Female biased adult sex ratio in the Bronze Age cemetery of Shahr-i Sokhta (Iran) as an indicator of long distance trade and matrilocality

OBJECTIVES

This paper starts from the unusual observation of the overrepresentation of females among adults in the cemetery of Bronze Age Shahr-i Sokhta (Seistan, Iran) and explores the post marital residence pattern. By integrating taphonomical (skeletal preservation), anthropological (sex ratio [SR], sexual dimorphism, stress indicators, age at death), archeological (long distance trade indicators, habitation floor area, social role of women), and ancient DNA (heterozygosity levels in X chromosomes) data we test the hypothesis of post marital matrilocality in the site.

METHODS

We computed the SR (pelvis-based sex determination) in a random unpublished adult sample from the cemetery of Shahr-i Sokhta and in two samples previously published by other authors. We used comparative data on SR from: a large Supra Regional multi-chronological sample of sites, n = 47, with 8808 adult sexed individuals, from Southern Europe, Egypt, Middle East, Southern Russia; a Regional Bronze Age sample of sites (n = 10) from Bactria Margiana and Indus Valley with 1324 adult sexed individuals. We estimated the heterozygosity levels in X chromosomes compared with the rest of the autosomes on the assumption that in a matrilocal society females should show lower variability than men.

RESULTS

Adult SR in a sample (n = 549) from Shahr-i Sokhta is 70.5, the overrepresentation of females is shared with Regional Bronze Age sites from Bactria Margiana (SR = 72.09) and Indus Valley (SR = 67.54). On the contrary, in a larger Supra Regional multi-chronological sample of sites, mean SR ranges between 112.7 (Bronze Age) and 163.1 (Middle Ages). Taphonomical and anthropological indicators do not explain the overrepresentation of female skeletons. Archeological indicators suggest a high social status of women and that the society was devoted to long range trade activities. heterozygosity levels in X chromosomes are in agreement with a matrilocal society.

CONCLUSIONS

Indicators suggest that Bronze Age Shahr-ì Sokhta was a matrilocal society and that long distance trade was an important economic factor producing an overrepresentation of adult female skeletons in the cemetery.

Potential of Pinus eldarica Medw. tree bark for biomonitoring polycyclic aromatic hydrocarbons in ambient air

Urban trees' biomonitoring of pollutants such as polycyclic aromatic hydrocarbons (PAHs) yields pertinent and useful data for air pollution management. The aim of this study was to biomonitor PAHs in pine (Pinus eldarica Medw.) trees in the city of Isfahan and identify their sources. In total, 34 samples of outer bark of the trees were collected and their contents of 16 EPA PAHs were analyzed. With a median value of 136.3 ng/g, the total PAH contents in tree barks varied from 53.4 to 705.2 ng/g. The average values of the diagnostic ratios for Ant/(Ant + Phe), Flu/(Flu + Py), BaA/(BaA + Chr) and IP/(IP + BP) were 0.19, 0.49, 0.45 and 0.49, respectively, revealing the PAHs majority source of pyrogenic. Meanwhile, principal component analysis showed two major types of PAHs sources including pyrogenic (fossil fuel combustion and industrial activities) and petrogenic (uncombusted) sources. The average ratio An/(An + Phe) and Flu/(Flu + Py) in bark samples was close to their relevant ratios in ambient air which demonstrated the potential use of this approach for biomonitoring of PAHs.

Abnormal findings in fetal echocardiography and maternal disease: A cross-sectional study

Background

Congenital cardiovascular malformation is the most common group of birth defects. Fetal echocardiography is highly sensitive and specific in the diagnosis of congenital heart disease in low- and high-risk populations.

Objective

This study aimed to assess abnormal findings in fetal echocardiography and maternal disease.

Materials and Methods

This cross-sectional study was performed on 114 pregnant women referred to Afshar hospital, Yazd, Iran from October 2016 to March 2017. All pregnant women underwent fetal echocardiography through fetal heart screening protocol, which is administered by the international society of ultrasound in obstetrics and gynecology guidelines. Data collected included referral cause, gestational age, maternal age, gravida, and final diagnosis after an accurate fetal echocardiography.

