Copper corrosion prevention in 3.5% NaCl solution by Spartium junceum petals extract as an eco-friendly bio-inhibitor: kinetic and thermodynamic studies

During the last decades, numerous studies were performed to introduce green corrosion inhibitors. So, various materials were utilized due to their being bio-degradable, available, and inexpensive. Because of the aforementioned aspects, Spartium Junceum petals extract (SJPE) was used as a new bio-inhibitor for the prevention of copper corrosion in a 3.5 wt% NaCl solution. This extract was obtained in water as a non-toxic solvent. Also, gas chromatography-mass spectrometry (GC-MS) confirmed the presence of organic molecules containing O, N, and F heteroatoms in SJPE, which are important for inhibitors. Also, Fourier-transform infrared spectroscopy (FT-IR) was used to identify the functional groups of the inhibitor molecules. Moreover, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques were used which verified the great effect of this procedure to promote resistance corrosion of copper substrate. In addition, scanning electron microscopy (SEM) exhibited the surface morphology of copper substrate in the presence of SJPE which demonstrated the improvement of corrosion resistance in comparison to the absence of this bio-inhibitor. It should be noted that by increasing the amount of SJPE, the inhibition efficiency was ameliorated up to 87.8%. Furthermore, variation in temperature magnitude between 298 and 338 K implied that SPJE can improve inhibition behavior in higher temperatures. By applying temperature effect study data, the value of activation energy in the presence of the inhibitor was calculated (37.9 kJ mol-1), and the adsorption isotherm was Langmuir. Also, these data showed the inhibition mechanism is physical adsorption. The proposed inhibitor can be used as an efficient, eco-friendly, and inexpensive bio-inhibitor for the prevention of copper corrosion.

Detection performance of pixelated lutetium-yttrium oxyorthosilicate (LYSO) scintillators for high-resolution photon-counting CT imaging

High-resolution photon-counting detector (PCD) computed tomography (CT) imaging is increasingly used for several applications. Recent technological advances in CT instrumentation have introduced various types of radiation detectors. Therefore, this work aims at evaluating the lutetium-yttrium oxyorthosilicate (LYSO) scintillator for use in PCD CT from a detector point of view. To do so, a mini-CT prototype was designed and constructed based on the pixelated LYSO blocks. The detector comprises four 10 × 10 linearly arranged LYSO blocks coupled with four position-sensitive photomultiplier tubes. The prototype utilizes a point gamma-ray source along with a cone-beam collimator. An in-home MATLAB-based data processing software package was also developed for storing the list-mode data, event positioning, and energy windowing. A set of experiments were conducted to assess the performance of the constructed energy-resolved LYSO:Ce detector for mini-CT imaging. The results show good crystal identification for all blocks with a maximum peak-to-valley ratio of 3.48. In addition, the findings confirm that the developed detector is position-sensitive. The 20% energy window provides an optimal performance by simultaneously providing good crystal identification and a scatter removal factor of 0.71. A 96% uniformity was also observed when the detector was irradiated with a uniform flood. The spatial resolution of the mini-CT prototype in the x- and y-directions was calculated to be 0.9 and 0.93 mm, respectively, corrected for a magnification factor of 2.5. It is concluded that the pixelated LYSO crystal is a promising alternative to the current detectors and would be the scintillator of choice for high-resolution PCD CT imaging tasks.

Detecting and tracking multiple mobile radioactive sources by data fusion of a surveillance camera and a sodium iodide (NaI) detector

Nowadays, the use of radioactive materials has increased due to recent progress in nuclear technology, but concerns about the missing or smuggling of radioactive materials have persisted. Nuclear threats such as terrorist attacks or the malicious use of radioactive materials out of regulatory control (MORC) are always severe problems that can result in adverse environmental, health, economic, and security effects. Applying new technologies to monitor and track MORC will prevent radioactive materials from being illegally transported across borders or from one place to another. In this research, we have constructed a detection system to automatically and remotely localize multiple mobile gamma-emitting radiation sources among other objects by combining an IP camera and a sodium iodide detector. An algorithm for the detection system has been developed to identify the objects' paths from camera data and correlate radiation data with the paths to detect contaminated objects. We evaluated the system using two weak radioactive sources (Co-60, Cs-137), which were hidden on moving objects, and succeeded in finding harmful targets. The results have also shown that by increasing the number of contaminated sources from one to two, the detection accuracy decreases by about 2.5 times. However, by doubling the speed of mobile targets, the detection accuracy improved by about 30%. Detecting and tracking MORC with a single detection system is limited to small regions. By equipping many surveillance cameras in a city with relatively inexpensive radioactive detectors, a network sensing system is established to find radioactive hotspots in a smart city.

