[Clinicopathologic features and prognostic analyses of locally recurrent renal cell carcinoma patients after initial surgery].

OBJECTIVE: To evaluate the clinicopathologic features and potential prognostic predictors of locally recurrent renal cell carcinoma patients after initial surgery. METHODS: Authors retrospectively analyzed data extracted from 81 patients who were treated for postoperative locally recurrence of renal cell carcinoma from January 2006 to June 2016 in the Department of Urology, Peking University First Hospital. Postoperative locally recurrence of renal cell carcinoma was defined as disease recurring in the remnant kidney, renal fossa, adjacent abdomen, ipsilateral adrenal and retroperitoneal lymph nodes. RESULTS: In the study, 81 patients were finally included, of whom 43 were initially treated in our hospital and 38 were initially treat in other centers. Partial nephrectomy (PN) was performed for 38 cases (26 in our hospital and 12 in other hospitals) as initial treatment and radical nephrectomy (RN) was conducted for the remnant 43 cases (17 in our hospital and 26 in other hospitals). Overall median recurrence time was 26 months (range: 3-164 months), in which 26 months (range: 3-55 months) for PN cases and 30 months (range: 4-164 months) for RN cases (P=0.009). Sixty-nine patients had single site recurrence, including remnant kidney (n=29), renal fossa (n=20), abdomen (n=4), ipsilateral lymph nodes (n=5), ipsilateral adrenal (n=11), while 12 patients had multiple sites recurrence. Seventy-eight patients were managed by complete surgical resection, while three patients were managed by radiofrequency ablation. Postoperative pathological diagnoses included clear cell carcinoma (n=72), papillary renal cell carcinoma (n=8, 7 cases with type 1, 1 case with type 2) and Xp11 translocation/TFE3 gene fusion renal cell carcinoma (n=1). Complete pathologic information of the initial surgery could be extracted from 43 patients who were initially treated in our hospital. Seventeen patients with initial radical nephrectomy were staged as T1a (n=4), T1b (n=2), T2a (n=1), T3a (n=8), and T3b (n=2). Twenty-six patients with initial partial nephrectomy were staged as T1a (n=18), T1b (n=7), and T3a (n=1). For PN cohort, the patients with T1a stage disease had longer median recurrence time than those with beyond T1a stage disease, and the difference was significant (29 months vs. 18 months, P=0.041). At the end of the follow-up, 58 patients were alive, 4 died and 19 lost the follow-up. Overall, 3-year and 5-year disease free survival rates were 81.9%, and 53.6%, respectively. CONCLUSION: The present research reported a large-scale single central experience of locally recurrent renal cell carcinoma. The recurrence time of the PN group is shorter than that of the RN group. For patients after PN surgery, median recurrence time is longer for patients with T1a stage tumor when compared with those with stage beyond T1a. Patients can obtain relative long-term survival after complete secondary surgery resection.

[Comparison of efficacy and safety between two different methods of nephroureterectomy in two centers].

