[Bioinformatics-based analysis of the effect of general Transcription Factor IIH on prognosis of Prostate cancer].

Objective: To investigate the genetic and expression characteristics of transcription factor IIH (TFIIH) in pre-initiationcomplex in prostate cancer (PCa) and its relationship with prostate cancer progression. Methods: Analyzing the expression characteristics and clinical signification of TFIIH subunits about 495 cases of PCa and 52 cases of adjacent cancer in The Cancer Genome Atlas-Prostate adenocarcinoma (TCGA-PRAD) database. PCa microarray chip was used to verify the correlation between the key factor General Transcription Factor IIH Subunit 4 (GTF2H4) in TFIIH and clinical features. Results: The 495 patients with PCa were (61.01±6.82) years old.The mRNA expression of ERCC3、GTF2H4 and MNAT1 were high in PCa tissues with GS≥8(P<0.05). The expression of GTF2H4 and MNAT1 were relevant to the pathological stages(P<0.05). High expression of GTF2H4 has higher biochemical recurrence (BCR) rate in PCa patients(HR=2.47, 95%CI:1.62-3.77, P<0.001), which has better predictive effect of BCR in PCa patients(The 3rd, 5th, and 7th year AUC all>0.7) than other subunits, and it has been verified in four additional databases. Single-factor Cox regression analysis showed that GTF2H4 were risk factors for BCR (HR=2.470, 95%CI:1.620-3.767, P<0.001) and GTF2H5 were protective factors(HR=0.506,95%CI: 0.336-0.762, P=0.001). The results of immunohistochemical staining showed that the protein expression of GTF2H4 was correlated with the clinical features of PCa patients.The differences of the above results were statistically significant. Conclusion: GTF2H4, the key factor of TFIIH, is highly expressed in PCa and indicates a poor prognosis.

[Activation of GPER inhibts proliferation and autophagy in prostatic epithelial cells].

Objective: To investigate the effect of G protein-coupled estrogen receptor (GPER) on proliferation and autophagy in prostatic epithelial cells. Methods: Cell Counting Kit-8 (CCK8) assay was used to observe the growth of BPH-1 and RWPE-1 cells after treating with or not with estradiol or GPER selective agonist G1. Autophagy was quantified with Western blot and Cyto-ID autophagy detection kit after treating with estradiol, G1 or both G1 and G15 in the same cells. Results: The OD value in estrogen group and G1 group was significantly lower than those in control group (P<0.01). Compared with control group, Western blot and Cyto-ID green reagent staining revealed that the ratio of LC3Ⅱ/LC3Ⅰ and the relative fluorescence intensity of BPH-1 and RWPE-1 cells were decreased in G1 group and estradiol group (P<0.01). Pretreatment with G15 reversed the effect of G1 (P<0.05). Conclusion: The activation of GPER leads to the inhibition of autophagy and cell proliferation.

[Effect of interleukin-6 promoter DNA methylation on the pathogenesis of systemic lupus erythematosus].

Objective: To analyze peripheral blood interleukin-6 (IL-6) promoter DNA methylation status and its clinical significance in patients with systemic lupus erythematosus (SLE). Methods: Blood samples of 41 adult patients with SLE and 20 healthy controls were collected.The methylation status of IL-6 promoter was determined by methylation specific polymerase chain reaction (MSP). The IL-6 expression was detected by real-time PCR.Correlations between IL-6 promoter methylation status and clinical features or laboratory findings in patients with SLE were analyzed. Results: The levels of IL-6 mRNA were significantly higher in peripheral blood of SLE.DNA methylation levels of IL-6 promoter were reduced in SLE patients as compared with healthy controls.The methylation status and expression of IL-6 in peripheral blood reflected the levels in peripheral blood mononuclear cells (PBMCs). Significantly positive correlation was found between IL-6 hypomethylation and renal disorder, as well as hypocomplementemia in patients with SLE. Conclusion: Hypomethylation of interleukin-6 promoter in peripheral blood might be involved in the etiology of SLE.

[The impact of weight management and related diuretic medication intervention based on body weight changes on cardiac function and re-hospitalization rate in patients with chronic congestive heart failure].

