A Map of Dielectric Heterogeneity in a Membrane Protein: the Hetero-Oligomeric Cytochrome b 6 f Complex

The cytochrome b6f complex, a member of the cytochrome bc family that mediates energy transduction in photosynthetic and respiratory membranes, is a hetero-oligomeric complex that utilizes two pairs of b-hemes in a symmetric dimer to accomplish trans-membrane electron transfer, quinone oxidation–reduction, and generation of a proton electrochemical potential. Analysis of electron storage in this pathway, utilizing simultaneous measurement of heme reduction, and of circular dichroism (CD) spectra, to assay heme–heme interactions, implies a heterogeneous distribution of the dielectric constants that mediate electrostatic interactions between the four hemes in the complex. Crystallographic information was used to determine the identity of the interacting hemes. The Soret band CD signal is dominated by excitonic interaction between the intramonomer b-hemes, bn and bp, on the electrochemically negative and positive sides of the complex. Kinetic data imply that the most probable pathway for transfer of the two electrons needed for quinone oxidation–reduction utilizes this intramonomer heme pair, contradicting the expectation based on heme redox potentials and thermodynamics, that the two higher potential hemes bn on different monomers would be preferentially reduced. Energetically preferred intramonomer electron storage of electrons on the intramonomer b-hemes is found to require heterogeneity of interheme dielectric constants. Relative to the medium separating the two higher potential hemes bn, a relatively large dielectric constant must exist between the intramonomer b-hemes, allowing a smaller electrostatic repulsion between the reduced hemes. Heterogeneity of dielectric constants is an additional structure–function parameter of membrane protein complexes

Recurrent Venous Thromboembolism as the Initial Clinical Presentation of Gastric Cancer: A Case Report

Pulmonary thromboembolism (PTE) is a clinically critical disease, misdiagnosis or delayed diagnosis of which can lead to increased rate of mortality. For prevention of recurrence of PTE, recognition of its risk factors or underlying diseases is of great importance. PTE is common in patients with cancer and has high morbidity and mortality rates. Although cancer is a lethal condition, PTE accelerates death in these patients. In the current study, we reported the case of a 50-year-old male presenting with dyspnea, pleuritic chest pain, and non-massive hemoptysis indicating pulmonary embolism. Anticoagulant therapy was initiated, but after 12 days of treatment, new deep vein thromboses in the left upper and right lower limbs were diagnosed. However, no specific risk factors or laboratory abnormalities were detected. History of weight loss during the recent months encouraged further investigation for ruling out malignancy, which led a diagnosis of gastric adenocarcinoma. He did not have any complaints of gastrointestinal disorders

The Importance of Post Coital Bleeding in Countries with Low Level Cervical Cancer Screening

Background & Objective: This study aimed to examine the extent to which postcoital bleeding (PCB) can be a predictive factor for cervical cancer. Materials & Methods: In this observational study we selected and evaluated 280 females with PCB referred to Kowsar Hospital of Qazvin, Iran from 2017 to 2019. Results: Among the 189 patients diagnosed as normal in their Pap smear results, one patient had cancer in her biopsy results. A closer look at the biopsy results of the patients showed 45 patients as normal, 64 patients with cervical infection, 31 patients with polyp cervix, 45 patients with cervical intraepithelial neoplasia 1 (CIN 1), and one patients with squamous cell carcinoma (SCC). Among 63 patients diagnosed with atypical squamous cells of undetermined significance (ASCUS), three showed CIN 2 and CIN 3 in their biopsies. Furthermore, out of 21 patients with low-grade squamous intraepithelial lesion (LSIL), three patients had CIN 2 and CIN 3, one patient had carcinoma, and one had SCC. In addition, all of the patients with highgrade squamous intraepithelial lesion (HGSIL) were diagnosed with CIN 2, CIN 3, and SCC. Conclusion: Because of the higher rate of cervical cancer in women with PCB and inconsistent screening programs in developing countries, it is essential to carefully consider the symptoms of PCB despite having a normal Pap smear

Role of Clinical Pharmacists in Early Detection, Reporting and Prevention of Medication Errors in a Medical Ward

Background: Drug utilization evaluation (DUE) is an effective process in order to identifying variability in drug use and subsequent application of effective interventions for improving  patient outcomes. In this study, appropriate uses of drugs were evaluated by pharmacy service. Methods: A prospective, interventional study was designed for determining frequency and type of clinical pharmacists’ interventions and medication errors occurred in the infectious disease ward of Loghman hospital, affiliated to Shahid Beheshti University of Medical Sciences, Tehran, Iran during 8 months.   Results: During the 8 months of the study period, 498 errors were detected among 419 patients that admitted to infectious disease ward of Loghman hospital. Most common errors were related to DVT prophylaxis, SUP and vancomycin monitoring.   Discussion: Our result showed that clinical pharmacy interventions can have an important role in reducing adverse drug events and their activities can be effective for reducing of medication error

Effects of different extracts of Eucalyptus camaldulensis on Trichomonas vaginalis parasite in culture medium