OBJECTIVE: To compare the efficacy and safety of complete transperitoneal laparoscopic nephroureterectomy (CTNU) and traditional retroperitoneoscopic nehroureterectomy (TRNU) for the management of upper urinary tract urothelial carcinoma(UTUC). METHODS: We retrospectively collected the clinical data of UTUC patients who underwent CTNU or TRNU surgery from January 2011 to December 2018 in Peking University First Hospital and Fujian Provincial Hospital, and compared the clinical characteristics, perioperative parameters, and follow-up results between the CTNU and TRNU surgeries. RESULTS: Finally, a total of 266 cases were included, with 94 cases in the CTNU group and 172 cases in the TRNU group. The proportion of left side lesions was bigger in TRNU group when compared with CTNU group (P<0.05). No significant differences were observed in clinical characteristics, such as age, gender, body mass index (BMI), American society of anesthesiologists score (ASA score) and tumor laterality. All surgery procedures were completed. The vascular resparing was performed by reason that left arteria renalis was injured accidently during surgical operation in one case of TRNU group. No serious complications were observed in both CTNU and TRNU groups. In CTNU group, operating time was (202.9±76.7) min, estimated blood loss was (68.4±73.3) mL, drainage duration was (3.9±1.5) d, drainage volume was (181.7±251.5) mL, and postoperative hospital stay was (7.8±4.1) d. In TRNU group, operating time was (203.5±68.7) min, estimated blood loss was (130.2±252.1) mL, drainage duration was (4.3 ±1.6) d, drainage volume was (179.1±167.5) mL, and postoperative hospital stay was (8.2±3.7) d. The estimated blood loss in CTNU group was significantly less than that in TRNU group (P=0.005).The median follow-up time was 39 months (range: 1-88 months). The 5-year overall survival rate (OS), cancer specific survival rate (CSS), intra-vesical recurrence free survival rate (IvRFS), disease free survival rate (DFS) of CTNU group was 75.6%, 86.9%, 73.8%, 57.5%, respectively. The OS, CSS, IvRFS and DFS of TRNU group was 66.3%, 83.5%, 75.9%, 58.6%, respectively.No significant differences were observed in the OS, CSS, IvRFS and DFS between the CTNU and TRNU groups. CONCLUSION: CTNU technique is a safe and effective surgical option, and further prospective randomized controlled trial is needed for further evaluation.

Mutations in human TBX5 [corrected] cause limb and cardiac malformation in Holt-Oram syndrome.

Holt-Oram syndrome is characterized by upper limb malformations and cardiac septation defects. Here, we demonstrate that mutations in the human TBX5 gene underlie this disorder. TBX5 was cloned from the disease locus on human chromosome 12q24.1 and identified as a member of the T-box transcription factor family. A nonsense mutation in TBX5 causes Holt-Oram syndrome in affected members of one family; a TBX5 missense mutation was identified in affected members of another. We conclude that TBX5 is critical for limb and heart development and suggest that haploinsufficiency of TBX5 causes Holt-Oram syndrome.

Mutations in human TBX3 alter limb, apocrine and genital development in ulnar-mammary syndrome.

Ulnar-mammary syndrome is a rare pleiotropic disorder affecting limb, apocrine gland, tooth and genital development. We demonstrate that mutations in human TBX3, a member of the T-box gene family, cause ulnar-mammary syndrome in two families. Each mutation (a single nucleotide deletion and a splice-site mutation) is predicted to cause haploinsufficiency of TBX3, implying that critical levels of this transcription factor are required for morphogenesis of several organs. Limb abnormalities of ulnar-mammary syndrome involve posterior elements. Mutations in TBX5, a related and linked gene, cause anterior limb abnormalities in Holt-Oram syndrome. We suggest that during the evolution of TBX3 and TBX5 from a common ancestral gene, each has acquired specific yet complementary roles in patterning the mammalian upper limb.

Lysergic acid diethylamide: role in conversion of plasma tryptophan to brain serotonin (5-hydroxytryptamine).

Injections of D-lysergic acid diethylamide decrease the turnover rate of 5-hydroxytryptamine of rat brain, as measured from the conversion of (14)C-tryptophan into (14)C-5-hydroxytryptamine. The 2-bromolysergic acid diethylamide given in doses fivefold greater than those of lysergic acid diethylamide fails to change the rate of (14)C-tryptophan conversion into (14)C-5-hydroxytryptamine. The effect of D-lysergic acid diethylamide is discussed with regard to its action on brain serotonergic neurons and its psychotomimetic effects.

Sensorimotor encoding by synchronous neural ensemble activity at multiple levels of the somatosensory system.