Results

The mean gestational age was 20 wk. The most common referral cause of pregnant women included diabetes (36.8%), fetal arrhythmia (14%), high maternal age (7%), and echogenic focus on ultrasound (6.1%). The most common postpartum findings were normal (68.4%), cardiac abnormalities (17.6%), and arrhythmias (14%). In postnatal echocardiography, the results were consistent with fetal echocardiography except in 2 women.

Conclusion

This study showed that fetal echocardiography can be used in the early diagnosis and treatment of congenital heart diseases.

Seasonal trend and source identification of polycyclic aromatic hydrocarbons associated with fine particulate matters (PM2.5) in Isfahan City, Iran, using diagnostic ratio and PMF model

Particulate matters (PMs) and their associated chemical compounds such as polycyclic aromatic hydrocarbons (PAHs) are important factors to evaluate air pollution and its health impacts particularly in developing countries. Source identification of these compounds can be used for air quality management. The aim of this study was to identify the sources of PM_2.5-bound PAHs in Isfahan city, a metropolitan and industrialized area in central Iran. The PM_2.5 samples were collected at 50 sites during 1 year. Source identification and apportionment of particle-bound PAHs were carried out using diagnostic ratios (DRs) of PAHs and positive matrix factorization (PMF) model. The results showed that the concentrations of PM_2.5 ranged from 8 to 291 μg/m³ with an average of 60.2 ± 53.9 μg/m³, whereas the sum of concentrations of the 19 PAH compounds (ƩPAHs) ranged from 0.3 to 61.4 ng/m³ with an average of 4.65 ± 8.54 ng/m³. The PAH compounds showed their highest and lowest concentrations occurred in cold and warm seasons, respectively. The mean concentration of benzo[a]pyrene (1.357 ng m^-3) in December-January, when inversion occured, was higher than the Iranian national standard value showing the risk of exposure to PM_2.5-bound PAHs. Applying DRs suggested that the sources of the PAHs were mainly from fuel combustion. The main sources identified by the PMF model were gasoline combustion (23.8 to 33.1%) followed by diesel combustion (20.6 to 24.8%), natural gas combustion (9.5 to 28.4%), evaporative-uncombusted (9.5 to 23.0%), industrial activities (8.4 to 13.5%), and unknown sources (2.8 to 15.7%). It is concluded that transportation, industrial activities, and combustion of natural gas (both in residential-commercial and industrial sectors) as the main sources of PAHs in PM_2.5 should be managed in the metropolitan area, particularly in cold seasons.

Bioaccumulation of heavy metals in Stachys inflata and Scariola orientalis affected by particulate matters of a cement factory in central Iran

Industrial activities can affect accumulation of pollutants (e.g., heavy metals (HMs)) by plants and influence their entrance to the food chain. This research was carried out on accumulation of HMs including chromium (Cr), lead (Pb), and zinc (Zn) by two plants Stachys inflata and Scariola orientalis grown in natural grasslands in vicinity of a national park where they are influenced by dispersion of particulate matter (PM) through Sarooj Cement Factory in central Iran. The PM spatial dispersion of the factory was determined using the AERMOD model. Soil and vegetation samples were collected based on the modeled PM levels to analyze their HM contents. Bioconcentration factor (BCF) and transfer factor (TF) from root to shoot were determined in two widespread plants of the region: Stachys inflata and Scariola orientalis. The mean concentration of HMs in the soil samples was as follows: Zn (145.39 mg/kg) > Pb (78.52 mg/kg) > Cr (32.69 mg/kg) which was significantly correlated with simulated PM concentrations. This indicated the common source and distribution pattern of HMs which affected their accumulation in plants. TF and BCF values of the HMs were higher in Scariola orientalis than those of Stachys inflata, especially for Cr showing potentially higher risk to enter the food chain. The results showed that HM concentration in the soil as well as their accumulation by plants were correlated with the simulated PM deposition and not with linear distance from the factory.

