ERK1/2-induced phosphorylation of R-Ras GTPases stimulates their oncogenic potential.

The Ras-related (R-Ras) isoforms TC21, R-Ras and M-Ras are members of the Ras superfamily of small GTPases. R-Ras family proteins are frequently overexpressed in human cancers, and expression of activated mutants of these GTPases is sufficient to induce cell transformation. Unlike Ras, few activating mutations of R-Ras proteins have been reported in human cancer, and very little is known about the regulation of their activity. In this study, we report that TC21 and R-Ras are phosphorylated on a conserved serine, Ser186 and Ser201, respectively, in intact cells. This residue is located in the C-terminal hypervariable region of the proteins and is not conserved in M-Ras. We show that the MAP kinases ERK1/2 phosphorylate TC21 and R-Ras on this C-terminal serine residue both in vitro and in vivo. Phosphorylation of R-Ras proteins does not affect their subcellular localization or stability but rather stimulates their activation. Phosphorylation-defective mutants of R-Ras and TC21 are compromised in their ability to promote cancer cell adhesion and migration/invasion, respectively. Importantly, we show that phosphorylation of TC21 and R-Ras potentiates their tumorigenic activity in immunodeficient mice. Our results identify a novel regulatory mechanism of the small GTPases TC21 and R-Ras that controls their oncogenic potential.

Deposition of Poly(diphenylamine-co-3-aminobenzonitrile)/Palladium Nanocomposite Film and Evaluation of Electrocatalytic Activity Toward Borohydride Oxidation.

New nanocomposites, poly(diphenylamine-co-3-aminobenzonitrile)/palladium (P(DPA-co-3ABN)/Pd) and poly(diphenylamine)/palladium (PDPA/Pd), have been prepared by pulse potentiostatic method and used as electrocatalysts for borohydride oxidation. Linear sweep voltammogram of P(DPA-co-3ABN)/Pd-ME exhibited the oxidation wave between -0.8 V and 0.4 V that corresponds to the direct, potentially four-electron, oxidation of borohydride ions. The peak current for borohydride oxidation is much higher at P(DPA-co-3ABN)/Pd-ME electrode as compared to PDPA/Pd-ME. The incorporation of 3ABN units augments electrocatalytic behavior and thermal stability for the P(DPA-co-3ABN)/Pd catalyst.

Facile electrodeposition of flower like gold nanostructures on a conducting polymer support.

Herein, we report an attractive, simple and templateless synthetic method for the formation of anisotropic gold nanostructures. Gold 'mesoflowers' consisting of arrays of nanoplatelets were synthesized by electrochemical gold deposition on/off conditions onto a conducting poly(diphenylamine) (PDPA) support matrix. A possible forming mechanism of anisotropic gold nanostructures is presented. The electronic and electrochemical properties of gold nanoflower decorated PDPA in an assembled diode configuration were evaluated.

Synthesis of novel poly(amidoxime) grafted multiwall carbon nanotube gel and uranium adsorption.

This is the first report on the synthesis of a new functional nanocomposite gel containing amidoxime functionalized multiwall carbon nanotube (AO-MWNT-FNC GEL). The surface morphology of AO-MWNT-FNC GEL was investigated by field emission scanning electron microscopy. The modification of gel with amidoxine groups was confirmed by Fourier transform infra red spectroscopy. The AO-MWNT-FNC GEL provides effective binding with uranium ions as was ascertained by X-ray photoelectron spectroscopy. The AO-MWNT-FNC GEL was utilized as the new adsorbent for the recovery of uranium ions from aqueous solution. UV-visible spectroscopy was used to monitor the adsorption capacity of the AO-MWNT-FNC GEL toward uranium ions. The influence of initial uranium ion concentration and solution pH on the adsorption capacity of the AO-MWNT-FNC GEL were studied in batch experiments. The new FNC-GEL designed in this study is distinguished by higher adsorption capacity for uranium ions due to the synergistic contributions from high surface area of MWNT and the functional AO groups in FNC-GEL and exhibits potential for efficient recovery of uranium ions.