Neural ensemble processing of sensorimotor information during behavior was investigated by simultaneously recording up to 48 single neurons at multiple relays of the rat trigeminal somatosensory system. Cortical, thalamic, and brainstem neurons exhibited widespread 7- to 12-hertz synchronous oscillations, which began during attentive immobility and reliably predicted the imminent onset of rhythmic whisker twitching. Each oscillatory cycle began as a traveling wave of neural activity in the cortex that then spread to the thalamus. Just before the onset of rhythmic whisker twitching, the oscillations spread to the spinal trigeminal brainstem complex. Thereafter, the oscillations at all levels were synchronous with whisker protraction. Neural structures manifesting these rhythms also exhibited distributed spatiotemporal patterns of neuronal ensemble activity in response to tactile stimulation. Thus, multilevel synchronous activity in this system may encode not only sensory information but also the onset and temporal domain of tactile exploratory movements.

Structural organization of the synaptic exocytosis core complex.

Syntaxin, vesicle-associated membrane protein (VAMP), and synaptosome-associated protein of 25 kDa (SNAP-25) form a ternary "core complex" central to the process of synaptic vesicle docking and fusion. Several lines of evidence support the hypothesis that the proteins assemble in a coiled-coil structure, but the alignment of alpha helices in this coil and the overall conformation of the coil are unknown. We employ the technique of fluorescence resonance energy transfer (FRET) to investigate the alignment between syntaxin and VAMP. With the acceptor probe coupled to the amino-terminal end of the VAMP coiled-coil domain, the donor probe fluorescence is quenched to a greater extent when it is on the amino-terminal end of the syntaxin H3 domain than when it is on the carboxy-terminal end. The data indicate that syntaxin and VAMP bind primarily in a parallel arrangement and suggest a coiled-coil structure that is bent rather than fully extended. We propose a model in which binding of SNAP receptor (SNARE) protein coiled-coil domains helps drive vesicle fusion.

Distinct domains of syntaxin are required for synaptic vesicle fusion complex formation and dissociation.

Membrane fusion resulting in neurotransmitter secretion forms the basis of neural communication. Three multimeric complexes of the protein syntaxin are important in this process: syntaxin and n-sec1; syntaxin, VAMP, and SNAP-25; and syntaxin, VAMP, SNAP-25, alpha SNAP, and NSF (20S complex). In this report, we demonstrate that unique, yet overlapping, domains of syntaxin are required to form these complexes. The formation of higher order heteromultimers has a set of structural requirements distinct from those required for dimeric interactions. Dissociation of the 20S complex by NSF following ATP hydrolysis requires amino-terminal regions of syntaxin that are outside of the binding domains for the 20S constituent proteins. These data are consistent with the hypothesis that conformational changes in syntaxin, resulting from protein-protein interactions and ATP hydrolysis by NSF, mediate neurotransmitter release.

Detection of a protein-acetaldehyde adduct in the liver of rats fed alcohol chronically.

We report here the formation in vivo of a protein-acetaldehyde adduct (protein-AA) in liver when rats were fed alcohol chronically. This chemically modified protein was demonstrated by electroimmunotransblot technique and with rabbit polyclonal antibodies that recognize acetaldehyde adduct as an epitope (i.e., both anti-hemocyanin-AA IgG and anti-myoglobin-AA IgG). It has a molecular weight of 37,000. It can be detected in the liver of rats fed the alcohol-containing American Institute of Nutrition 1976 liquid diet for only 1 wk. Since the protein profiles of soluble hepatic proteins from alcohol-fed and control rats were identical on SDS-PAGE, the peroxidase-positive band demonstrated by electroimmunotransblot was most likely not a new protein synthesized de novo. Borohydride reduction was not necessary to stabilize this protein-AA. Intraperitoneal injections of ethanol (2 g/kg body wt) at 8-h intervals to rats over a 24-h period did not produce any detectable protein-AA in the liver. Incubation of the liver homogenate from a control liver with acetaldehyde without sodium cyanoborohydride for 4 h also failed to generate any protein-AA. Therefore, the formation of the 37-kD protein-AA in vivo reported here is dependent on chronic alcohol consumption.