Objective: To explore the impact of weight management and related medication intervention based on body weight changes on cardiac function among patients with chronic congestive heart failure (CHF). Methods: Using prospective, randomized, controlled study methods, consecutive CHF patients, who hospitalized in our department from June 2014 to June 2016 (n=350), were randomly divided into intervention group (n=175) and control group (n=175). Patients in the intervention group received weight management guidance and the post discharge diuretic drugs regimen was adjusted based on body weight changes. The control group received routine medical care post discharge. Left ventricular ejection fraction (LVEF), B type natriuretic peptide precursor (NT-proBNP), 6 minutes walk distance and NYHA classification at one day before discharge and after 6 months were compared between the two groups respectively. Results: Follow-up visit data were not available from 6 patients in the control and intervention group respectively. NYHA classification, LVEF, NT-proBNP and 6 minutes walk distance were similar between the two groups at one day before discharge (all P>0.05). After 6 months, the LVEF and 6 minutes walk distance were significantly higher while NT-proBNP level was significantly lower in the intervention group compared to the control group (all P<0.01). Meanwhile, the LVEF and 6 minutes walk distance were significantly increased, while NT-proBNP was significantly reduced at 6 months post discharge compared to one day before discharge in the intervention group (all P<0.01). The LVEF was also significantly improved (P=0.035), but the NT-proBNP and 6 minutes walk distance were similar (P were 0.328 and 0.807 respectively) at 6 months after discharge compared to one day before discharge in the control group. The NYHA classification was significantly lower in intervention group and in control group at 6 months after discharge compared to one day before discharge (Z=5.154, P<0.01 and Z=10.497, P<0.01), and the NYHA classification improved more in the intervention group than in control group at 6 months after discharge (Z=9.235, P<0.01). The re-hospitalization rate of CHF patients in intervention group was 11.83% (20/169), which was significantly lower than the control group (33.14% (56/169), χ(2)=21.99, P<0.01). At 6 months follow up, body weight remained unchanged in the intervention group, while body weight tended to be higher in the control group compared to one day before discharge. Conclusion: The weight management and diuretic drug regimen adjudgment intervention based on body weight changes can improve cardiac function and reduced re-hospitalization rate in CHF patients.

Transcription factor and bone marrow stromal cells in osseointegration of dental implants.

Titanium implants are widely used in dental clinics and orthopaedic surgery. However, bone formation surrounding the implant is relatively slow after inserting the implant. The current study assessed the effects of bone marrow stromal cells (BMSCs) with forced expression of special AT-rich sequence-binding protein 2 (SATB2) on the osseointegration of titanium implants. To determine whether SATB2 overexpression in BMSCs can enhance the osseointegration of implants, BMSCs were infected with the retrovirus encoding Satb2 (pBABE-Satb2) and were locally applied to bone defects before implanting the titanium implants in the mouse femur. Seven and twenty-one days after implantation, the femora were isolated for immunohistochemical (IHC) staining, haematoxylin eosin (H&E) staining, real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), and micro-computed tomography (µCT) analysis. IHC staining analysis revealed that SATB2-overexpressing BMSCs were intensely distributed in the bone tissue surrounding the implant. Histological analysis showed that SATB2-overexpressing BMSCs significantly enhanced new bone formation and bone-to-implant contact 3 weeks after implantation. Real-time qRT-PCR results showed that the local delivery of SATB2-overexpressing BMSCs enhanced expression levels of potent osteogenic transcription factors and bone matrix proteins in the implantation sites. µCT analysis demonstrated that SATB2-overexpressing BMSCs significantly increased the density of the newly formed bone surrounding the implant 3 weeks post-operatively. These results conclude that local delivery of SATB2-overexpressing BMSCs significantly accelerates osseointegration of titanium implants. These results provide support for future pharmacological and clinical applications of SATB2, which accelerates bone regeneration around titanium implants.

Single sevoflurane exposure decreases neuronal nitric oxide synthase levels in the hippocampus of developing rats.

