Prevalence of Chlamydia trachomatis infections in symptomatic women by polymerase chain reaction (PCR) immunofluorescence and Giemsa stain

Chlamydia trachomatis is a ubiquitous human pathogen that is responsible for the most prevalent bacterial sexually transmitted disease worldwide. Studies show that polymerase chain reaction (PCR) is more sensitive than cellular culture for detection of C. trachomatis infections. The aim of this study is to compare different laboratory methods, including Giemsa staining, direct immunofluorescence assay (DFA) and PCR for detection of C. trachomatis in women with urethral symptoms. In this study, 130 women with urethral symptoms admitted in the gynecology clinic, were used and specimens were obtained with endocervical swab for Giemsa staining, DFA and PCR. All the cases underwent these three techniques. Demographic data and the medical history of patients were obtained by direct interview; however, the mean age of cases was 33.8±9.06. Clinical symptoms included abnormal vaginal discharge in 101 cases (77.7%), spotting in 14 cases (10.8%), dysmenorrheal in 7 cases (5.4%), irritation in 6 cases (4.6%) and dysuria in 2 cases (1.5%). In DFA technique, 5 cases (3.8%) were positive and 3 (2.3%) were suspicious, while in the PCR technique, 6 cases (4.6%) were positive for C. trachomatis. However, 3 suspicious cases with DFA were negative in PCR. There was no positive case for C. trachomatis in Giemsa staining. In conclusion, C. trachomatis was not frequent in this study and it can be concluded that this infection was not a major hygienic problem in the same populations that were previously studied. Consequently, the causes that necessitate monogamy could be related to religious causes. Frequency of Chlamydia detection of DFA and PCR was same in the two groups. Nonetheless, Giemsa staining is not a reliable method for evaluating C. trachomatis.Key words: Chlamydia trachomatis, polymerase chain reaction (PCR), direct immunofluorescence assay (DFA)

Does routine repeat testing of critical laboratory values improve their accuracy?

Background: Routine repeat testing of critical laboratory values is very common these days to increase their accuracy and to avoid reporting false or infeasible results. We figure that repeat testing of critical laboratory values has any benefits or not. Methods: We examined 2233 repeated critical laboratory values in 13 different hematology and chemistry tests including: hemoglobin, white blood cell, platelet, international normalized ratio, partial thromboplastin time, glucose, potassium, sodium, phosphorus, magnesium, calcium, total bilirubin and direct bilirubin. The absolute difference and the percentage of change between the two tests for each critical value were calculated and then compared with the College of American Pathologists/Clinical Laboratory Improvement Amendments allowable error. Results: Repeat testing yielded results that were within the allowable error on 2213 of 2233 specimens (99.1). There was only one outlier (0.2) in the white blood cell test category, 9 (2.9) in the platelet test category, 5 (4) in the partial thromboplastin time test category, 5 (4.8) in the international normalized ratio test category and none in other test categories. Conclusion: Routine, repeat testing of critical hemoglobin, white blood cell, platelet, international normalized ratio, partial thromboplastin time, glucose, potassium, sodium, phosphorus, magnesium, calcium, total bilirubin and direct bilirubin results does not have any benefits to increase their accuracy

Negative HER2/neu amplification using immunohistochemistry and chromogenic in situ hybridization techniques in skin melanoma cases

Background: This study was performed to evaluate the amplification of HER-2/neu in patients with melanoma. Materials and Methods: Amplification of HER-2/neu was evaluated in a group of patients with melanoma, referred to two referral centers in Tehran, using immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH) techniques. Results: Forty patients with mean age 57.9±19.5 years were enrolled in this study. The most frequent type of melanoma was acral, while lower limbs were the most frequent sites. The amplification of HER2/ neu was negative in 97.5 of patients with IHC and in 100 of patients with CISH technique. Only one case (2.5) shows weak positive staining (+2) in IHC method. Fifty five percent of melanoma was ulcerative, and the most common stages of tumors were stages 4b and 3b. More than 47 of cases were in Clark level III, while the mean of Breslow thickness was 3.56±2.87 mm. The stage of the case that showed weakly positive staining (2+) in IHC was 4b. Conclusions: The amplification of HER2/neu biomarker was negative in patients with melanoma, using both CISH and IHC techniques