An intelligent gamma-ray technique for determining wax thickness in pipelines

Measuring the wax deposition inside pipelines is one of the critical parameters in the oil, gas and petrochemical industries to control the flow through the pipelines. This paper presents a novel method using artificial neural networks to measure the thickness of the wax. This method was based on counting the backscattered gamma-ray from different thicknesses of the wax inside the pipes with different diameters. For this purpose, the system was simulated by MCNPX code and the designed setup was optimized. The main analyses were based on the simulation results but the verification was performed using a real experimental setup. The results showed a good agreement between the simulation results and the experimental data with a root mean square error less than 1%. Response of the detector was simulated for a standard industrial nominal pipe ranged from 2 to 4.5 inches and for radiation sources ¹³⁷Cs and ⁶⁰Co. Using these data, a multilayer perceptron for different energy sources was trained. The best prediction of the wax thickness was obtained for the case of using two radiation sources, simultaneously. The output of the trained neural network showed that the proposed method is capable of measuring the wax thickness inside the pipe with a good accuracy.

Perceived effectiveness of clinical pathway software: A before-after study in the Netherlands

BACKGROUND

Clinical pathways (CPs) increase in popularity and are known to lead to several benefits in the hospital environment. Clinical pathways can be either paper-based or software-based. It is known that paper-based CPs can result in more paperwork instead of simplifying daily routines of healthcare workers. Insufficient research has been done on the acceptance of software-based CPs by different user groups. Our aim in this study was to assess the effectiveness of the software-based CPs (CPS) from the perspective of healthcare professionals in the hospital environment as well as to investigate the differences in perceived effectiveness between user groups.

METHODS

Using surveys and interviews, data were collected in four departments of an academic medical center. A distinction was made between decision makers (DM) and executive staff (ES). The surveys contained questions based on the Technology Acceptance Model and four objectives of the software defined by the hospital. Statistical tests were used to investigate the effectiveness of CPS and study the differences between DM and ES. Interviews were recorded and transcribed based on grounded theory principals.

RESULTS

After implementation, monitoring protocol-based working was significantly improved (p = .026) and significantly higher efficiency on the work floor was reported (p = .046). ES perceived the software as less useful than expected (Md = 3.25 vs. Md = 2.75, p = .028) compared to DM and were less convinced of its ability to improve monitoring protocol-based working. The most important benefits of CPS as perceived by its users are the better overview of tasks it provides and facilitating documentation. Negative aspects mentioned were the lack of usability and the inflexibility of the software, and particularly ES claimed that the software did not increase their effectiveness.

CONCLUSION

Our study showed that CPS is effective from healthcare professionals' perspective due to its ability to increase monitoring of protocol-based working and by enhancing the efficiency on the work floor. However, the users also acknowledge that the software lacks usability and is not flexible enough, which results in an additional workload. Policy makers should be more focused on informing and training executive staff more thoroughly when implementing a CPS. Our results strongly suggest that executive staff members need to be convinced of its usefulness and the added value a CPS provides. Preferably, they should be involved in the design phase of the software.

A gamma-ray tomography system to determine wax deposition distribution in oil pipelines

Monitoring wax deposition in pipelines is of particular importance for oil extraction companies. In this work, a new gamma-ray tomography system based on using a rod CsI(Na) scintillator and ¹³⁷Cs gamma source was developed to view the cross section of oil pipelines. The system can estimate the interaction position of gamma-rays by measuring light attenuation in the rod scintillator using two photomultiplier tubes coupled to its ends. Therefore, despite the simple structure of the employed detector, it can act as a position-sensitive instrument. In order to test the proposed tomography system, a selection of desired polyethylene round-bar pieces (as different wax thicknesses) was prepared to be placed in iron pipes, and their projections at different angles were acquired to construct cross-sectional images as well. The results showed that the designed system had the ability to scan the interior of the pipes and determine wax thickness with an error between 2.4% and 11.4%.