BACKGROUND: The use of general anaesthetics in young children and infants has raised concerns regarding the adverse effects of these drugs on brain development. Sevoflurane might have harmful effects on the developing brain; however, these effects have not been well investigated. METHODS: Postnatal day 7 (P7) Sprague-Dawley rats were continuously exposed to 2.3% sevoflurane for 6 h. We used the Fox battery test and Morris water maze (MWM) to examine subsequent neurobehavioural performance. Cleaved caspase-3 and neuronal nitric oxide synthase (nNOS) were quantified by immunoblotting, and the Nissl staining was used to observe the histopathological changes in the hippocampus. RESULTS: A single 6 h sevoflurane exposure at P7 rats resulted in increased cleaved caspase-3 expression and decreased nNOS levels in the hippocampus, and induced the loss of pyramidal neurones in the CA1 and CA3 subfields of the hippocampus at P7-8. These changes were accompanied by temporal retardation of sensorimotor reflexes. However, neither the Fox battery test at P1-21 nor the MWM test at P28-32 showed differences between the air- and sevoflurane-treated groups. CONCLUSIONS: Although early exposure to sevoflurane increases activated caspase-3 expression and neuronal loss and decreases nNOS in the neonatal hippocampus, it does not affect subsequent neurobehavioural performances in juvenile rats.

The impact of local colleges' interference in middle school students' family psychological intervention on the psychological health status of students learning at home - a case study of northern Guangdong.

OBJECTIVE: Using college psychological resources, this paper attempts to intervene in the family psychology of middle school students learning at home during the epidemic in northern Guangdong. Focusing on the impact of family system on the psychological health status of middle school students learning at home, it provides reference for targeted family psychological intervention and treatment of students. SUBJECTS AND METHODS: The "Psychological Health Survey Questions for Middle School Students Learning at Home during the Epidemic" was compiled to conduct a class-based random sampling survey of primary and secondary schools in northern Guangdong. Family psychological intervention is provided for key groups. RESULTS: (1) The middle school students' psychological health level was above average on the whole, but with great individual differences. (2) Families have a significant impact on students' psychological health, among which parents' occupation, family integrity, family economy, family atmosphere, and the number of children in the family all exert a significant impact on middle school students' psychological health. (3) Stepwise regression analysis reveals that the six factors of gender, grade, ethnicity and place of residence, family economy and atmosphere in the family environment system are included in the regression equation, explaining 11.6% of middle school students' psychological health. (4) Family psychological intervention significantly improves middle school students' psychological health. CONCLUSIONS: Local colleges' interference in middle school students' family psychological intervention can effectively improve psychological health of middle school students learning at home. Society, families and schools should value family psychological construction, and effectively unite social forces to jointly promote students' psychological health.

[Application and research progress of digital virtual simulated design in dental esthetic rehabilitation].

In dental esthetic rehabilitation, patients pay great attention to the rehabilitative esthetic effect before teeth preparation, and this is also an important content of doctor-patient communication. Along with the development and combined application of intraoral scan, three-dimensional (3D) face scan, digital design, numerical control machining and 3D printing technology, digital technology is gradually applied to the virtual simulated design before irreversible operation in dental esthetic rehabilitation. Digital technology can be used in dentistry to simulate the esthetic outcome in advance, to assist communication among the dentists, patients and dental technicians, and to realize satisfactory outcome in the final restorations precisely, which, as a result, increases the clinical satisfaction. This review focuses on the application of digital virtual simulated design technology in dental esthetic rehabilitation, analyzes the current research development, deficiency and future prospects, so as to provide guidance for clinical diagnosis and treatment.

[Anatomical characteristics of profunda artery perforator flap in the posteromedial femoral region and its application in the reconstruction of oral and maxillofacial defects].