Investigating The Frequency of Serrated Polyps/Adenomas and Their Subtypes in Colonic Polyp Samples

BACKGROUND: The purpose of this study was to determine the frequency of Serrated polyps of colonic polyps samples in Hazrate Rasoule Akram Hospital over ten years. MATERIALS: The target group in this study was patients with colonic polyps in Hazrate Rasoule Akram Hospital. Pathologic evaluation of these patients was done. Serrated polyps, by location, gender, age and type of polyps were divided and frequency of them were determined separately. RESULTS: Of 381 patients studied, 224 (58.79) and 157(41.20) were males and females, respectively. Mean age of patients was 59.25 years. In initial diagnosis, frequency of Adenomatous polyp, Hyperplastic polyp and Mixed polyp were 92.44 and 5.33, and 2.22, respectively. In final diagnosis (Second evaluation), frequency of Adenomatous polyp, Hyperplastic polyp, Mixed polyp, Sessile Serrated Adenoma/ Polyp, Traditional Serrated Adenoma and SPU (Serrated Polyp Unclassifiable) were 90.44, 4.88, 2.44, 1.11, 0.66 and 0.44, respectively. 72.13 and 27.86 of polyps were low grade dysplasia and high grade dysplasia, respectively. According to the results of this study, the incidence of all types of polyps detected was more in men than women. Rectum and sigmoid were most abundant in the area polyp in both initial and final diagnosis. CONCLUSION: Despite the low prevalence of Serrated polyps in patients, early diagnosis is the best action to reduce morbidity and mortality. Probability of the risk of progression from low grade to high grade dysplasia and transforming into Adenocarcinoma is high in Serrated polyps

Evaluation of phenotypic and genotypic characteristics of carbapnemases-producing enterobacteriaceae and its prevalence in a referral hospital in Tehran city

Background & Objective: Carbapenem-resistant Enterobacteriaceae is a growing concern worldwide including Iran. The emergence of this pathogen is worrying as carbapenem is one of the �last-line� antibiotics for treatment of infections caused by multi drug resistant gram- negative bacteria. The main objective of this study was to determine the prevalence of carbapenem-resistant Enterobacteriaceae in a referral hospital in Tehran, Iran. Methods: In this study, all positive isolates of Enterobacteriaceae recorded in blood, urine, and other body fluids were studied during April 2017 to April 2018 in a referral hospital in Tehran. All cases of resistance to carbapenems were first tested by modified Hodge test. All cases with positive or negative test, after gene extraction, were examined genotypically based on the primers designed for the three Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), and OXA-48 genes by conventional PCR method. Results: 108 isolates (13.6) were resistant to all cephalosporins as well as to imipenem and meropenem. In a genotypic study, including 45 isolates, 13 isolates were positive for OXA-48 gene, 11 isolates for OXA-48 and NDM genes, 11 isolates for OXA-48, NDM and KPC genes, 4 isolates for OXA-48 genes and KPC, 3 isolates for NDM, one isolate for KPC. On the other hand, two isolates were negative for all three genes examined. Conclusion: OXA-48 gene was one of the most common genes resistant to carbapenems in Iran. According to studies, the prevalence of antibiotic resistance in Iran is rising dramatically, which reduces the choice of antibiotics to treat severe infections in the future. © 2020, Iranian Society of Pathology. All rights reserved

Induction of humoral immune responses and inhibition of metastasis in mice by a VEGF peptide-based vaccine

Objective(s): Blocking of vascular endothelial growth factor (VEGF) plays a pivotal role in inhibition of metastasis and is a target for development of anti-angiogenic agents. In this study, a peptide-based vaccine was designed and its potential for induction of humoral immune responses, generation of neutralizing antibodies, inhibition of tumor growth and metastasis was determined. Materials and Methods: With online bioinformatics tools, a fragment of the VEGF-A was selected for a peptide-based vaccine. To enhance its antigenicity, the peptide was conjugated with Keyhole limpet hemocyanin and used to immunize mice. Then, the polyclonal anti-VEGF antibody titer was measured and its effect on proliferation of HUVEC cell line was investigated by MTT assay. Finally, we checked the effect of the peptide on tumor growth, metastasis, and survival rates in a mouse model of cancer. Results: The bioinformatics analysis of the selected region confirmed dis-similarity of the peptide with any other human protein and its acceptable antigenicity to stimulate a tumor-specific humoral response. Anti-VEGF antibody titers were significantly greater in vaccinated mice than in controls. IgG antibody from mice immunized with recombinant VEGF-A inhibited HUVEC proliferation (P<0.0001). Tumors in vaccinated mice were significantly smaller than those in controls. Moreover, metastasis was reduced and survival rates increased in the vaccinated group. Conclusion: Production of high-titer antibody against the peptide vaccine indicated that the peptide has the potency to be used as a peptide-based vaccine for humoral inhibition of tumor growth and metastasis. The efficacy of the peptide should be further tested in primate models. © 2020 Mashhad University of Medical Sciences. All rights reserved