Serum low density lipoprotein of alcoholic patients is chemically modified in vivo and induces apolipoprotein E synthesis by macrophages.

This work was carried out to investigate the effect of alcohol drinking on serum LDL. Agarose gel electrophoresis showed that LDL samples from alcoholic patients without serious liver disease were more negatively charged and moved faster toward the cathode than LDL from nondrinking control subjects. Rabbit antibodies raised by using keyhole limpet hemocyanin modified in vitro by 4-hydroxynonenal or by acetaldehyde as immunogens reacted more strongly with patients' LDL than with control LDL, indicating the presence of oxidatively modified epitopes and acetaldehyde adducts in alcoholic patients' LDL. LDL of alcoholic patients has decreased vitamin E contents. The electromobility of LDL decreased after abstinence from alcohol and returned to normal in 2 wk, but this was not accompanied by a significant increase in its vitamin E contents. When incubated with mouse peritoneal macrophages, patients' LDL induced apolipoprotein E secretion by threefold over control LDL with a concomitant increase in cellular cholesterol. Our results thus demonstrate that LDL of alcoholic patients has lower vitamin E content, is chemically modified in vivo, and exhibits altered biological function. These changes in heavy alcoholic drinkers may render LDL more atherogenic and thereby may counter the antiatherosclerosis effects of moderate alcohol consumption.

Secretion of the newly synthesized cholesterol by rat hepatocytes in primary culture.

We used monolayer cultured rat hepatocytes as an experimental model to study the secretion of the newly synthesized cholesterol by the liver. Cellular cholesterol was labeled by exposing cultured hepatocytes to [14C]acetate prior to the study of secretion. Secretion of the newly synthesized cholesterol was measured by extracting cholesterol in the culture medium and assaying for the radioactivity of [14C]cholesterol. We found that: (a) cultured hepatocytes could secrete newly synthesized cholesterol in serum-free medium; (b) secreted [14C]cholesterol was bound to macromolecule(s) and the secretion rate was not affected by cycloheximide for up to 5 h; (c) serum added to the culture medium greatly enhanced hepatic cholesterol secretion; (d) serum high-density lipoproteins were most effective, lipoprotein-deficient serum (d greater than 1.21) less effective in stimulating cholesterol secretion, whereas low-density and very-low-density lipoproteins had little effect; (e) when the serum-free culture medium was fractionated by ultracentrifugation, a major portion of the secreted [14C]cholesterol was found in the high-density lipoprotein fraction; (f) part of the medium [14C]cholesterol also turned up in the high-density lipoprotein fraction when lipoprotein-deficient serum was added as the acceptor; (g) secreted [14C]cholesterol was found only in free form, although some of the cellular [14C]cholesterol was found as esters.

Effect of dexamethasone on 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity and cholesterol synthesis in rat liver.

Dexamethasone increases reductase activity in cultured liver cells after a lag period of 2 h. The increases of activity are linear from 10(-9) to 10(-5) M dexamethasone, the maximum responses ranging from 2- to 4-fold. The increased reductase activity after dexamethasone treatment is not due to a change of the state of phosphorylation/dephosphorylation of the enzyme nor to an increase of cytosolic activating factor(s) for the reductase. Cholesterol synthesis, measured by incorporation of either [14C]acetate or 3H2O, increases 3-fold after dexamethasone (10(-6) M) treatment, as does the hydroxymethylglutaryl-CoA reductase activity, confirming that this enzyme is rate-controlling for cholesterol synthesis in cultured liver cells as it is in vivo. Dexamethasone (10 micrograms/100 g rat), given after onset of the light cycle, increases reductase activity over control rats at the nadir of the circadian cycle of this enzyme. When given after onset of the dark cycle, dexamethasone does not increase reductase activity over controls at the peak of their circadian cycle. Thus, physiologic doses of glucocorticoids partially reverse the decline in reductase activity due to the circadian rhythm.