Promoting knowledge sharing performance in a knowledge management system: do knowledge workers’ behavior patterns matter?

Purpose

This paper aims to identify the impact of demographical and organizational variables such as age, gender, experiences use of knowledge management system (KMS), education and job level on knowledge sharing (KS) performance of knowledge workers in knowledge activities of a KMS. Specifically, it seeks to explore that is there any relationship between the KS behavior patterns of high KS performance knowledge workers with their performance. Furthermore, this study using its conceptual attitude model aims to show that whether knowledge workers’ behavior patterns in sharing information and knowledge throughout a KMS have any specific effect or not.

Design/methodology/approach

This paper proposed a framework to mine knowledge workers’ raw data using data mining techniques such as clustering and association rules mining. Also, this research uses a case-based approach to a knowledge-intensive company in Iran that works in the field of information technology with 730 numbers of workers.

Findings

Findings suggest that demographical and organizational variables such as age, education and experience use of KMS have positive effects on knowledge worker’s KS behavior in KMSs. In fact, people who have lower age, higher education degrees and more experience use of KMS, have more participation in KS in KMS. Also, results depict that the experienced use of KMS has the most impact on the intention of KS in this KMS. Findings emphasize on the importance of the influence of the behavioral, organizational environments and psychological factors such as reward system, top management support, openness and trust, on KS performance of knowledge workers in the KMS. In fact, according to data, the KMS reward system caused to increasing participation of the users in KS, also in each knowledge activity that top managers participate in, the scores were higher.

Practical implications

This research helps top managers in designing policies and strategies to improve the participation of knowledge workers in KS and helps human resource managers to improve their membership policies. Also, assist Information Technology (IT) managers to enhance KMSs’ design to leverage with organization strategies in the field of improving KS and encourage people to participate in KMS.

Originality/value

This research has two key values. First, this paper applies a data mining framework to mining and analyzing data and this paper uses actual data of a KMS in a specialist company in Iran, with about 27,740 real data points. Second, this paper investigates the impact of demographical and organizational attributes on KS behavior, which little is empirically known about the impact of demographical variables on KS intention.

Quantitative risk assessment of accidental points in the area of Shahid Beheshti field to Abuzar Square in Yazd with the method of accidents rate - severity index

Introduction: Accidents are one of the biggest public health problems in the world. At the same time, most young victims are in good health before the accident. World Health Organization studies indicate that in 2020 road accidents will be one of three of the three leading causes of death globally. Materials and Methods: Due to selecting the inner-city route, this study identified the accident hot zones by the number-accident intensity index method in one year. The table of coefficients proposed by the state of Georgia was used to weigh the severity of the accidents (injuries, deaths, and damages). Results: In this study, six spatial units were identified as hot zones ( 9/1% ), and 19 spatial units were identified as yellow zones ( 28/8% ); as. Finally, 41 spatial units ( 4100 meters from 6600 meters ) were identified as cold zones ( 62/1% ). Conclusion: The most important ways to reduce traffic accidents include the review of traffic signs in terms of the number, size, location, height, and the installation of the speed breaker in the spatial units as hot zones, the construction of an underpass, and the structure of pedestrian bridges with embedding the escalator in some important routs ( hot zones ), developing a comprehensive and long– term training program for improving the driving culture, etc.

Study of antioxidant activity and some herbal compounds of Dracocephalum kotschyi Boiss. in different ages of growth

•

Dracocephalum kotschyi Boiss belongs to Lamiaceae and one of the eight species of the genus Dracocephalum, is an endemic species of Iran and is grown in areas such as Isfahan, Yasuj, Mazandaran, and Tabriz. D kotschyi (Zarringiah) using the IUCN grouping criteria is one of the vulnerable species in Iran.