Objective: To investigate the anatomical basis for the preparation of the profunda artery perforator flap (PAPF) in the posteromedial femoral region and its application in the reconstruction of oral and maxillofacial defects. Methods: Six lower limbs of Chinese adult cadavers were micro-surgically dissected. CT angiography (CTA) data of bilateral lower limbs of 6 patients was also collected retrospectively. The number, external diameter, pedicle length, and distribution of perforators in the posteromedial femoral region were recorded from the specimens and CTA data. Meanwhile, 10 patients with oral squamous cell carcinoma in the Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University from August 2018 to June 2021 were treated with the PAPF. At each follow-up, contour and function of recipient and donor site, as well as swallowing and speech function were evaluated. Results: A total of 19 profunda artery perforator were identified in 6 lower limb specimens. The outer diameter at the beginning of the source artery was (2.34±0.25) mm and the total length of the pedicle was (11.12±1.06) cm. CTA data analysis of 12 legs identified 15 perforators of profunda artery in the posteromedial region. Eleven perforators were septocutaneous, including 2 perforators with a common trunk, while the remaining 4 perforators were musculocutaneous. As for different patterns of perforators (septocutaneous perforators, musculocutaneous perforators and perforators with a common trunk), the longitudinal distance to the pubic tubercle was (19.95±2.43), (21.84±2.54) and (19.48±0.55) cm respectively. The horizontal distance to the posterior edge of gracilis was (3.54±1.10), (3.72±0.30) and (3.85±1.48) cm, respectively. The initial diameters of perforators was (2.4±0.4), (2.6±0.6) and 1.9 mm respectively. Ten cases of the profunda artery perforator flaps survived successfully after operation. The flap sizes ranged from 8 cm×6 cm to 12 cm×7 cm. The patients were evaluated at 1, 3 and 6 months, and with 6 months interval ever since. During the follow-up, the shape of the recipient site was ideal, and the swallowing and language functions were not significantly affected. There was only linear scar in the donor area, and the function of the thigh was basically normal. Conclusions: PAPF possessed a good anatomic stability, suitable vascular pedicle length and diameter, minor influence to the donor area, sufficient amount tissue with good quality. It is an ideal choice for head and neck reconstruction.

Ethanol dually modulates GABAergic synaptic transmission onto dopaminergic neurons in ventral tegmental area: role of mu-opioid receptors.

The mesolimbic dopaminergic system, originating from the ventral tegmental area (VTA) is implicated in the rewarding properties of ethanol. VTA dopaminergic neurons are under the tonic control of GABAergic innervations. Application of GABAergic agents changes ethanol consumption. However, it is unclear how acute ethanol modulates GABAergic inputs to dopaminergic neurons in the VTA. This report describes ethanol at clinically relevant concentrations (10-40 mM) dually modulates inhibitory postsynaptic currents (IPSCs). IPSCs were mediated by GABA(A) receptors and were recorded from VTA dopaminergic neurons in acute midbrain slices of rats. Acute application of ethanol reduced the amplitude and increased the paired pulse ratio of evoked IPSCs. Ethanol lowered the frequency but not the amplitude of spontaneous IPSCs. Nevertheless, ethanol had no effect on miniature IPSCs recorded in the presence of tetrodotoxin. These data indicate that ethanol inhibits GABAergic synaptic transmission to dopaminergic neurons by presynaptic mechanisms, and that ethanol inhibition depends on the firing of GABAergic neurons. Application of CGP 52432, a GABA(B) receptor antagonist, did not change ethanol inhibition of IPSCs. Tyr-d-Ala-Gly-N-Me-Phe-Gly-ol enkephalin (DAMGO), a mu-opioid receptor agonist, conversely, silenced VTA GABAergic neurons and inhibited IPSCs. Of note, in the presence of a saturating concentration of DAMGO (3 microM), ethanol potentiated the remaining IPSCs. Thus, ethanol dually modulates GABAergic transmission to dopaminergic neurons in the VTA. Ethanol modulation depends on the activity of VTA GABAergic neurons, which were inhibited by the activation of mu-opioid receptors. This dual modulation of GABAergic transmission by ethanol may be an important mechanism underlying alcohol addiction.

[Associations of obesity and physical activity with cognition in people aged 50 and above in Shanghai].