Pros and Cons of Clinical Pathway Software Management: A Qualitative Study

In this study we aimed to assess the perceived effectiveness of clinical pathway management software for healthcare professionals. A case study on the clinical pathway management software program Check-It was performed in three departments at an academic medical center. Four months after the implementation of the software, interviews were held with healthcare professionals who work with the system. The interview questions were posed in a semi-structured interview format and the participant were asked about the perceived positive or negative effects of Check-It, and whether they thought the software is effective for them. The interviews were recorded and transcribed based on grounded theory, using different coding techniques. Our results showed fewer overlooked tasks, pre-filled orders and letters, better overview, and increased protocol insight as positive aspects of using the software. Being not flexible enough was experienced as a negative aspect.

Aberrant promoter hypermethylation of selected apoptotic genes in childhood acute lymphoblastic leukemia among North Indian population

Promoter hypermethylation mediates gene silencing in many neoplasms. Acute leukemia has been reported to harbor multiple genes aberrantly silenced by hypermethylation.

AIM

In present study, we investigated the prevalence of hypermethylation of caspase-8 (CASP8), TMS1 and DAPK genes in correlation with clinicopathological factors in childhood acute lymphoblastic leukemia (ALL).

MATERIALS AND METHODS

A case-control study has been conducted based on bone marrow and peripheral blood samples from 125 ALL patients and 100 sex-age matched healthy controls. Methylation specific polymerase chain reaction (PCR) and bisulfite sequencing PCR was performed to analyze the methylation status of these genes. Reverse transcription PCR and real time PCR was carried out to determine changes in the mRNA expression level of the genes due to hypermethylation.

RESULTS

Hypermethylation of the 5´CpG islands of the CASP8, TMS1 and DAPK gene promoters was found in 3.2, 6.4, and 13.6% of 125 childhood ALL samples from north Indian population, respectively. There were significant differences in pattern of hypermethylation of TMS1 (p = 0.045) and DAPK (p < 0.001) between patients and healthy controls. Down-regulation of mRNA expression was found in cases in which CASP8, TMS1 and DAPK were hypermethylated.

CONCLUSIONS

The present study indicated the impact of hypermethylation-mediated inactivation of CASP8, TMS1 and DAPK genes, which is associated with risk of childhood ALL. This abnormality occurs in leukemogenesis and it may be used as a biomarker and for predicting the prognosis of ALL.

Assessment of the quality of fall detection and management in primary care in the Netherlands based on the ACOVE quality indicators

We determined adherence to nine fall-related ACOVE quality indicators to investigate the quality of management of falls in the elderly population by general practitioners in the Netherlands. Our findings demonstrate overall low adherence to these indicators, possibly indicating insufficiency in the quality of fall management. Most indicators showed a positive association between increased risk for functional decline and adherence, four of which with statistical significance.

INTRODUCTION

This study aims to investigate the quality of detection and management of falls in the elderly population by general practitioners in the Netherlands, using the Assessing Care of Vulnerable Elders (ACOVE) quality indicators.

METHODS

Community-dwelling persons aged 70 years or above, registered in participating general practices, were asked to fill in a questionnaire designed to determine general practitioner (GP) adherence to fall-related indicators. We used logistic regression to estimate the association between increased risk for functional decline-quantified by the Identification of Seniors At Risk for Primary Care score-and adherence. We then cross-validated the self-reported falls with medical records.

RESULTS

Of the 950 elders responding to our questionnaire, only 10.6 % reported that their GP proactively asked them about falls. Of the 160 patients who reported two or more falls, or one fall for which they visited the GP, only 23.1 % had fall documentation in their records. Adherence ranged between 13.6 and 48.6 %. There was a significant positive association between the ISAR-PC scores and adherence in four QIs. Documentation of falls was highest (36.7 %) in patients whom the GP had proactively asked about falls.