A New Framework for Reactive Power Market Considering Power System Security

This paper presents a new framework for the day-ahead reactive power market based on the uniform auction price. Voltage stability and security have been considered in the proposed framework. Total Payment Function (TPF) is suggested as the objective function of the Optimal Power Flow (OPF) used to clear the reactive power market. Overload, voltage drop and voltage stability margin (VSM) are included in the constraints of the OPF. Another advantage of the proposed method is the exclusion of Lost Opportunity Cost (LOC) concerns from the reactive power market. The effectiveness of the proposed reactive power market is studied based on the CIGRÉ-32 bus test system

Joint market clearing in a stochastic framework considering power system security

This paper presents a new stochastic framework for provision of reserve requirements (spinning and non-spinning reserves) as well as energy in day-ahead simultaneous auctions by pool-based aggregated market scheme. The uncertainty of generating units in the form of system contingencies are considered in the market clearing procedure by the stochastic model. The solution methodology consists of two stages, which firstly, employs Monte-Carlo Simulation (MCS) for random scenario generation. Then, the stochastic market clearing procedure is implemented as a series of deterministic optimization problems (scenarios) including non-contingent scenario and different post-contingency states. The objective function of each of these deterministic optimization problems consists of offered cost function (including both energy and reserves offer costs), Lost Opportunity Cost (LOC) and Expected Interruption Cost (EIC). Each optimization problem is solved considering AC power flow and security constraints of the power system. The model is applied to the IEEE 24-bus Reliability Test System (IEEE 24-bus RTS) and simulation studies are carried out to examine the effectiveness of the proposed method.Market clearing Stochastic optimization Offer cost Expected interruption cost Lost opportunity cost

Multiobjective clearing of reactive power market in deregulated power systems

This paper presents a day-ahead reactive power market which is cleared in the form of multiobjective context. Total payment function (TPF) of generators, representing the payment paid to the generators for their reactive power compensation, is considered as the main objective function of reactive power market. Besides that, voltage security margin, overload index, and also voltage drop index are the other objective functions of the optimal power flow (OPF) problem to clear the reactive power market. A Multiobjective Mathematical Programming (MMP) formulation is implemented to solve the problem of reactive power market clearing using a fuzzy approach to choose the best compromise solution according to the specific preference among various non-dominated (pareto optimal) solutions. The effectiveness of the proposed method is examined based on the IEEE 24-bus reliability test system (IEEE 24-bus RTS).Reactive power market Total payment function (TPF) Multiobjective Mathematical Programming Voltage security margin (VSM)

Stochastic Congestion Management Considering Power System Uncertainties

Congestion management in electricity markets is traditionally done using deterministic values of power system parameters considering a fixed network configuration. In this paper, a stochastic programming framework is proposed for congestion management considering the power system uncertainties. The uncertainty sources that are modeled in the proposed stochastic framework consist of contingencies of generating units and branches as well as load forecast errors. The Forced Outage Rate of equipment and the normal distribution function to model load forecast errors are employed in the stochastic programming. Using the roulette wheel mechanism and Monte-Carlo analysis, possible scenarios of power system operating states are generated and a probability is assigned to each scenario. Scenario reduction is adopted as a tradeoff between computation time and solution accuracy. After scenario reduction, stochastic congestion management solution is extracted by aggregation of solutions obtained from feasible scenarios. Congestion management using the proposed stochastic framework provides a more realistic solution compared with the deterministic solution by a reasonable uncertainty cost. Results of testing the proposed stochastic congestion management on the 24-bus reliability test system indicate the efficiency of the proposed framework