A kinetic study on the formation of poly(4 aminodiphenylamine)/copper nanocomposite using UV-visible spectroscopy.

The course of the reaction between copper sulfate (CuSO4) and 4-aminodiphenylamine (4ADPA) was monitored by UV-visible spectroscopy in p-toluene sulfonic acid (p-TSA). Formation of poly(4-aminodiphenylamine)/copper nanoparticle composite (P4ADPA/CuNC) was witnessed through the steady increase in absorbance at 410, 580 and >700 nm. The absorbance at 410 nm as well as >700 nm are correlated to the amount of P4ADPA/CuNC formation and was subsequently used to determine the rate of formation of P4ADPA/CuNC (RP4ADPA/CuNC) at any time during the course of the reaction. RP4ADPA/CuNC shows a first-order dependence on [4ADPA] and a half-order dependence on [CuSO4]. A kinetic rate expression was established between RP4ADPA/CuNC and experimental parameters such as [4ADPA] and [CuSO4]. The rate constant for the formation of P4ADPA/CuNC was 8.98 × 10(-3) mol(-0.5) l(0.5) s(-1). Field emission scanning electron and transmission electron micrographs revealed that the morphology of the P4ADPA/CuNC was influenced by the reaction conditions.

Development of a novel cyano group containing electrochemically deposited polymer film for ultrasensitive simultaneous detection of trace level cadmium and lead.

Poly(diphenylamine-co-2-aminobenzonitrile) (P(DPA-co-2ABN)), a cyano group containing conducting polyaniline derivative, has been electrodeposited developed as the new material and utilized for the simultaneous electrochemical determination of trace levels of cadmium (Cd(2+)) and lead (Pb(2+)). P(DPA-co-2ABN) film preconcentrates effectively through cyano chelation and electrochemically strips the heavy metal ions with well separated potentials, which are beneficially utilized for ppb level simultaneous detection of Cd(2+) and Pb(2+). Differential pulse voltammetry studies revealed that Cd(2+) and Pb(2+) ions were simultaneously stripped with well-defined, separated and sharp peaks for Cd(2+) and Pb(2+). The influence of various operational parameters such as pulse amplitude, pulse time, scan rate, initial potential, end potential, accumulation potential and accumulation time on the electrochemical stripping of heavy metals were investigated in details. Under the optimal conditions, good linear correlations were obtained from 1.26 to 907.8 ppm for Cd(2+) and 0.26 to 58.73 ppm for Pb(2+), respectively. Low detection limits for Cd(2+) and Pb(2+), 0.255 ppm and 0.165 ppm, respectively, were observed. The practical utility of the new procedure was demonstrated in real samples.

A validation study of multicenter diffusion tensor imaging: reliability of fractional anisotropy and diffusivity values.

BACKGROUND AND PURPOSE: DTI is increasingly being used as a measure to study tissue damage in several neurologic diseases. Our aim was to investigate the comparability of DTI measures between different MR imaging magnets and platforms. MATERIALS AND METHODS: Two healthy volunteers underwent DTI on five 3T MR imaging scanners (3 Trios and 2 Signas) by using a matched 33 noncollinear diffusion-direction pulse sequence. Within each subject, a total of 16 white matter (corpus callosum, periventricular, and deep white matter) and gray matter (cortical and deep gray) ROIs were drawn on a single image set and then were coregistered to the other images. Mean FA, ADC, and longitudinal and transverse diffusivities were calculated within each ROI. Concordance correlations were derived by comparing ROI DTI values among each of the 5 magnets. RESULTS: Mean concordance for FA was 0.96; for both longitudinal and transverse diffusivities, it was 0.93; and for ADC, it was 0.88. Mean scan-rescan concordance was 0.96-0.97 for all DTI measures. Concordance correlations within platforms were, in general, better than those between platforms for all DTI measures (mean concordance of 0.96). CONCLUSIONS: We found that a 3T magnet and high-angular-resolution pulse sequence yielded comparable DTI measurements across different MR imaging magnets and platforms. Our results indicate that FA is the most comparable measure across magnets, followed by individual diffusivities. The comparability of DTI measures between different magnets supports the feasibility of multicentered clinical trials by using DTI as an outcome measure.