•

The lowest concentration of plant sample (15.8489 ± 0.001 μg/ml) was related to flower organs in the second year of cultivation, an increase can be observed in the antioxidant activity of this plant compared to the synthetic antioxidant (19.95 μg/ml).

•

The six-year-old plant with the highest antioxidant capacity, phenolic, and flavonoid compounds to produce the best age vegetative antioxidant and is mainly based on flower organs are preferred.

Objective

Dracocephalum kotschyi Boiss is one of eight species of Dracocephalum, an endemic species of Iran, and grows in areas such as Isfahan, Yasuj, Mazandaran, and Tabriz. The present study was designed to analyze the antioxidant, phenol and flavonoids contents of this plant under different conditions of cultivation in a completely randomized, factorial design.

Materials and methods

Shrubs of different ages (two, three, and six) in cultivated rangeland collected from three randomly plant at the end of May 2018 simultaneously with the flowering time. Antioxidant activity of methanolic extract of plant samples were evaluated with DPPH method. Total phenolic compounds and the total content of flavonoids were measured using the Folin Sioukhlu and aluminum chloride methods respectively.

Results

The result showed that there was a significant effect of planting time, plant organs and interaction of time and organ on the total antioxidant capacity and total phenol and flavonoids contents. The highest antioxidant activity, total phenol, and total flavonoid have belonged to the flower of six age plants. The highest antioxidant activity, total phenol, and total flavonoid have belonged to the flower of six age. The highest level of antioxidant activity with IC50 15.8489 ± 0.001 μg/ml belonged to the flower of the two-year-old plant, which has a stronger antioxidant activity than the BHT standard with 19.95 μg/ml.

Conclusion

But in general, it can be said that the six-year-old plant with the highest antioxidant capacity, phenolic, and flavonoid compounds is the best age and mainly flower organ is preferred.

Misinterpret of a unique clinical presentation named "Soo ul qinya" in Traditional Persian medicine with "Anemia"

In Traditional Persian medicine resources, soo ul qinya is one of the liver diseases that also named as pre-dropsy. The search for articles published suggests that the Soo ul qinya disease is equivalent to the anemia without any explanation. The aim of the present article is to verify this claim. A review study was conducted at 2018 on all 906 books and among credible texts of traditional medicine that have been registered on Noor Islamic software. Also, the term anemia in reference books was investigated. Moreover, "soo ul qinya" and "anemia" keywords were used for strategic searches in PubMed, Scopus and Since Direct, web of sciences, SID and Irandoc. After critical appraisal of books and articles, the required information was collected and these materials were contrasted accurately, they were compiled in the form of an article. Soo ul qinya is a difficulty in liver function and appearing weakness in it as liver could not doing its normal function and not producing good and desirable materials for feeding the body and Anemia refers to a low level of hemoglobin in the blood, which can be caused by very low levels of red blood cells or hemoglobin deficiency in blood cells. Etiology and signs and symptoms of soo ul qinya and anemia are sometimes similar and sometimes different but full compatibility between two diseases not found. Anemia is defined as a hemoglobin deficiency that can be caused by very low levels of red blood cells or hemoglobin deficiency in blood cells. However, soo ul qinya is defined as the inability of the liver to produce blood that deserves supplying foods to the cells of the body. There is a fundamental difference between anemia and soo ul qinya in this comparison because we know that the transfer of food components like proteins, carbohydrates, fats, and micronutrients occurs by the plasma, not by hemoglobin and soo ul qinya cannot be equivalent to anemia.

Efficient optical trapping with cylindrical vector beams

Radially and azimuthally polarized beams can create needle-like electric and magnetic fields under tight focusing conditions, respectively, and thus have been highly recommended for optical manipulation. There have been reports on the superiority of these beams over the conventional Gaussian beam for providing a larger optical force in single beam optical trap. However, serious discrepancies in their experimental results prevent one from concluding this superiority. Here, we theoretically and experimentally study the impact of different parameters - such as spherical aberration, the numerical aperture of the focusing lens, and the particles' size - on optical trapping stiffness of radially, azimuthally, and linearly polarized beams. The result of calculations based on generalized Lorenz-Mie theory, which is in good agreement with the experiment, reveals that the studied parameters determine which polarization state has the superiority for optical trapping. Our findings play a crucial role in the development of optical tweezers setups and, in particular, in biophysical applications when laser-induced heating in the optical tweezers applications is the main concern.