Objective: To investigate the associations of obesity and physical activity with cognition in the elderly. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. The subjects' body weight, body height, waist circumference and hip circumference were measured to calculate body mass index (BMI) and waist-hip ratio (WHR), and the data on self-reported physical activity level were collected through questionnaire survey. A comprehensive battery of cognitive tests was conducted to assess subjects' cognitive functions, including verbal recall, forward digit span (FDS), backward digit span (BDS), and verbal fluency (VF). General linear model was used to examine the associations of BMI, WHR and physical activity with cognition. Results: A total of 7 913 participants were included, with a median age of 60 years. Age, sex, education level, income level, BMI, WHR and physical activity level were significantly associated with cognitive scores in univariate analysis. After adjusted for age, sex, education level and income level, BMI was no longer significantly associated with cognitive scores in all cognitive functions (all P>0.01). WHR was significantly associated with VF score (P<0.01). Abdominally obese participants had lower VF score than non-abdominally obese participants (P<0.01). Physical activity level was significantly associated with all cognitive functions (P<0.01). Compared with participants with moderate physical activity level, participants with low physical activity level had lower scores in all cognitive functions (P<0.01). Conclusion: Abdominal obesity and low physical activity level were negatively associated with cognition level in the elderly, suggesting that waist circumference control and physical activity might help maintain cognition in the elderly.

The slow wave component of retinal activity in rd/rd mice recorded with a multi-electrode array.

We investigated the differences in the retinal activity between normal and degenerate retina. Multi-electrode recordings were performed in in vitro mice retinas. Only short duration (<2 ms) retinal spikes were recorded in normal mice by postnatal day 28. However, in rd/rd mice, a slow wave component with approximately 100 ms duration was also recorded along with the spikes. We attempted to understand the mechanism of this slow wave component in degenerate retina by applying various synaptic blockers. With CNQX/AP-7, the glutamate antagonist (n = 7), the slow wave component disappeared while the normally less-dominant retinal spikes became more apparent. With strychnine, the glycine antagonist (n = 3) or picrotoxin, GABA antagonist (n = 3), the amplitude of the slow wave component increased. These suggest that a stronger excitatory glutamate input from bipolar cells to ganglion cells is the main contributor to this slow wave component in rd/rd mice.

Glycine blocks long-term potentiation of GABAergic synapses in the ventral tegmental area.

The mesocorticolimbic dopamine system, originating in the ventral tegmental area (VTA) is normally constrained by GABA-mediated synaptic inhibition. Accumulating evidence indicates that long-term potentiation of GABAergic synapses (LTPGABA) in VTA dopamine neurons plays an important role in the actions of drugs of abuse, including ethanol. We previously showed that a single infusion of glycine into the VTA of rats strongly reduces ethanol intake for 24h. In the current study, we examined the effect of glycine on the electrophysiological activities of putative dopamine VTA neurons in midbrain slices from ethanol-naïve rats. We report here that a 15-min exposure to 10 µM glycine prevented trains of high-frequency stimulation (HFS) from producing LTPGABA, which was rescued by the glycine receptor (GlyR) antagonist strychnine. Glycine also concentration-dependently decreased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs). By contrast, glycine pretreatment did not prevent potentiation of inhibitory postsynaptic currents (IPSCs) during a continuous exposure to the nitric oxide (NO) donor, SNAP (S-nitroso-N-acetylpenicillamine), or a brief exposure to 10 µM glycine and 10 µM NMDA (N-methyl-D-aspartate), an agonist of NMDA-type glutamate receptors. Thus, the blockade of LTPGABA by glycine is probably resulted from suppressing glutamate release by activating the GlyRs on the glutamatergic terminals. This effect of glycine may contribute to the reduction in ethanol intake induced by intra-VTA glycine observed in vivo.

Protein kinase C epsilon is involved in ethanol potentiation of glycine-gated Cl(-) current in rat neurons of ventral tegmental area.