Reduced tuberculosis case notification associated with scaling up antiretroviral treatment in rural Malawi.

OBJECTIVE: To report on the trends in new and recurrent tuberculosis (TB) case notifications in a rural district of Malawi that has embarked on large-scale roll-out of antiretroviral treatment (ART). METHODS: Descriptive study analysing TB case notification and ART enrolment data between 2002 and 2009. RESULTS: There were a total of 10,070 new and 755 recurrent TB cases. ART scale-up started in 2003, and by 2007 an estimated 80% ART coverage had been achieved and was sustained thereafter. For new TB cases, an initial increase in case notifications in the first years after starting ART (2002-2005) was followed by a highly significant and sustained decline from 259 to 173 TB cases per 100,000 population (χ(2) for trend 261, P < 0.001, cumulative reduction for 2005-2009 = 33%, 95%CI 27-39). For recurrent TB, the initial increase was followed by a significant drop, from 20 to 15 cases/100,000 (χ(2) for linear trend = 8.3, P = 0.004, constituting a 25% (95%CI 9-49) cumulative reduction between 2006 and 2009. From 2005 to 2009, ART averted an estimated 1164 (95%CI 847-1480) new TB cases and 78 (95%CI 23-151) recurrent TB cases. CONCLUSIONS: High ART implementation coverage is associated with a very significant declining trend in new and recurrent TB case notifications at population level.

Course of poly(4-aminodiphenylamine)/Ag nanocomposite formation through UV-vis spectroscopy.

Kinetics of chemical oxidative polymerization of 4-aminodiphenylamine (4ADPA) was followed in aqueous 1 M p-toluene sulfonic acid (p-TSA) using silver nitrate (AgNO3) as an oxidant by UV-vis spectroscopy. The medium was found to be clear and homogeneous during the course of polymerization. The absorbances corresponding to the intermediate and the polymer were followed for different concentrations of 4ADPA and AgNO3 and at different reaction time. The appearance of a band around 450 nm during the initial stages of polymerization corresponds to the plasmon resonance formed by the reduction of Ag+ ions. Rate of poly(4-aminodiphenylamine)/Ag nanocomposite (RP4ADPA/AgNC) was determined for various reaction conditions. R(P4ADP/AgNC) showed second order power dependence on 4ADPA and first order dependence on AgNO3. The observed order dependences of 4ADPA and AgNO3 on the formation of P4ADPA/AgNC were used to deduce a rate equation for the reaction. Rate constant for the reaction was determined through different approaches. The good agreement between the rate constants obtained through different approaches justifies the selection of rate equation.

Antiretroviral therapy for HIV prevention: many concerns and challenges, but are there ways forward in sub-Saharan Africa?

Scientists from the WHO have presented a theoretical mathematical model of the potential impact of universal voluntary HIV testing and counselling followed by immediate antiretroviral therapy (ART). The results of the model suggests that, in a generalised epidemic as severe as that in sub-Saharan Africa (SSA), HIV incidence may be reduced by 95% in 10 years and that this approach may be cost effective in the medium term. This offers a 'ray of hope' to those who have thus far only dreamed of curbing the HIV/AIDS epidemic in SSA, as until now the glaring truth has been pessimistic. When it comes to ART, approximately 7 of 10 people who clinically need ART still do not receive it. From an epidemic point of view, for every person placed on ART an estimated four to six others acquire HIV. The likelihood of achieving the targets of the Millennium Development Goals for 2015 and universal ART access by 2010 are thus extremely low. A new window of opportunity may have now opened, but there are many unanswered feasibility and acceptability issues. In this paper, we highlight four key operational challenges linked to acceptability and feasibility and discuss possible ways forward to address them.