CONCLUSION

Based on patient self-reports, adherence to the ACOVE fall-related indicators was poor, suggesting that the quality of evaluation and management of falls in community-dwelling older persons in the Netherlands is poor. The documentation of falls and fall-related risk factors was also poor. However, for most QIs, adherence to them increased with the increase in the risk of functional decline.

Tissue fatty acid composition and secretory phospholipase-A2 activity in oral squamous cell carcinoma

PURPOSE

Oral squamous cell carcinoma (OSCC) is a remarkable health problem worldwide, but its pathogenesis remains unknown. The aim of this study was to compare fat composition and secretory phospholipase-A2 (sPLA2) activity between the malignant and adjacent normal squamous tissues in patients with OSCC.

METHODS

Paired samples of malignant squamous and adjacent normal-appearing tissues were collected from 27 patients with OSCC. The fatty acid composition in the obtained tissues was determined by gas liquid chromatography. Tissue enzyme activities of sPLA2 were measured using the standard assay with Diheptanoyl Thio-Phosphatidylcholine as substrate.

RESULTS

In the OSCC tissue, the level of stearic acid (18:0) and activity of sPLA2 were higher (P < 0.001), and the levels of oleic acid (18:1n-9) and linoleic acid (18:2n-6) were lower than that in the adjacent normal-appearing squamous tissue (P < 0.001). The activity of sPLA2 in OSCC was strongly negatively correlated with the amount of 18:2n-6 (r = -0.41, P < 0.001). Negative significant associations were observed between the OSCC invasion and tissue levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHE).

CONCLUSION

The changes in the fatty acid composition and sPLA2 activity may be regarded as indicators of altered lipid metabolism occurring in vivo during squamous cell carcinogenesis.

The -137G/C polymorphism of interleukin 18 promoter and risk of HIV-1 infection and its progression to AIDS

A growing body of evidence suggests that host genetic factors play an important role both in susceptibility to human immunodeficiency virus 1 (HIV-1) infection and in progression to AIDS. Interleukin 18 (IL-18) is a pleiotropic proinflammatory cytokine that serves as an important regulator of immune responses. It plays a key role in induction of both Th1 and Th2 cytokines and, thereby, modulates their immune responses. Single nucleotide polymorphisms in the IL-18 gene promoter region may lead to an altered transcriptional activity and IL-18 production, and so this may account for individuals' variation to the risk of HIV-1 infection. With this perspective, the -137G/C polymorphism in the promoter region of the IL-18 gene was studied in 500 patients with HIV-1/AIDS and an equal number of sex and age matched healthy controls using sequence specific polymerase chain reaction analysis. We did not observe any significant association of the heterozygous G/C genotype with the risk of HIV-1-infection/AIDS. However, statistically significant associations of the G allele and homozygous G/G genotype of -137 G/C polymorphism of IL-18 promoter with increased risk of HIV-1/AIDS were identified. The data of the present study suggest that IL-18 -137 G allele and G/G genotype seem to be involved in the pathogenesis of HIV-1 infection among North Indians.

Polymorphisms of MTHFR and MTR genes are not related to susceptibility to childhood ALL in North India

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most worldwide common type of childhood cancer. Methylenetetrahydrofolate reductase (MTHFR) and 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) participate in folate pathways and are known as critical factors for DNA integrity as well as DNA hypomethylation. The aim of this work is to investigate frequency of MTHFR (677C→T and 1298A→C) and MTR (2756A→G) polymorphisms and their interaction with respect to possible effect on risk of childhood ALL among North Indian population.

PROCEDURE

A case control study from has been conducted on bone marrow and peripheral blood samples from 125 ALL patients and 100 sex-age matched healthy controls using PCR-RFLP method.

RESULTS

No statistically significant differences were observed for different genotypes between patients and controls (p>0.05). Significant difference for the risk of ALL in individuals having genotype of MTHFR 677TT (OR=0.61, 95% CI=0.21-1.77) and MTHFR 1298CC (OR=0.56, 95% CI=0.18-1.68) was not observed. The correlation of SNP of MTR gene and risk of ALL was not observed, too.

CONCLUSIONS

The differences in distribution of possible combined genotypes of MTHFR (677C→T, 1298A→C) and MTR (2756A→G) between ALL patients and controls were statistically insignificant.

