Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
Add more filters










Publication year range
1.
Arch Razi Inst ; 77(1): 29-36, 2022 02.
Article in English | MEDLINE | ID: mdl-35891741

ABSTRACT

The results of numerous studies have revealed that some deadly scorpion venoms are composed of various bioactive molecules that have significant cytotoxic effects on cancer cells. In this study, the in vivo lethality and cytotoxic effect of Odontobuthus bidentatus venom were evaluated in different cancer cell lines. Through MTT assay, the cytotoxic effects of O. bidentatus scorpion venom were analyzed on the MCF-7, A549, AGS, HepG2, and Ht-29 cancer cell lines and Hu02 normal cells. To this end, six venom fractions were obtained through a Sephadex G-50 column, and the cytotoxic effects of isolated fractions were evaluated on A549 lung cancer cells. The median lethal dose of O. bidentatus scorpion venom was determined at 0.73 mg/kg by intravenous administration of different venom doses in male BALB/c mice according to the Spearman-Karber method. The O. bidentatus scorpion whole venom had a significant cytotoxic effect on MCF-7, A549, and AGS cells. The treatment of A549 cells with various concentrations of fraction F1 showed that this fraction significantly induced growth inhibitory effect on the cells in a dose-dependent manner, compared to untreated cells.


Subject(s)
Neoplasms , Rodent Diseases , Scorpion Venoms , Animals , Male , Mice , Mice, Inbred BALB C , Neoplasms/veterinary , Rodent Diseases/drug therapy , Scorpion Venoms/toxicity , Scorpions
2.
Int Nurs Rev ; 67(1): 76-83, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31762035

ABSTRACT

AIM: The aim of this study was to identify the ethical challenges of novice nurses in the first year of clinical practice. BACKGROUND: Novice nurses experience a lot of ethical complications in the clinical workplace, especially in the first year of clinical practice. These ethical challenges are scarcely studied. METHODS: Current research was a descriptive qualitative study conducted on twelve novice nurses in educational hospitals affiliated to Arak University of Medical Sciences (from August to December 2018)in Iran. Data were collected through semi-structured in-depth interviews, and informed consent was obtained from all participants. Data were analysed using content analysis. RESULTS: A total of 12 nurses participated, the majority of whom were female (8; 66.6%), and their average age was 23.6 years. Findings of this study revealed four main themes: patient: the forgotten part, exposure to inequalities, inattention to professional ethics and facing a state of quandary. Several sub-themes also appeared in this study. CONCLUSION: These findings can reveal a clear picture of the ethical challenges of novice nurses in Iran. They can be used as a guidance for managers, authorities and nursing stakeholders in order to protect and support these nurses. Further research on each concept is suggested. IMPLICATIONS FOR NURSING AND HEALTH POLICY: These findings can be used to inform nursing education, research, management and clinical practice. Meanwhile, the results of this study may be used to formulate a strategy for training nursing managers in order to protect and support the next generation of nurses.


Subject(s)
Education, Nursing , Ethics, Nursing , Morals , Nursing Staff, Hospital , Female , Humans , Iran , Male , Nurse Administrators , Qualitative Research , Young Adult
3.
Phys Chem Chem Phys ; 18(9): 6813-20, 2016 Mar 07.
Article in English | MEDLINE | ID: mdl-26878270

ABSTRACT

An artificial base pair in the center of a duplex DNA oligomer, formed by 2,4-diaminopyrimidine and fluorescent 4-aminophthalimide C-nucleosides, is characterized spectroscopically, with a view towards its use in femtosecond solvation dynamics. Quantum-chemical calculations predict H-bonding energy equivalent to A:T. UV-vis absorption spectra provide insight into local melting at the 4-aminophthalimide modification site. Increase of temperature to nearly the melting temperature of the duplex leads to better hybridisation of the fluorescent nucleoside, contrary to native base pairs. This unusual observation is explained by the NMR solution structure of the duplex. Two conformations are adopted by the artificial pair due to backbone constraints, having either two or one interbase hydrogen bonds. In the latter, hydrogen bonding sites remain accessible for water solvation. The time-resolved dynamic Stokes' shift of 4-aminophthalimide fluorescence is consistent with that of a mixture of a slow and fast species. From the observations, the optimal linkage between 4-aminophthalimide and 2-deoxyribose for fitting into the duplex B-DNA structure is deduced.