Task shifting in HIV/AIDS: opportunities, challenges and proposed actions for sub-Saharan Africa.

Sub-Saharan Africa is facing a crisis in human health resources due to a critical shortage of health workers. The shortage is compounded by a high burden of infectious diseases; emigration of trained professionals; difficult working conditions and low motivation. In particular, the burden of HIV/AIDS has led to the concept of task shifting being increasingly promoted as a way of rapidly expanding human resource capacity. This refers to the delegation of medical and health service responsibilities from higher to lower cadres of health staff, in some cases non-professionals. This paper, drawing on Médecins Sans Frontières' experience of scaling-up antiretroviral treatment in three sub-Saharan African countries (Malawi, South Africa and Lesotho) and supplemented by a review of the literature, highlights the main opportunities and challenges posed by task shifting and proposes specific actions to tackle the challenges. The opportunities include: increasing access to life-saving treatment; improving the workforce skills mix and health-system efficiency; enhancing the role of the community; cost advantages and reducing attrition and international 'brain drain'. The challenges include: maintaining quality and safety; addressing professional and institutional resistance; sustaining motivation and performance and preventing deaths of health workers from HIV/AIDS. Task shifting should not undermine the primary objective of improving patient benefits and public health outcomes.

Out-of-pocket costs of AIDS care in China: are free antiretroviral drugs enough?

Financial access to HIV care and treatment can be difficult for many people in China, where the government provides free antiretroviral drugs but does not cover the cost of other medically necessary components, such as lab tests and drugs for opportunistic infections. This article estimates out-of-pocket costs for treatment and care that a person living with HIV/AIDS in China might face over the course of one year. Data comes from two treatment projects run by Médecins Sans Frontières in Nanning, Guangxi Province and Xiangfan, Hubei Province. Based on the national treatment guidelines, we estimated costs for seven different patient profiles ranging from WHO Clinical Stages I through IV. We found that patients face significant financial barriers to even qualify for the free ARV program. For those who do, HIV care and treatment can be a catastrophic health expenditure, with cumulative patient contributions ranging from approximately US$200-3939/year in Nanning and US$13-1179/year in Xiangfan, depending on the patient's clinical stage of HIV infection. In Nanning, these expenses translate as up to 340% of an urban resident's annual income or 1200% for rural residents; in Xiangfan, expenses rise to 116% of annual income for city dwellers and 295% in rural areas. While providing ARV drugs free of charge is an important step, the costs of other components of care constitute important financial barriers that may exclude patients from accessing appropriate care. Such barriers can also lead to undesirable outcomes in the future, such as impoverishment of AIDS-affected households, higher ARV drug-resistance rates and greater need for complex, expensive second-line antiretroviral drugs.

Reduced meiotic recombination on the XY bivalent is correlated with an increased incidence of sex chromosome aneuploidy in men with non-obstructive azoospermia.

Both aberrant meiotic recombination and an increased frequency of sperm aneuploidy have been observed in infertile men. However, this association has not been demonstrated within individual men. The purpose of this study was to determine the association between the frequency of recombination observed in pachytene spermatocytes and the frequency of aneuploidy in sperm from the same infertile men. Testicular tissue from seven men with non-obstructive azoospermia (NOA) and six men undergoing vasectomy reversal (controls) underwent meiotic analysis. Recombination sites were recorded for individual chromosomes. Testicular and ejaculated sperm from NOA patients and controls, respectively, were tested for aneuploidy frequencies for chromosomes 9, 21, X and Y. There was a significant increase in the frequency of pachytene cells with at least one achiasmate bivalent in infertile men (12.4%) compared with controls (4.2%, P = 0.02). Infertile men also had a significantly higher frequency of sperm disomy than controls for chromosomes 21 (1.0% versus 0.24%, P = 0.001), XX (0.16% versus 0.03%, P = 0.004) and YY (0.12% versus 0.03%, P = 0.04). There was a significant correlation between meiotic cells with zero MLH1 foci in the sex body and total sex chromosome disomy (XX + YY + XY) in sperm from men with NOA (r = 0.79, P = 0.036).