Deconvolution based photoacoustic reconstruction with sparsity regularization

In most photoacoustic tomography (PAT) reconstruction approaches, it is assumed that the receiving transducers have omnidirectional response and can fully surround the region of interest. These assumptions are not satisfied in practice. To deal with these limitations, we present a novel deconvolution based photoacoustic reconstruction with sparsity regularization (DPARS) technique. The DPARS algorithm is a semi-analytical reconstruction approach in which the projections of the absorber distribution derived from a deconvolution-based method are computed and used to generate a large linear system of equations. In these projections, computed over limited viewing angles, the directivity effect of the transducer is taken into account. The distribution of absorbers is computed using a sparse representation of absorber coefficients obtained from the discrete cosine transform. This sparse representation helps improve the numerical conditioning of the system of equations and reduces the computation time of the deconvolution-based approach by one order of magnitude relative to Tikhonov regularization. The algorithm has been tested in simulations, and using two-dimensional and three-dimensional experimental data obtained with a conventional ultrasound transducer. The results show that DPARS, when evaluated using contrast-to-noise ratio and root-mean-square errors, outperforms the conventional delay-and-sum (DAS) reconstruction method.

Does calcium score in great pelvic vessels predict colorectal anastomotic leakage? A prospective study of one hundred anastomoses

BACKGROUND

Anastomotic leakage is one of the most severe surgical complications following surgery. This prospective study was designed to investigate an association between the calcification in the descending aorta and its major branches using a calcium-scoring software and colorectal anastomotic leakage.

METHODS

From January 2012 to March 2013, one hundred patients underwent surgeries involving colorectal anastomosis procedures. Calcium score in descending aorta and great pelvic vessels was measured using the Syngo-CT 2006G-W software. A questionnaire was completed containing demographic and underlying risk factors suspicious to be associated with anastomotic leakage, in addition to surgical characteristics data.

RESULTS

55 males and 45 females entered the study with the mean age of 63.70±7.17 years. The average duration time of surgery was 149.30±20.24 minutes. The type of surgery was elective for 90 patients and emergency for 10 others. The mean calcium score was higher in greater arteries as in abdominal aorta and common iliac arteries in comparison to the other pelvic vessels. Comparing two groups of patients with and without anastomotic leakage, the calcium score was higher in descending aorta and all great pelvic vessels of patients with colorectal anastomotic leakage (P<0.001). One patient (1%) died due to postoperative anastomotic leakage two weeks after the surgery.

CONCLUSIONS

Atherosclerotic calcification in the descending aorta and its major branches can be considered as a risk factor in the development of colorectal anastomotic leakage. (Acta gastroenterol. belg., 2016, 79, 415-420).

CoolClot, a novel hemostatic agent for controlling life-threatening arterial bleeding

BACKGROUND:

Uncontrolled bleeding is the first leading cause of preventable death in the battlefield and the 2nd cause of mortality in civil accidents. Incompressible hemorrhage control is among the interventions that drastically increase the survival rate in wound individuals. We have previously shown that a certain mixture of bentonite and zeolite minerals can significantly decrease the bleeding in rats.

METHODS:

In this study, nine healthy hybrid dogs were selected and after induction of anesthesia with ether, either arterial puncture by a needle or arteriotomy was performed on both groin regions of the dogs. For control arteries (either the right or left femoral artery), only pressure by sterilized gauze was performed, while for the femoral arteries of the opposite side, our invented hemostatic agent, namely CoolClot, was topically used before applying the pressure. In the second stage of the study, to assess the coagulation time, blood samples were collected from 10 volunteer students.