Increase of resting levels of superoxide anion in the whole blood of patients with decompensated liver cirrhosis.

The aim of this study is to investigate the relationship between the resting level of superoxide anion (O2.) and liver cirrhosis (LC). The resting levels of superoxide anion in the whole blood of healthy controls and patients with compensated or decompensated LC were measured, by an ultra-sensitive chemiluminescence (CL) analyzer and lucigenin amplification. The assay system can be performed in the absence of leukocyte isolation and stimulant administration. The results showed that the blood CL levels of compensated cirrhotic patients (381.0 +/- 201.5 counts/10 s, mean +/- SD, n = 24) were similar to that of healthy controls (467.9 +/- 299.5 counts/10 s, n = 24). However, the blood CL levels of decompensated cirrhotic patients (2083.5 +/- 1462.4 counts/10 s, n = 24) were significantly greater than that of healthy controls and patients with compensated LC (both p < .001, Student's t-test). The correlation analysis revealed that the blood CL levels in cirrhotic patients were significantly correlated with serum concentrations of albumin (r = -0.65, p < .001) and total bilirubin (r = +0.42, p < .005). However, there was no significant correlation between the blood CL levels and serum levels of transaminases (GOT and GPT). These results suggest that blood levels of superoxide of decompensated cirrhotic patients were greater than those of healthy controls or compensated cirrhotic patients. Moreover, the increase of blood levels of superoxide in decompensated cirrhotic patients is related to the impairment of liver function but not to the inflammation.

Origin, distribution, and morphology of galaninergic fibers in the rodent trigeminal system.

The neuropeptide galanin (Gal) is found throughout the central nervous system. Of particular interest is the fact that Gal is present within the majority of noradrenergic locus coeruleus (LC) neurons. However, very few, if any, Gal-immunoreactive fibers have been identified in many of the major efferent targets of LC, including sensory neocortex and dorsal thalamus. The goal of the present study was to examine the Gal fiber innervation of the rodent trigeminal somatosensory system and its connection to the LC. Our results show that at least two different morphological profiles of Gal-immunoreactive fibers are present within relay nuclei along the ascending trigeminal pathway. Numerous small caliber Gal-immunoreactive fibers with bouton-like swellings were noted within the barrel cortex, the ventroposterior medial (VPM) nucleus, the posterior medial (POm) nucleus, the zona incerta (ZI), the reticular nucleus (nRT) of the thalamus, and the principal (PrV) and spinal (SpV) nuclei of the trigeminal complex. Immunoreactive fibers were prevalent in, but not restricted to, layer I of the barrel cortex. Within the somatosensory thalamus, the density of Gal-immunoreactive fibers was higher in POm than in VPM. Laminae I and II of SpV and the nRT and ZI also contained dense, large-diameter Gal-immunoreactive fibers. These large-diameter Gal-immunoreactive fibers did not co-contain dopamine beta-hydroxylase (DBH). In contrast, virtually every small-caliber Gal-immunoreactive fiber colocalized with DBH. To determine whether Gal-immunoreactive fibers originated from LC, we combined immunohistochemical procedures with fluorescent tracing techniques. After retrograde tracer injections into several trigeminal relay nuclei, we observed that approximately 50% of the labeled LC neuronal population was immunoreactive for Gal. Our results suggest an extensive Gal-immunoreactive fiber innervation of the rodent trigeminal system, much of which may originate from LC neurons in the brainstem.

Projection patterns from the raphe nuclear complex to the ependymal wall of the ventricular system in the rat.