The relationship between meiotic recombination in human spermatocytes and aneuploidy in sperm.

BACKGROUND: We have previously demonstrated that a decreased recombination frequency between human X and Y chromosomes is associated with the production of aneuploid 24,XY sperm. This study's aim was to determine the relationship between recombination frequency in human pachytene spermatocytes and aneuploidy frequencies in individual chromosomes in sperm from the same men. METHODS: Six previously fertile vasectomy reversal patients donated testicular tissue for meiotic analysis of pachytene spermatocytes using immunocytogenetic techniques for visualization of the synaptonemal complex and recombination sites (MLH1). Individual meiotic chromosomes were identified with centromere-specific multicolor fluorescence in situ hybridization (FISH), and the number of MLH1 signals was recorded for individual chromosomes. An ejaculated sperm sample was obtained from each patient 2-26 months post-reversal for FISH analysis of sperm aneuploidy frequencies of chromosomes 1, 9, 13, 21, X and Y. RESULTS: There was no significant correlation between meiotic recombination frequency and sperm aneuploidy for any individual chromosome. Similarly, there was no correlation between aneuploid sperm and bivalents with no recombination. CONCLUSIONS: The study provides unique data on intra-individual human recombination and aneuploidy events. It also demonstrated for the first time that men do not have an increased frequency of sperm aneuploidy 5-9 years post-vasectomy.

Real-time RT-PCR detection of disseminated tumour cells in bone marrow has superior prognostic significance in comparison with circulating tumour cells in patients with breast cancer.

This study assessed the ability of real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis to detect disseminated epithelial cells (DEC) in peripheral blood (PB) and bone marrow (BM) of patients with breast cancer (BC). Detection of DEC in BM is an obvious choice in BC, but blood sampling is more convenient. The aim of this study was to evaluate whether the detection of DEC in either PB or BM predicts overall survival (OS). Peripheral blood and BM samples were collected from 148 patients with primary (stage M0, n=116/78%) and metastatic (stage M+, n=32/21%) BC before the initiation of any local or systemic treatment. Peripheral blood of healthy volunteers and BM of patients with a nonmalignant breast lesion or a haematological malignancy served as the control group. Disseminated epithelial cells was detected by measuring relative gene expression (RGE) for cytokeratin-19 (CK-19) and mammaglobin (MAM), using a quantitative RT-PCR detection method. The mean follow-up time was 786 days (+/- 487). Kaplan-Meier analysis was used for predicting OS. By taking the 95 percentile of the RGE of CK-19 (BM: 26.3 and PB: 58.7) of the control group as cutoff, elevated CK-19 expression was detected in 42 (28%) BM samples and in 22 (15%) PB samples. Mammaglobin expression was elevated in 20% (both PB and BM) of the patients with BC. There was a 68% (CK-19) and 75% (MAM) concordance between PB and BM samples when classifying the results as either positive or negative. Patients with an elevated CK-19 or MAM expression in the BM had a worse prognosis than patients without elevated expression levels (OS: log-rank test, P=0.0045 (CK-19) and P=0.025 (MAM)). For PB survival analysis, no statistical significant difference was observed between patients with or without elevated CK-19 or MAM expression (OS: log-rank test, P=0.551 (CK-19) and P=0.329 (MAM)). Separate analyses of the M0 and M+ patients revealed a marked difference in OS according to the BM CK-19 or MAM status in the M+ patient group, but in the M0 group, only MAM expression was a prognostic marker for OS. Disseminated epithelial cells, measured as elevated CK-19 or MAM mRNA expression, could be detected in both PB and BM of patients with BC. Only the presence of DEC in BM was highly predictive for OS. The occurrence of DEC in the BM is probably less time-dependent and may act as a filter for circulating BC cells. The use of either larger volumes of PB or performing an enrichment step for circulating tumour in blood cells might improve these results.