A closed form for the electrostatic interaction between two rod-like charged objects

We have calculated the electrostatic interaction between two rod-like charged objects with arbitrary orientations in three dimensions. We obtained a closed-form formula expressing the interaction energy in terms of the separation distance between the centers of the two rod-like objects, r, their lengths (denoted by 2l₁ and 2l₂) and their relative orientations (indicated by θ and φ). When the objects have the same length (2l₁ = 2l₂ = l), for particular values of separations, i.e. for r ≤ 0.8l, two types of minimum appear in the interaction energy with respect to θ. By employing the closed-form formula and introducing a scaled temperature t, we have also studied the thermodynamic properties of a 1D system of rod-like charged objects. For different separation distances, the dependence of the specific heat of the system to the scaled temperature has been studied. It is found that, for r < 0.8l, the specific heat has a maximum.

Microarray sampling-platform fabrication using bubble-jet technology for a biochip system

The fabrication of microarrays containing PCR-amplified genomic DNA extracts from mice tumors on a Zetaprobe membrane using a modified thermal ink-jet printer is described. A simple and cost-effective procedure for the fabrication of microarrays containing biological samples using a modified bubble-jet printing system is presented. Because of their mass-produced design, ink-jet printers are a much cheaper alternative to conventional spotting techniques. The usefulness of the biochip microarray platform is illustrated by the detection of human fragile histidine triad (FHIT), a tumor suppressor gene. Subcutaneous carcinomas were induced with MKN/FHIT and MKN/E4 cell lines in immunodeficient mice. Several weeks into their development, the tumors from both groups of mice were removed and subjected to DNA extraction by lysis of tissue samples. The extracted DNA samples were amplified by PCR (30 cycles) using the primers corresponding to nucleotides 2 to 18 of the FHIT sequence. The resulting solution was transferred to the individual reservoirs of a three-color cartridge from a conventional thermal ink-jet printer (HP 694C), and arrays were printed on to a Zetaprobe membrane. After spotting, these membranes were used in a hybridization assay, using fluorescent probes, and detected with a biochip.

Application of an antibody biochip for p53 detection and cancer diagnosis

Detection of the p53 tumor suppressor gene is important in early cancer diagnostics because alterations in the gene have been associated with carcinogenic manifestations in several tissue types in humans. We have developed an antibody-based detection instrument, the biochip, to detect the presence of the anti-p53 antibody in human serum. The design of this highly integrated detector system is based on miniaturized phototransistors having multiple optical sensing elements, amplifiers, discriminators, and logic circuitry on an IC board. The system utilizes laser excitation and fluorescence signals to detect complex formation between the p53 monoclonal antibody and the p53 antigen. Recognition antibodies are immobilized on a nylon membrane platform and incubated in solutions containing antigens labeled with Cy5, a fluorescent cyanine dye. Subsequently, this membrane is placed on the detection platform of the biochip and fluorescence signal is induced using a 632.8-nm He-Ne laser. Using this immuno-biochip, we have been able to detect binding of the p53 monoclonal antibody to the human p53 cancer protein in biological matrices. The performance of the integrated phototransistors and amplifier circuits of the biochip, previously evaluated through measurement of the signal output response for various concentrations of fluorescein-labeled molecules, have illustrated the linearity of the microchip necessary for quantitative analysis. The design of this biochip permits sensitive, selective and direct measurements of a variety of antigen-antibody formations at very low concentrations. Furthermore, the acquisitions of the qualitative and quantitative results are accomplished rapidly, in about 15 min. These features demonstrate the potential of this antibody-based biochip for simple, rapid and early biomedical diagnostics of cancer.

Estrogenic and DNA-damaging activity of Red No. 3 in human breast cancer cells

Exposure to pesticides, dyes, and pollutants that mimic the growth promoting effects of estrogen may cause breast cancer. The pesticide DDT and the food colorant Red No. 3 were found to increase the growth of HTB 133 but not estrogen receptor (ER) negative human breast cells (HTB 125) or rat liver epithelial cells (RLE). Red No. 3, beta-estradiol, and DDT increase ER site-specific DNA binding to the estrogen response element in HTB 133 cells and increase cyclin-dependent kinase 2 activity in MCF-7 breast cancer cells. Site-specific DNA binding by p53 in RLE, HTB 125, HTB 133, and MCF-7 cells was increased when they were treated with Red No. 3, which suggests that cellular DNA was damaged by this colorant. Red No. 3 increased binding of the ER from MCF-7 cells to the estrogen-responsive element. Consumption of Red No. 3, which has estrogenlike growth stimulatory properties and may be genotoxic, could be a significant risk factor in human breast carcinogenesis.