BACKGROUND: Trichomonas vaginalis is considered one of the main causes of vulvovaginitis in women. Metronidazole with vast side effects is now the drug of choice for treatment of this infection. In an attempt to find an alternative drug, the effect of Eucalyptus camaldulensis on this parasite was shown in previous studies. In this investigation, the effect of different extracts of this plant on T. vaginalis in culture medium has been investigated. MATERIALS AND METHODS: Five different extracts including total extract, diethyl ether, chloroform, ethyl acetate, and water fractions were prepared. The extracts were dried using vacuum rotary evaporator and then they were used for in vitro anti-trichomonas experiments. RESULTS: Crude extract of E. camaldulensis showed 80% growth inhibition (GI) in a concentration of 12.5 mg/ml during 24 h. Diethyl ether extract in a concentration of 25 mg/ml showed 100% GI during 24 h. With ethyl acetate extract, 100% GI was detected with the minimum concentration of 12.5 mg/ml in the first 24 h. Finally, water extract in a concentration of 50 mg/ml showed 80% and 100% GI after 48 and 72 h, respectively. CONCLUSION: Ethyl acetate fraction is the extract which showed the highest percentage of GI (100%) with the least concentration (12.5 mg/ml) after 24 and 48 h

Effects of different extracts of Eucalyptus camaldulensis on Trichomonas vaginalis parasite in culture medium

Background: Trichomonas vaginalis is considered one of the main causes of vulvovaginitis in women. Metronidazole with vast side effects is now the drug of choice for treatment of this infection. In an attempt to find an alternative drug, the effect of Eucalyptus camaldulensis on this parasite was shown in previous studies. In this investigation, the effect of different extracts of this plant on T. vaginalis in culture medium has been investigated. Materials and Methods: Five different extracts including total extract, diethyl ether, chloroform, ethyl acetate, and water fractions were prepared. The extracts were dried using vacuum rotary evaporator and then they were used for in vitro anti-trichomonas experiments. Results: Crude extract of E. camaldulensis showed 80% growth inhibition (GI) in a concentration of 12.5 mg/ml during 24 h. Diethyl ether extract in a concentration of 25 mg/ml showed 100% GI during 24 h. With ethyl acetate extract, 100% GI was detected with the minimum concentration of 12.5 mg/ml in the first 24 h. Finally, water extract in a concentration of 50 mg/ml showed 80% and 100% GI after 48 and 72 h, respectively. Conclusion: Ethyl acetate fraction is the extract which showed the highest percentage of GI (100%) with the least concentration (12.5 mg/ml) after 24 and 48 h

Effects of different extracts of Eucalyptus camaldulensis on Trichomonas vaginalis parasite in culture medium.

BACKGROUND Trichomonas vaginalis is considered one of the main causes of vulvovaginitis in women. Metronidazole with vast side effects is now the drug of choice for treatment of this infection. In an attempt to find an alternative drug, the effect of Eucalyptus camaldulensis on this parasite was shown in previous studies. In this investigation, the effect of different extracts of this plant on T. vaginalis in culture medium has been investigated. MATERIALS AND METHODS Five different extracts including total extract, diethyl ether, chloroform, ethyl acetate, and water fractions were prepared. The extracts were dried using vacuum rotary evaporator and then they were used for in vitro anti-trichomonas experiments. RESULTS Crude extract of E. camaldulensis showed 80% growth inhibition (GI) in a concentration of 12.5 mg/ml during 24 h. Diethyl ether extract in a concentration of 25 mg/ml showed 100% GI during 24 h. With ethyl acetate extract, 100% GI was detected with the minimum concentration of 12.5 mg/ml in the first 24 h. Finally, water extract in a concentration of 50 mg/ml showed 80% and 100% GI after 48 and 72 h, respectively. CONCLUSION Ethyl acetate fraction is the extract which showed the highest percentage of GI (100%) with the least concentration (12.5 mg/ml) after 24 and 48 h

Using Chromosomal Abnormalities and Germination Traits for the Assessment of Tritipyrum Amphiploid Lines under Seed-Aging and Germination Priming Treatments

Primary Trans Chromosomal Tritipyrum (PTCT) amphiploid is a new cereal grown in saline soil and brackish water for grain and forage production. We evaluated the tolerance to seed deterioration in 13 promising PTCT lines, assessing accelerated aging (AA) tests by using AA boxes with 100% relative humidity at 40 °C for 72 h. The (Ma/b)(Cr/b)F4 and (St/b)(Cr/b)F4) PTCT lines, more sensitive to seed aging, were primed with NaCl, Salicylic Acid (SA), and Polyethylene Glycol (PEG) to increase the seed vigor of artificially aged seeds. Germination and emergence traits, biochemical parameters, and chromosomal abnormalities induced by artificial aging were measured in deteriorated and not-deteriorated seeds. The highest reduction percentages related to seed vigor were observed in (Ka/b)(Cr/b)F2 (34.52) and La(4B,4D)/b (28.15) lines, while the lowest was found in (Ma/b)(Cr/b)F4 (7.65) and (St/b)(Cr/b)F4 (7.46) lines. Seed aging also increases electrolytes, potassium, and protein leakages. Chromosomal abnormalities are caused by seed aging that interferes with chromosome behaviors during cell division. Seed priming on aged seeds revealed an increase in the germination percentage (GP) with PEG treatment, while the priming by SA showed an increase in seedling traits, such as the seedling length (SL2). In conclusion, we highlighted the potential use of different PTCT lines and the effective use of seed priming on deteriorated seed to enhance seed viability and seedling vigor as a useful tool for sustainable agriculture