The goal of the present study was to characterize the anatomical and neurochemical relationships that the raphe nuclear complex maintains with respect to lateralized and centralized components of the ventricular system. From this investigation, we 1) determined the ipsilateral vs. contralateral distribution of raphe efferents to the ependymal wall of the lateral ventricle, 2) assessed the degree of collateralization of individual ependymal projection neurons to other sites along the ventricular path, 3) compared the topography of raphe neurons that project to the ventricular lining as well as the lumen of the fourth and lateral ventricles, and 4) evaluated the neurochemical identity of raphe neurons that innervate the ventricular system. After tracer injections into the lateral ventricle, labeled cells were distributed evenly on both sides of the midline in the dorsomedial subregion of the intermediate dorsal raphe nucleus. Further rostrally, labeled cells were clustered bilaterally above the medial longitudinal fasciculi and extended into the median raphe nucleus. Injections that involved the ependymal wall of the lateral ventricle resulted in prominent ipsilateral labeling within the dorsal raphe nucleus, just ventral to the cerebral aqueduct. Most of the labeled cells in this latter group had collateral projections to other sites along the ventricular path. Most of the ventricle projection cells contained serotonin but not nicotinamide adenine dinucleotide phosphate diaphorase. These findings indicate that the raphe nuclear complex is topographically organized with respect to the ventricular system. Selected subsets of serotoninergic dorsal raphe neurons may influence discrete segments of the ventricular system independently as well as coordinate functions throughout the system through axon collaterals to other sites along the ventricular neuraxis.

Topographic organization and neurochemical identity of dorsal raphe neurons that project to the trigeminal somatosensory pathway in the rat.

The primary goals of this study were to: 1) examine the distribution of neurons within the dorsal raphe (DR) nucleus that project to cortical and subcortical sites along the trigeminal somatosensory pathway in rat; 2) determine the extent to which different regions within this ascending sensory system receive collateral projections from the same DR neuron; and 3) identify the putative transmitters contained within these DR projection neurons. Long-Evans hooded rats received pressure injections of various combinations of retrograde fluorescent tracers; into the whisker-related regions of the primary somatosensory cortex (barrel field cortex [BC]), ventral posterior medial thalamus (VPM), and principal nucleus of the trigeminal complex (PrV). The distribution of retrogradely labeled neurons within the DR was examined by fluorescence microscopy. The major finding was that cortically projecting neurons were located within the midline regions of the rostral portion of the DR, whereas cells projecting to subcortical trigeminal somatosensory structures were distributed bilaterally in the lateral wing regions of the DR as well as in the midline portions of the nucleus. Single neurons that send axon collaterals to multiple cortical and subcortical trigeminal somatosensory targets were observed in the dorsomedian and ventromedian regions of the DR. DR neurons that projected to cortical and subcortical sites contained serotonin but not tyrosine hydroxylase, the marker enzyme for catecholamine transmitters. Taken together, these findings provide further evidence of neurochemical specificity and functional anatomical organization within the DR efferent projection system.

Lateralization and functional organization of the locus coeruleus projection to the trigeminal somatosensory pathway in rat.

The primary goals of this study were to (1) examine the distribution of locus coeruleus (LC) neurons, which project to cortical and subcortical sites along the trigeminal somatosensory pathway in rats, and (2) determine the extent to which different regions within this ascending sensory system receive collateral projections from the same LC neuron. Long-Evans hooded rats received unilateral pressure injections of different combinations of retrograde fluorescent tracers into whisker-related regions of primary (SI) and secondary (SII) somatosensory cortices, the ventrobasal (VB) and posterior group (POm) nuclei of the thalamus, and the principalis nucleus of the trigeminal complex (PrV). Coronal sections (40-100 microm) through the LC were examined by fluorescence microscopy, and the distribution of retrogradely labeled cells was recorded. The major finding was that whisker-related regions of the cortex receive efferent projections from neurons concentrated in the caudal portion of the ipsilateral LC, whereas subcortical trigeminal somatosensory structures receive bilateral input from both LC nuclei. Despite the bilateral nature of the LC projection to subcortical sites, the majority of LC efferents to VB and POm thalamus originate in the ipsilateral LC nucleus, whereas projections to PrV originate primarily from the contralateral LC. An additional finding was that a relatively large proportion of LC cells, which project to a single somatosensory structure, also send axon collaterals to other relay sites along the same ascending somatosensory pathway. Taken together, these results suggest that the LC-noradrenergic system maintains a more selective relationship with functionally related efferent targets than has been previously appreciated.

