update. In the session key update phase, session keys are generated in the master station. In the master key update phase, the Elliptic Curve Diffie-Hellman (ECDH) protocol is used. The Poisson process is also used to model the Security Index (SI) and Quality of Service (QoS). Our analysis shows that the proposed key management not only supports the required speed in the MODBUS implementation but also has several advantages compared to other key management schemes for secure communication in SCADA networks.