Previously, we demonstrated that ethanol potentiates glycine current (I(Gly)) in 35% of neurons freshly isolated from the ventral tegmental area (VTA) of rats (J. Pharmacol. Exp. Ther. 296 (2001) 77). In the present study, we examined the role of protein kinase C (PKC) in this action of ethanol on VTA neurons from young rats. Extracellular ethanol and intracellular ATP-gamma-S when applied separately potentiated I(Gly). However, ethanol potentiation of I(Gly) was significantly reduced in neurons dialyzed with 2 mM ATP-gamma-S. Phorbol-12-myristate-13-acetate (PMA, 10 nM), a PKC activator also increased I(Gly) and reduced ethanol potentiation of I(Gly). In addition, GF109203X (0.2 microM), a PKC inhibitor antagonized the potentiation effects produced either by PMA or by ethanol. Thus, ethanol potentiation of I(Gly) may be associated with PKC activation. While intracellular application of 1,2-bis(aminophenoxy)-ethane-N,N,N,N'-tetraacetic acid, a Ca(2+) chelator or Gö6976, an inhibitor of Ca(2+)-dependent PKC had no appreciable effect on ethanol potentiation of I(Gly), translocation inhibitor peptide (PKC(epsilon)-TIP) (500 nM) significantly reduced ethanol potentiation, an action the translocation inhibitor peptide negative control (PKC(epsilon)-TIP-NC) (500 nM) did not have. These results suggest that the activation of PKC(epsilon) isoenzyme contributes to ethanol-induced potentiation of GlyR function.

Excitatory amino acid induced currents of isolated murine hypothalamic neurons and their suppression by 2,3-butanedione monoxime.

Ionic currents induced by excitatory amino acids were investigated for freshly isolated murine hypothalamic neurons with whole cell recording techniques. L-glutamate or N-methyl-D-aspartate (NMDA), in combination with glycine, resulted in a rapidly rising current which decayed in the continued presence of agonist. In contrast, kainate currents did not decay. While quisqualate-induced current maintained a steady amplitude in the continued presence of agonist, a rapid decay phase appeared at holding potentials negative to -50 mV. Co-application of 2,3-butanedione monoxime (BDM) reversibly inhibited the currents due to each agonist. Detailed study of BDM suppression of kainate-induced current revealed two components. A component with a rapid onset did not involve phosphatase action since 500 microM ATP-gamma-S or a protein kinase inhibitor (H-7, 200 microM) did not alter current suppression or recovery after BDM. Thus, the probable mechanism for this component of BDM's effect is direct block of the kainate-activated ion channel. However, preincubating neurons with 30 mM BDM reduced their subsequent response to kainate alone. This persistent effect of BDM was not seen for neurons dialyzed with a solution containing ATP-gamma-S during conventional whole cell recording. Furthermore, exposure to H-7 prevented recovery of the kainate response suppressed by preincubation in BDM. These findings suggest that BDM causes sustained suppression of the kainate response of hypothalamic neurons via a "chemical phosphatase" action.

Genistein directly blocks glycine receptors of rat neurons freshly isolated from the ventral tegmental area.

The effects of tyrosine kinase inhibitors on the glycine-induced current (I(Gly)) were studied in rat neurons freshly isolated from the ventral tegmental area (VTA). Genistein reversibly and concentration-dependently depressed I(Gly), with an IC(50) of 13 microM. Preincubation with genistein had no effect on I(Gly), indicating that genistein is effective only when glycine is bound to the receptor and channels are most likely open. Genistein depressed maximum I(Gly) without significantly changing the EC(50) for glycine. Genistein-induced inhibition of I(Gly) was sensitive to membrane voltage, being greater at positive membrane potentials. A kinetic analysis indicated that genistein lengthens the time constant of I(Gly) activation, but has no effect on deactivation or desensitization. When genistein was rapidly washed out, a transient rebound current probably reflected a faster dissociation of genistein, with respect to glycine. Results of competition experiments suggest that genistein acts on the same region of the glycine receptor as picrotoxin. Daidzein, an analog of genistein that does not act on protein kinases, also inhibited I(Gly). Co-application of lavendustin A, a specific inhibitor of tyrosine kinase, had no effect on I(Gly). Our results extend to neurons isolated from the VTA, the previous finding that genistein directly inhibits glycine receptors of hypothalamic brain slices.

Decay of ethanol-induced suppression of glycine-activated current of ventral tegmental area neurons.