Effects of isoflavones on alcohol pharmacokinetics and alcohol-drinking behavior in rats.

Puerarin, daidzin, and daidzein are 3 major isoflavonoid compounds isolated from Pueraria lobata, an edible vine used widely in China for various medicinal purposes. We studied the antiinebriation and the antidipsotropic effects of these antioxidants in rats. Daidzin and daidzein shortened alcohol-induced sleep time (loss of righting reflex) in rats that were given ethanol intragastrically but not in those given ethanol intraperitoneally. When daidzin was given to animals intragastrically with the ethanol solution, the blood alcohol concentration (BAC) was found to peak later and be lower than in control rats that were given only the ethanol solution. BACs also receded more slowly if daidzin was fed to the animals. None of the 3 isoflavonoid compounds administered orally affected liver alcohol dehydrogenase or aldehyde dehydrogenase activities, as was reported for intraperitoneal administration. Further experiments indicated that the suppression of the BAC by daidzin was due mainly to delay of stomach emptying. All 3 compounds suppressed voluntary alcohol consumption in alcohol-preferring rats. The decrease in alcohol consumption was accompanied by an increase in water intake, so that the total volume of liquid consumed daily remained unchanged. Daily food consumption and body weight gain were not affected. Alcohol preference returned to baseline levels after the isoflavonoids were discontinued. We postulate that the suppression of alcohol reinforcement produced by these compounds is mediated centrally in the brain reward pathway.

N-Terminal dipeptides of D(-)-penicillamine as sequestration agents for acetaldehyde.

Since acetaldehyde (AcH), a toxic oxidation product of ethanol, may play an etiologic role in the initiation of alcoholic liver disease, we had earlier pioneered the development of beta, beta-disubstituted-beta-mercapto-alpha-amino acids as AcH-sequestering agents. We now report the synthesis of a series of N-terminal dipeptides of D(-)-penicillamine, prepared from the synthon 3-formyl-2,2,5,5-tetramethylthiazolidine-4S-carboxylic acid (3), a cyclized N-protected derivative of D(-)-penicillamine. These dipeptides were equally or more effective than penicillamine in trapping AcH in a cell-free system. In experiments using a hepatocyte culture system, two of the dipeptides, D-penicillamylglycine (6a) and D-penicillamyl-beta-alanine (6d), at 1/20 the molar concentration of ethanol, lowered the concentration of ethanol-derived AcH by 79% and 84%, respectively, at 2 h. The presence of cyanamide (an inhibitor of aldehyde dehydrogenase) in the incubation medium resulted in a 45-fold increase in ethanol-derived AcH; nevertheless, dipeptides 6a and 6c (D-penicillamyl-alpha-aminoisobutyric acid) were able to reduce this AcH level by approximately one-third.

Immunohistochemical demonstration of neuron-specific enolase and microtubule-associated protein 2 in reactive astrocytes after injury in the adult forebrain.

Transformation of normal resting astrocytes to reactive astrocytes in the adult brain after injury has been well documented. Using double immunofluorescent labeling methods, we report that astrocytes in both the ischemically damaged and the retrogradely/anterogradely degenerating forebrain nuclei express not only the glial cell markers glial fibrillary acidic protein and vimentin, but also the neuronal markers neuron-specific enolase and microtubule-associated protein 2. Since these neuronal markers are expressed in glial precursor cells, these results suggest that one of the characteristic responses of astrocytes in the adult brain after injury may be re-expression of fetal trait(s) of early differentiating glial cells/neurons.