DDT mimicks estradiol stimulation of breast cancer cells to enter the cell cycle

Estrogens play a critical role in the etiology of found breast cancer. Estradiol promotes the growth of breast cancer cells in vivo and in vitro. Exogenous estrogens in both the environment and in the human diet increase the growth of breast cancer cells in vitro. A role for xenoestrogens in breast cancer etiology has been proposed but remains controversial. We examined the effects of the xenoestrogenic pesticide 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (DDT) on estrogen-receptor (ER)-positive MCF-7 and T-47D human breast cancer cells as well as on ER-negative HS 578Bst breast cancer cells and rat liver cells. Estradiol and DDT were found to increase the growth of MCF-7 cells in the presence of insulin. The activity of cyclin-dependent kinase (Cdk)2 increased in growth-arrested T-47D and MCF-7 cells treated with beta-estradiol or DDT. The steroidal antiestrogen ICI 182,780 prevented both growth and Cdk2 activation induced by estradiol or DDT. Increased phosphorylation of Cdk2 and the retinoblastoma protein (pRb1O5) was observed in ER-positive cells treated with DDT or estradiol. Cdk2 activity was not affected by DDT or estradiol in ER-negative HS 578Bst breast cancer cells or in rat liver epithelial cells. Cyclin D1 protein synthesis was increased by DDT and estradiol in MCF-7 cells. DDT and estradiol-induced ER-dependent transcriptional activation of estrogen response elements (EREs) in stably transfected MVLN cells, and ERE activation by low doses of DDT was increased by insulin. These findings suggest that DDT can stimulate breast cancer cells to enter into the cell cycle by directly affecting key regulatory elements. The relative potency of DDT in inducing cell-cycle progression appears to be only 100-300 times less than that of estradiol when measured in the presence of insulin. Therefore, the cancer risks associated with DDT exposure may be greater than first thought, especially when additional mitogenic stimuli are present.

Carcinogenic potential of benzene and toluene when evaluated using cyclin-dependent kinase activation and p53-DNA binding

Benzene is carcinogenic, whereas toluene is thought to have little carcinogenic potential. Benzene and toluene were found to activate cyclin-dependent kinase 2 in rat liver epithelial (RLE) and HL60 cells. pRb105 was hyperphosphorylated in RLE cells treated with either solvent. Kinase activation and subsequent hyperphosphorylation of pRb105 and p53 by benzene or toluene may be responsible for their growth promotional effects, but it does not account for increased potential of benzene to induce cancer. Therefore, we examined the ability of these solvents to increase p53-DNA site-specific binding in RLE cells. Benzene increased p53-DNA site-specific DNA binding in RLE cells compared to control levels or the effects of toluene. Increased p53-DNA site-specific binding by benzene may be caused by damage to cellular DNA. If so, although both solvents appear to have promotional activity, the increased potential of benzene to damage DNA may be responsible to the difference in the ability of benzene to cause cancer.

Transforming growth factor-beta 1 as a signal for induction of cell death by apoptosis

Cell death by apoptosis is a major determinant of growth of normal tissues and tumours. The present study aimed to elucidate signal factors involved in its regulation. Epithelial cells in control liver, during regression of cyproterone acetate induced liver hyperplasia, in liver (pre)neoplasia and in uterus undergoing apoptosis in vivo show immunostaining for transforming growth factor beta 1 (TGF-beta 1) as detected by anti-pre(266-278) TGF-beta 1 antibodies. Positive immunostaining is also seen in a few intact cells of hyperplastic, regressing liver apparently preparing for apoptosis, but is virtually not found in hepatocytes of normal or growing liver nor in cells undergoing death by necrosis. Recombinant latency associated protein (rLAP, dimer of the pro-region non-covalently associated with the mature region) complex and mature TGF-beta 1 induce apoptosis in isolated hepatocytes cultured in vitro. These findings suggest an involvement of TGF-beta 1 in the induction of apoptosis in certain epithelia in vivo.