Compartmentalized signalling of Ras.

Ras proteins associate with cellular membranes by virtue of a series of post-translational modifications of their C-terminal CAAX sequences. The discovery that two of the three enzymes that modify CAAX proteins are restricted to the endoplasmic reticulum led to the recognition that all nascent Ras proteins transit endomembranes en route to the PM (plasma membrane) and that at steady-state N-Ras and H-Ras are highly expressed on the Golgi apparatus. To test the hypothesis that Ras proteins on internal membranes can signal, we developed a fluorescent probe that reports when and where in living cells Ras becomes active. We found that growth factors stimulated rapid and transient activation of Ras on the PM followed by delayed and sustained activation on the Golgi. We mapped one pathway responsible for this activity as involving PLCgamma (phospholipase Cgamma)/DAG (diacylglycerol)+Ca2+/RasGRP1. Using mammalian cells and fission yeast, we have shown that differential localization of activated Ras preferentially activates distinct signalling pathways. In very recent work, we have found that (i) the subcellular localization of K-Ras can be acutely modulated by phosphorylation of its C-terminal hypervariable region by PKC, (ii) among the membranes upon which phosphorylated K-Ras accumulates is the outer mitochondrial membrane and (iii) phosphorylated, internalized K-Ras promotes apoptosis. Thus the signalling output of Ras depends on its subcellular localization.

The effect of cold storage on recombination frequencies in human male testicular cells.

Meiotic recombination is essential for the segregation of homologous chromosomes and formation of normal haploid gametes. Decreased recombination is associated with the production of aneuploid sperm in humans. MLH1, a DNA mismatch repair protein, was recently found to mark the sites of recombination in humans. Newly developed immunofluorescence techniques to identify MLH1 foci on synaptonemal complexes (SCs) in pachytene cells from testicular tissue have opened up a new avenue of research on meiotic recombination. Future studies on normal and abnormal recombination in early meiosis will further research in human reproduction and genetics. However, the availability of testicular material will always be a major limiting factor in this kind of study. In order to obtain an adequate number of samples and samples of particular research interest, it is often of benefit to obtain samples from distant regions. Therefore, it is necessary to determine whether the quality of samples and accuracy of MLH1 frequencies change after transporting testicular samples from a distance. In the present study, we examined the recombination frequencies (numbers of MLH1 foci using immunofluorescence techniques) in 6 normal testicular samples. Each sample was split and analyzed in the fresh state and after storage on ice for two days, mimicking overnight courier air transport. The results showed no significant difference in the quality of the SC preparations or in the number of MLH1 foci between these two groups. These results demonstrate that testicular specimens may be shipped on ice without compromising data on chromosome pairing and recombination in early meiosis.

Meiotic defects in a man with non-obstructive azoospermia: case report.

Infertile men have an increased frequency of aneuploid sperm. We have determined that decreased recombination is associated with the production of aneuploid sperm in humans. The aim of this study was to determine whether some cases of infertility are associated with decreased meiotic recombination. Analysis of the early stages of meiosis was performed in a 33-year-old man with non-obstructive azoospermia. Newly developed immunocytogenetic techniques were used to identify the synaptonemal complex (SC) in various stages of prophase. Antibodies to meiotic proteins identified the SC (SYN1/SCP3), the centromere (CREST) and recombination sites (MLH1). Only 36 meiotic spreads were recovered from the infertile man, compared with hundreds available from controls. One-third of the cells were in zygotene compared with 4% in controls, demonstrating an inability of bivalents to synapse and progress to pachytene. The infertile man had a greatly reduced frequency of recombination, with a mean of only 32.7 MLH1 foci/cell (range 1-60) compared with 46.0 (range 21-62) in control donors. A high proportion of cells (73%) contained at least one autosomal bivalent with zero MLH1 foci, compared with only 4.5% in control donors. Discontinuities in the SC were also more prevalent (68% of cells versus 26% in controls). This is the first demonstration of dramatic pachytene-stage abnormalities in an infertile man using these powerful new immunocytogenetic techniques.