Subject(s)
Base Pairing , DNA/chemistry , Nucleic Acid Conformation , Phthalic Acids/chemistry , Pyrimidines/chemistry , Amides/chemistry , Fluorescence , Magnetic Resonance Spectroscopy
4.
Curr Med Mycol ; 2(4): 46-48, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28959795

ABSTRACT

BACKGROUND AND PURPOSE: Invasive fungal infections cause morbidity and mortality in patients with hematologic malignancies and immunosuppression. Although these infections are commonly caused by Candida and Aspergillus species, infections caused by Mucoralean fungi are also on a growing trend. The definitive diagnosis of mucormycosis includes visualization of non-septate hyphae on pathology or growth of Mucoralean fungi culture. Polymerase chain reaction (PCR) is used to diagnose mucormycosis from paraffin blocks; however, it yields discrepant results in diagnosis of mucormycosis from blood samples. In the current study, we sought to examine the efficiency of PCR test for the diagnosis of mucormycosis and aspergillosis. MATERIALS AND METHODS: Thirty-one patients with suspected fungal sinus infection were recruited from the Hematology-Oncology unit in Taleghani Hospital, Tehran, Iran. DNA was extracted and semi-nested PCR was performed. RESULTS: PCR was reported negative for all the 31 serum samples. Our assay had a sensitivity of 1.3 ng and 12 pg for Mucoralean and Aspergillus species, respectively. CONCLUSION: Using serum PCR, we detected Aspergillus and Mucoralean species in patients with suspected fungal sinus infection. While this test may have utility in diagnosis directly from biopsy site, it appears unreliable for use as a noninvasive blood test.

5.
J Integr Neurosci ; 14(2): 195-206, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25990939

ABSTRACT

It has been suggested that quantum coherence in the selectivity filter of ion channel may play a key role in fast conduction and selectivity of ions. However, it has not been clearly elucidated yet why classical coherence is not sufficient for this purpose. In this paper, we investigate the classical vibrational coherence between carbonyl groups oscillations in the selectivity filter of KcsA ion channels based on the data obtained from molecular dynamics simulations. Our results show that classical coherence plays no effective role in fast ionic conduction.


Subject(s)
Bacterial Proteins/physiology , Carbon/chemistry , Ion Channel Gating/physiology , Ion Channels/chemistry , Ion Channels/physiology , Models, Molecular , Animals , Bacterial Proteins/chemistry , Computer Simulation , Ion Channels/genetics , Nonlinear Dynamics , Oxygen , Potassium Channels , Protein Structure, Secondary , Statistics as Topic , Vibration
6.
Article in English | MEDLINE | ID: mdl-25871141

ABSTRACT

There are many controversial and challenging discussions about quantum effects in microscopic structures in neurons of the brain and their role in cognitive processing. In this paper, we focus on a small, nanoscale part of ion channels which is called the "selectivity filter" and plays a key role in the operation of an ion channel. Our results for superposition states of potassium ions indicate that decoherence times are of the order of picoseconds. This decoherence time is not long enough for cognitive processing in the brain, however, it may be adequate for quantum superposition states of ions in the filter to leave their quantum traces on the selectivity filter and action potentials.


Subject(s)
Ion Channels/chemistry , Ion Channels/metabolism , Molecular Dynamics Simulation , Quantum Theory , Brain/cytology , Brain/metabolism , Brain/physiology , Cognition , Protein Conformation , Time Factors
7.
Iran Red Crescent Med J ; 14(7): 402-7, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22997555

ABSTRACT

BACKGROUND: Health care workers (HCWs) are vulnerable populations for infection with blood borne pathogens. This study was conducted to determine occupational exposure to blood and body fluids among HCWs in teaching hospitals in Tehran, Iran. METHODS: A self-structures questionnaire was used to study 650 HCWs during 2006 -2007 in some teaching hospitals in Tehran, Iran. RESULTS: occupational exposure to blood and body fluids to blood and body fluids of patients was noticed in 53.4%. Recapping was the most common cause of niddle stick injuries (26.5%) and 19.9% of HCWs with a history of needlestick or mucosal exposure had sought medical advice from a specialist, 79.4% of these visited a doctor in the first 24 hours after exposure. Twenty percent of people with a history of needlestick or mucosal exposure to human immune deficiency virus positive (HIV(+)) patients received post-exposure prophylaxis and 46.7% tested themselves for seroconversion. 25.8% of HCWs with a history of needlestick or mucosal exposure with HBsAg(+) patients received hepatitis B immunoglobuline (HBIG), all of these had received it in the first 72 hours after exposure. History of vaccination, and reassurance about the effective serum antibody titer was the most frequent reason mentioned in case the individuals did not receive HBIG (56.5%). CONCLUSION: There is a need for further research to investigate why many HCWs do not take prophylactic and essential actions after needle stick or mucosal exposure to body fluids of infected patients.

8.
Rev Sci Instrum ; 82(6): 063108, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21721675

ABSTRACT

A setup for fluorescence upconversion spectroscopy (FLUPS) is described which has 80 fs temporal response (fwhm) for emission in the spectral range 425-750 nm. Broadband phase matching is achieved with tilted gate pulses at 1340 nm. Background from harmonics of the gate pulse is removed and sensitivity increased compared to previous designs. Photometric calibration of the upconversion process is performed with a set of fluorescent dyes. For Coumarin 153 in methanol the peak position, bandwidth, and asymmetry depending on delay time are reported.