We demonstrated previously that ethanol depresses glycine-induced currents in 45% of neurons freshly isolated from the ventral tegmental area (VTA) of rats (), and that protein kinase C (PKC) modulates this action of ethanol (). In the present study, we investigated the time course of this effect of ethanol on VTA neurons from young rats. For 70% of the neurons in which ethanol reduced glycine-evoked currents, this depressant effect gradually diminished during continuous superfusion with ethanol. Its action decayed faster when ethanol was applied in several brief pulses than by continuous superfusion. On the other hand, the decay was especially slower when ethanol was applied in pulses at longer intervals or by preincubation. Phorbol ester 12,13-dibutyrate (PDBu, 1 microM), an activator of PKC, also depressed glycine-induced currents. In approximately 40% (6/15) of the neurons, the effect of PDBu diminished with time and was antagonized by the specific PKC inhibitor, chelerythrine (7 microM). Chelerythrine also attenuated the ethanol-induced depression of glycine-induced currents and its time-dependent decay, thus confirming our previous evidence that PKC mediates, at least in part, the decay of the depressant effect of ethanol on glycine-induced currents of VTA neurons.

Survival of chronically-injured neurons can be prolonged by treatment with neurotrophic factors.

Axonal regeneration by chronically-injured supraspinal neurons can be enhanced by neurotrophic factor treatment at the site of injury, although the number of regenerating neurons decreases as the interval between spinal cord injury and treatment increases. This study investigated whether this decline in regenerative response could be due to continued loss of neurons during the post-injury period. Adult rats received a cervical hemisection lesion and axotomized neurons were labeled by retrograde transport of True Blue from the lesion site. Animals were killed one, four or eight weeks after injury and surviving neurons (True Blue-labeled) were counted in the red nucleus and lateral vestibular nucleus. The neuron number in the lateral vestibular nucleus was stable for eight weeks after spinal cord injury, while survival in the red nucleus decreased by 25% between four and eight weeks. To test how neurons respond to a second injury with or without trophic factor treatment, at four, eight, 14 or 22 weeks after injury the lesion cavity was enlarged by 0.5 mm in a rostral direction. Gel foam saturated with ciliary neurotrophic factor, brain-derived neurotrophic factor or basic fibroblast growth factor was placed into the cavity. Animals were killed four weeks later. Re-injury of the spinal cord caused a significant decrease in neuron survival in both the red nucleus and lateral vestibular nucleus, the effects of which were lessened by treatment with ciliary neurotrophic factor or brain-derived neurotrophic factor for the red nucleus and with ciliary neurotrophic factor for the lateral vestibular nucleus, when re-injured at four or eight weeks. Basic fibroblast growth factor did not affect neuron survival at any time post-injury. Ciliary neurotrophic factor was not effective with longer delays (14 or 22 weeks) between the initial injury and re-injury. These results indicate a delayed pattern of secondary neuronal cell loss after spinal cord injury that is exaggerated by re-injury, but which can be ameliorated by treatment with neurotrophic factors.

Axonal regeneration by chronically injured supraspinal neurons can be enhanced by exposure to insulin-like growth factor, basic fibroblast growth factor or transforming growth factor beta.

To test whether known growth factors could promote the regenerative reponse of chronically injured neurons, we exposed the injured adult rat spinal cord to insulin-like growth factor 1 (IGF-1), basic fibroblast growth factor (bFGF) or transforming growth factor beta 1 + 2 (TGFßs) 1 month after creation of a hemisection lesion. At 1 week later an autologous peripheral nerve graft was apposed to the rostral cavity wall and 1 month later Nuclear Yellow (NY) was used to retrogradely label neurons that had grown an axon into the graft. Neurons capable of axonal regeneration after a long term (5 weeks) injury were double labeled with True Blue (TB, provided at the time of hemisection lesion) and NY. Exposure to any of the three growth factors, compared to a PBS-treated control, resulted in a significant increase in the total number of regenerating supraspinal neurons, with the greatest increase after treatment with TGFßs. Treatment with TGFßs or bFGF led to a significant increase in the number of regenerating neurons in 6 out of 7 major regions (excluding the motor cortex) contributing to descending spinal pathways. Treatment with IGF-1 promoted significant regeneration only by reticular formation neurons. These results indicate that exposure to specific growth factors can enhance axonal regeneration by chronically injured neurons, thus overcoming one significant challenge to the repair of long standing structural damage to the spinal cord. © 1996 Elsevier Science Ireland Ltd. All rights reserved.