RESULTS:

CoolClot significantly decreased the bleeding time in animals whose femoral arteries were cut or punctured. In the human phase of the study, the mean coagulation time in control blood samples was 253.4±44.1 seconds, whereas it was 149.5±50.0, 162.3±74.6 and 143.4±114.6 seconds, respectively in blood samples treated with bentonite, zeolite and CoolClot (P<0.05).

CONCLUSIONS:

As controlling bleeding after a life-threatening arterial damage is critical for increasing the chance of survival, the results obtained in this study indicate the significant efficacy of CoolClot in shortening the bleeding time. Our experiments also indicate that CoolClot can significantly reduce the clotting time in human blood samples.

Sol–gel synthesis, characterization, and optical properties of Gd3+-doped CdO sub-micron materials

Highly crystalline Gd3+-doped cadmium oxide micro-structure was synthesized by calcining the obtained precursor of a sol–gel reaction. The reaction was carried out with cadmium nitrate (Cd(NO3)2·4H2O), gadolinium oxide, and ethylene glycol (C2H6O2) reactants without any additives at 80°C for 2 h. The resulting gel was calcined at 900°C with increasing temperature rate of 15°C/min for 12 h in a furnace. As a result of heating, the organic section of the gel was removed, and the Gd3+-doped cadmium oxide micro-structure was produced. The obtained compound from the sol–gel technique possesses a cubic crystalline structure at a micro scale. XRD study indicates that the obtained Gd3+-doped CdO has a cubic phase. Also, the SEM images showed that the resulting material is composed of particles with cluster structure. Also, FT-IR spectroscopy was employed to characterize the Gd3+-doped CdO micro-structures.

Hydrothermal synthesis and characterization of straw bundle-like lithium sodium disilicate (silinaite) micro-rods

Highly mono-shaped straw bundle-like silinaite micro-rods have been synthesized using an aqueous mixture of silicic acid, lithium sulfate, and sodium hydroxide under hydrothermal conditions at 180°C. The synthesized materials were characterized by powder X-ray diffraction technique and Fourier transform infrared spectroscopy. The morphologies of the synthesized materials were studied by field emission scanning electron microscopy technique. The synthesized micro-rods are composed of long, fine nanosheets. Electronic absorption and photoluminescence spectra of the synthesized materials were also studied. With increasing reaction time, a blueshift was observed in the UV–vis electronic absorption and emission spectra of the synthesized materials.

Corrosion behavior of pulse electrodeposited nanostructure Ni-SiC composite coatings

Ni-SiC nano-composite coatings with various contents of SiC were prepared by pulse electrodeposition from a modified Watts bath containing SiC nano-particles. The effect of SiC concentration, current density, duty cycle and pulse frequency on the corrosion behavior of the coatings was investigated by means of potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) methods. It has been found that the Ni-SiC composite coatings show better corrosion resistance in a 3.5% NaCI solution than pure nickel. The corrosion resistance of the coatings increases by increasing the amount of embedded SiC particles. This improvement can be attributed to the morphology and the crystallographic texture of the coatings.

Functional characterization of ribosomal protein L15 from Saccharomyces cerevisiae

In this study we provide general information on the little studied eukaryotic ribosomal protein rpL15. Saccharomyces cerevisiae has two genes, YRPL15A and YRPL15B that could potentially code for yeast rpL15 (YrpL15). YRPL15A is essential while YRPL15B is dispensable. However, a plasmid-borne copy of the YRPL15B gene, controlled by the GAL1 promoter or by the promoter controlling expression of the YRPL15A gene, can functionally complement YrpL15A in yeast cells, while the same gene controlled by the authentic promoter is inactive. Analysis of the levels of YrpL15B-mRNA in yeast cells shows that the YRPL15B gene is inactive in transcription. The function of YrpL15A is highly resilient to single and multiple amino acid substitutions. In addition, minor deletions from both the N- and C-terminal ends of YrpL15A has no effect on protein function, while addition of a C-terminal tag that could be used for detection of plasmid-encoded YrpL15A is detrimental to protein function. YrpL15A could also be replaced by the homologous protein from Arabidopsis thaliana despite almost 30% differences in the amino acid sequence, while the more closely related protein from Schizosaccharomyces pombe was inactive. The lack of function was not caused by a failure of the protein to enter the yeast nucleus.