Characterization of a complex chromosomal rearrangement maps the locus for in vitro complementation of xeroderma pigmentosum group D to human chromosome band 19q13

Microcell-mediated chromosome transfer (MMCT) is a powerful genetic technique that permits the transfer of a single chromosome from one mammalian cell to another. The utility of MMCT for gene mapping strategies is critically dependent on the careful characterization of the chromosomes being transferred. We have recently reported the identification of a single rearranged human chromosome, designated Tneo, which corrects the UV sensitivity and excision repair defect of cells of xeroderma pigmentosum genetic complementation group D (XP-D) in culture (Flejter WL et al., Proc Natl Acad Sci USA 89:261-265, 1992). Additionally, those studies demonstrated a role for the excision repair cross-complementing 2 (ERCC2) gene in the observed phenotypic correction. We now report the results of detailed conventional and molecular cytogenetic characterization of the complementing Tneo chromosome. This analysis revealed a complex rearrangement involving material from human chromosomes 16, 17, and 19. Characterization of deletions of Tneo which retained or lost XP-D complementing ability mapped the gene responsible for phenotypic correction to a small region of the terminal q-arm of this chromosome. This region includes the previously described human DNA repair gene cluster located in the region 19q13.2-q13.3, a result consistent with the notion that the in vitro correction of XP-D cells by the Tneo chromosome is rendered by the ERCC2 locus. The data illustrate the potential value of detailed cytogenetic characterization of a human chromosome present in a somatic cell hybrid, even when that material involves complex rearrangements.

Effects of sympathetic innervation on size of myocytes in embryonic rat heart cultured in oculo

Embryonic rat myocardium cultured in the anterior eye chamber of an adult rat increases in mass and differentiates into mature myocardium by most morphological criteria [1]. When sympathetic innervation of grafted heart tissue was prevented by superior cervical ganglionectomy (SCGx), growth of the grafts was severely compromised. The present study used morphometric methods to examine the contribution of myocyte size to the differential growth of grafts in sympathetically denervated and intact eye chambers. For this purpose, atria or ventricles from 12-day gestation rat hearts were grafted into sympathetically denervated and intact eye chambers of male host rats. Tissue was harvested after either 2 or 8 weeks in oculo. Myocyte diameter and the ratio of cytoplasmic area to nuclear area increased between 2 and 8 weeks in oculo in both atrial and ventricular grafts. In these unloaded heart grafts, estimated myocyte size did not differ between atrial and ventricular myocytes. Grafts into sympathetically innervated and denervated eye chambers did not differ in myocyte diameter or in the ratio of cytoplasmic to nuclear area, suggesting that myocyte size cannot explain the smaller mass of grafts in sympathetically denervated eye chambers. Thus, it is likely that other factors such as myocyte proliferation, myocyte survival or altered tissue composition underlie the lesser growth of grafts not innervated by sympathetic nerves.

Induction of dermal and subcutaneous inflammation by recombinant cachectin/tumor necrosis factor (TNF alpha) in the mouse

The ability of cachectin/tumor necrosis factor (TNF alpha) to induce acute dermal and subcutaneous inflammation was examined in a murine model. A number of other proteins, and diluent alone were examined as controls. After subcutaneous injection into the mouse footpad, recombinant human TNF alpha (rHuTNF alpha) induced acute inflammation with an initial marked dermal and subcutaneous neutrophil infiltrate by approximately 3 h, with a peak between 4 and 24 h and resolution by 79 h. Recombinant interleukin-2, cytochrome c, and heat-inactivated rHuTNF alpha induced negligible inflammation. Recombinant human lymphotoxin (TNF beta), another control protein, also induced acute inflammation in our system. Because TNF alpha and TFN beta are partially homologous, they may be acting through a similar mechanism. This pro-inflammatory effect of TNF alpha may result from chemotactic activity as well as by induction of secondary mediators. Inflammation induced by TNF alpha was partially suppressed by indomethacin treatment, suggesting that products of the cyclo-oxyganase pathway may mediate a portion of the inflammation involved. Five daily injections of rHuTNF alpha into the mouse footpad resulted in a predominantly mononuclear infiltrate and focal fibrosis. These results suggest that TNF alpha may be an important mediator of acute inflammation in vivo and might provide a signal for the production of collagen.