The sequence and gene characterization of a 400-kb candidate region for IDDM4 on chromosome 11q13.

Type 1 diabetes is a complex disorder with interaction of both genetic and environmental factors. One of the loci, IDDM4, has been mapped to chromosome 11q13, with evidence of association to two markers, D11S1917 and H0570polyA. To identify putative candidate genes for IDDM4, we have constructed a 400-kb clone contig in this region and sequenced the clones. We have also sequenced the orthologous DNA from mouse. Previously, we identified a cDNA for the low-density lipoprotein receptor-related protein 5 gene (LRP5) 3 kb distal to H0570polyA. We have now determined the exon-intron structure of this gene. Detailed sequence analysis has identified a further three genes in this region: the CGI-85 gene (previously identified by W.-C. Lin) and two novel genes, C11orf24 and C11orf23. The C11orf24 gene has no known similarity to other genes, and its function is unknown. C11orf23 has similarity to the SIT4 (sporulation-induced transcript 4)-associated protein (SAP) family of yeast proteins, which are involved in regulation of the cell cycle. The full-length C11orf23 cDNA is the first mammalian orthologue of the yeast SAP family to be identified. Identification of these four genes in a 400-kb region of the IDDM4 region underpins our strategy to identify the IDDM4 locus.

Neuroprotective and behavioral efficacy of nerve growth factor-transfected hippocampal progenitor cell transplants after experimental traumatic brain injury.

OBJECT: Immortalized neural progenitor cells derived from embryonic rat hippocampus (HiB5), were transduced ex vivo with the gene for mouse nerve growth factor (NGF) to secrete NGF (NGF-HiB5) at 2 ng/hr/10(5) cells in culture. METHODS: Fifty-nine male Wistar rats weighing 300 to 370 g each were anesthetized with 60 mg/kg sodium pentobarbital and subjected to lateral fluid-percussion brain injury of moderate severity (2.3-2.4 atm, 34 rats) or sham injury (25 rats). At 24 hours postinjury, 2 microl (150,000 cells/microl) of [3H]thymidine-labeled NGF-HiB5 cells were transplanted stereotactically into three individual sites in the cerebral cortex adjacent to the injury site (14 rats). Separate groups of brain-injured rats received nontransfected (naive [n])-HiB5 cells (12 animals) or cell suspension vehicle (eight animals). One week postinjury, animals underwent neurological evaluation for motor function and cognition (Morris water maze) and were killed for histological, autoradiographic, and immunocytochemical analysis. Viable HiB5 cell grafts were identified in all animals, together with reactive microglia and macrophages located throughout the periinjured parenchyma and grafts (OX-42 immunohistochemistry). Brain-injured animals transplanted with either NGF-HiB5 or n-HiB5 cells displayed significantly improved neuromotor function (p < 0.05) and spatial learning behavior (p < 0.005) compared with brain-injured animals receiving microinjections of vehicle alone. A significant reduction in hippocampal CA3 cell death was observed in brain-injured animals receiving transplants of NGF-HiB5 cells compared with those receiving n-HiB5 cells or vehicle (p < 0.025). CONCLUSIONS: This study demonstrates that immortalized neural stem cells that have been retrovirally transduced to produce NGF can markedly improve cognitive and neuromotor function and rescue hippocampal CA3 neurons when transplanted into the injured brain during the acute posttraumatic period.