9.
J Phys Chem B ; 115(13): 3656-80, 2011 Apr 07.
Article in English | MEDLINE | ID: mdl-21410155

ABSTRACT

In blue-light photoreceptors using flavin (BLUF), the signaling state is formed already within several 100 ps after illumination, with only small changes of the absorption spectrum. The accompanying structural evolution can, in principle, be monitored by femtosecond stimulated Raman spectroscopy (FSRS). The method is used here to characterize the excited-state properties of riboflavin and flavin adenine dinucleotide in polar solvents. Raman modes are observed in the range 90-1800 cm(-1) for the electronic ground state S(0) and upon excitation to the S(1) state, and modes >1000 cm(-1) of both states are assigned with the help of quantum-chemical calculations. Line shapes are shown to depend sensitively on resonance conditions. They are affected by wavepacket motion in any of the participating electronic states, resulting in complex amplitude modulation of the stimulated Raman spectra. Wavepackets in S(1) can be marked, and thus isolated, by stimulated-emission pumping with the picosecond Raman pulses. Excited-state absorption spectra are obtained from a quantitative comparison of broadband transient fluorescence and absorption. In this way, the resonance conditions for FSRS are determined. Early differences of the emission spectrum depend on excess vibrational energy, and solvation is seen as dynamic Stokes shift of the emission band. The nπ* state is evidenced only through changes of emission oscillator strength during solvation. S(1) quenching by adenine is seen with all methods in terms of dynamics, not by spectral intermediates.


Subject(s)
Flavins/chemistry , Quantum Theory , Solvents/chemistry , Spectrum Analysis, Raman , Time Factors , Vibration
10.
Int Surg ; 60(8): 405-7, 1975 Aug.
Article in English | MEDLINE | ID: mdl-1158617

ABSTRACT

1. Among all tissue examinations, 8.6% were on male urogenital organs, of which 2.9% were for carcinoma of the prostate. Biopsies of the prostate comprised a large percentage of all male urogenital biopsies. Since the specimens examined by various pathological laboratories in Tehran were received from all over the country, comparison of these statistics is significant. 2. Male urogenital tumors comprised 6.7% of male biopsies, of which 2.7% were for tumors of the prostate. 3. Male urogenital cancers comprised 2.3% of biopsies examined, of which only four were prostatic carconomas. Carcinoma of the prostate was the rarest cancer of the male urogenital organs in Iran. 4. We found 933 cases of cancer of male urogenital organs in 31 years. This comprised 6% of all male cancers, of which only 0.33% were carcinoma of the prostate. 5. Bladder carcinomas were the commonest and prostate carcinomas the rarest among males. 6. We found that 97% of prostate tumors were benign and 3% were malignant. Prostatic carcinoma was four times more prevalent among high income patients than among low income patients. 7. Benign tumors were most common in the 40 to 70 age groups, whereas the peak incidence for carcinoma of this organ was 50 to 70 years of age. 8. No particular clinical symptoms were found. Most patients reported pollakiuria, dysuria or urinary retention. 9. The initial growth site of tumors in the few cases that we were able to study was in the cortex region, especially from the posterior lobe. 10. Histological types of tumor found did not differ from other figures reported. We found no sarcomas. 11. No systematic study of asymptomatic nodules of carcinoma of the prostate has been made and we have never found any signs of such solitary nodules. This may be due to the low average age and the rarity of malignancy of the prostate in Iran. 12. The frequency of death in Iran due to carcinoma of the prostate is impossible to state since death certificates, in the majority of cases, specify secondary symptoms of the disease and not the original disease. 13. The incidence of prostatic carcinoma in the provice of Fars was five times greater and in Isfahan four times greater than in the province of Tehran. However, the figures for Tehran were compiled over the last 31 years, whereas the figures for Isfahan and Shiraz are only for the last ten years, and comparison of these three sets of figures may not be accurate. 14. Carcinoma of the prostate is not as common in Iran as it is in Europe and America. It is rather rare in Iran and compares favorably with figures for the Near Eastern and Far Eastern countries. The Middle Eastern countries of Lebanon, Israel and Afghanistan are very similar in incidence to Iran. In other countries in our region, the incidence is 1.8%.


Subject(s)
Prostatic Neoplasms/epidemiology , Adult , Aged , Carcinoma/epidemiology , Humans , Iran , Kidney Neoplasms/epidemiology , Male , Middle Aged , Prostatic Neoplasms/pathology , Socioeconomic Factors , Testicular Neoplasms/epidemiology , Urinary Bladder Neoplasms/epidemiology
SELECTION OF CITATIONS
SEARCH DETAIL
...