Epidermal cells in activation of suppressor lymphocytes: further characterization

Intravenous administration of hapten-coupled, high-density (density greater than 1.077) epidermal cells (HD-EC) to mice results in the appearance of transferable splenic T suppressor (Ts) cells as assayed in adoptive transfer experiments. Depletion of I-A bearing cells from the HD-EC population before hapten coupling prevents these cells from inducing Ts cell formation, whereas depletion of Thy-1-bearing cells from the HD-EC cell preparation has no effect. When HD-EC are adhered to glass for 2 hr, the ability to induce Ts cell formation resides in the adherent population. Exposure of HD-EC to a dose of ultraviolet radiation (UVR) that largely abrogates the ability of hapten-coupled EC to immunize mice for a DTH response does not affect the ability of these cells to activate Ts cells. Treatment of mice with i.p. administration of 20 mg/kg of cyclophosphamide 2 days before EC harvesting abrogates the ability of HD-EC from these mice to induce Ts cell formation. HD-EC from B10.A(3R) (I-Jb) but not B10.A(5R) (I-Jk) mice induce Ts cell formation in B10.A(3R) mice, demonstrating that the ability to do so is restricted by the I-J locus. Transmission electron microscopy of adherent HD-EC populations demonstrated that two cell types were present. One type had the characteristics of keratinocytes; the other was monocyte-like and resembled Langerhans cells or indeterminate cells in many aspects. Immunoelectron microscopy revealed this second cell type to bear I-A/I-E antigen. These cells were T-200 positive and Mac-1 negative by immunoperoxidase staining. Extensive examination by light and electron microscopy failed to reveal any dermal components in the EC populations; however, a very small degree of dermal contamination cannot be excluded. Thus, EC that activate afferent-acting Ts cells are high-density, I-A+, Thy-1-, I-J restricted, glass adherent, and functionally UVR resistant and cyclophosphamide sensitive.

Epidermal cells in activation of suppressor lymphocytes: further characterization

Intravenous administration of hapten-coupled, high-density (density greater than 1.077) epidermal cells (HD-EC) to mice results in the appearance of transferable splenic T suppressor (Ts) cells as assayed in adoptive transfer experiments. Depletion of I-A bearing cells from the HD-EC population before hapten coupling prevents these cells from inducing Ts cell formation, whereas depletion of Thy-1-bearing cells from the HD-EC cell preparation has no effect. When HD-EC are adhered to glass for 2 hr, the ability to induce Ts cell formation resides in the adherent population. Exposure of HD-EC to a dose of ultraviolet radiation (UVR) that largely abrogates the ability of hapten-coupled EC to immunize mice for a DTH response does not affect the ability of these cells to activate Ts cells. Treatment of mice with i.p. administration of 20 mg/kg of cyclophosphamide 2 days before EC harvesting abrogates the ability of HD-EC from these mice to induce Ts cell formation. HD-EC from B10.A(3R) (I-Jb) but not B10.A(5R) (I-Jk) mice induce Ts cell formation in B10.A(3R) mice, demonstrating that the ability to do so is restricted by the I-J locus. Transmission electron microscopy of adherent HD-EC populations demonstrated that two cell types were present. One type had the characteristics of keratinocytes; the other was monocyte-like and resembled Langerhans cells or indeterminate cells in many aspects. Immunoelectron microscopy revealed this second cell type to bear I-A/I-E antigen. These cells were T-200 positive and Mac-1 negative by immunoperoxidase staining. Extensive examination by light and electron microscopy failed to reveal any dermal components in the EC populations; however, a very small degree of dermal contamination cannot be excluded. Thus, EC that activate afferent-acting Ts cells are high-density, I-A+, Thy-1-, I-J restricted, glass adherent, and functionally UVR resistant and cyclophosphamide sensitive.