DXRaySMCS: a user-friendly interface developed for prediction of diagnostic radiology X-ray spectra produced by Monte Carlo (MCNP-4C) simulation

In this work, the general purpose Monte Carlo N-particle radiation transport computer code (MCNP-4C) was used for the simulation of X-ray spectra in diagnostic radiology. The electron's path in the target was followed until its energy was reduced to 10 keV. A user-friendly interface named 'diagnostic X-ray spectra by Monte Carlo simulation (DXRaySMCS)' was developed to facilitate the application of MCNP-4C code for diagnostic radiology spectrum prediction. The program provides a user-friendly interface for: (i) modifying the MCNP input file, (ii) launching the MCNP program to simulate electron and photon transport and (iii) processing the MCNP output file to yield a summary of the results (relative photon number per energy bin). In this article, the development and characteristics of DXRaySMCS are outlined. As part of the validation process, output spectra for 46 diagnostic radiology system settings produced by DXRaySMCS were compared with the corresponding IPEM78. Generally, there is a good agreement between the two sets of spectra. No statistically significant differences have been observed between IPEM78 reported spectra and the simulated spectra generated in this study.

Amino acids Thr56 and Thr58 are not essential for elongation factor 2 function in yeast

Yeast elongation factor 2 is an essential protein that contains two highly conserved threonine residues, T56 and T58, that could potentially be phosphorylated by the Rck2 kinase in response to environmental stress. The importance of residues T56 and T58 for elongation factor 2 function in yeast was studied using site directed mutagenesis and functional complementation. Mutations T56D, T56G, T56K, T56N and T56V resulted in nonfunctional elongation factor 2 whereas mutated factor carrying point mutations T56M, T56C, T56S, T58S and T58V was functional. Expression of mutants T56C, T56S and T58S was associated with reduced growth rate. The double mutants T56M/T58W and T56M/T58V were also functional but the latter mutant caused increased cell death and considerably reduced growth rate. The results suggest that the physiological role of T56 and T58 as phosphorylation targets is of little importance in yeast under standard growth conditions. Yeast cells expressing mutants T56C and T56S were less able to cope with environmental stress induced by increased growth temperatures. Similarly, cells expressing mutants T56M and T56M/T58W were less capable of adapting to increased osmolarity whereas cells expressing mutant T58V behaved normally. All mutants tested were retained their ability to bind to ribosomes in vivo. However, mutants T56D, T56G and T56K were under-represented on the ribosome, suggesting that these nonfunctional forms of elongation factor 2 were less capable of competing with wild-type elongation factor 2 in ribosome binding. The presence of nonfunctional but ribosome binding forms of elongation factor 2 did not affect the growth rate of yeast cells also expressing wild-type elongation factor 2.

Progression of metastatic human prostate cancer to androgen independence in immunodeficient SCID mice

Prostate cancer mortality results from metastasis to bone and hormone-independent tumor growth. Models to study these progressive changes are lacking. Here we describe the propagation of advanced human prostate cancer by direct transfer of surgical samples from patients into immune-deficient male SCID mice. Explants from six of eight patients formed prostate tumors and two showed unique cytogenetic, biologic and molecular features that were retained through six or more passages. One grew in an androgen-independent fashion, whereas the second formed tumors that regressed following castration then regrew. Micrometastatic disease was detected in the hematopoietic tissues of half of the recipient mice. Thus selected specimens of advanced human prostate cancer can be propagated in SCID mice in a manner that recapitulates the clinical transition from androgen-sensitive to androgen-independent growth, accompanied by micrometastasis.