Efficacy of Kanglaite against radiotherapy-induced mucositis in head and neck cancer, a phase II trial.

PURPOSE: To explore the potential protective effect of Kanglaite injection against radiotherapy-induced mucositis in patients with head and neck cancer. PATIENTS AND METHODS: This was an open-label, single-arm, and phase II trial. The primary endpoint was the incidence of grade 3-4 radiation-induced mucositis. The secondary endpoints were hematological toxicity, non-hematological toxicity, nutritional status, and quality of life. All patients received 20g Kanglaite daily concurrently with radiotherapy. RESULTS: The data of 46 patients were available for analysis. The incidence rates of grade 3 mucositis, pain, dysphagia, and neutropenia were 10.9%, 2.2%, 10.9%, and 6.5%, respectively, while the incidence of grade 4 acute toxicities was zero. The rate of opioid use was 2.2%. Radiotherapy dose reduction was 2.2% and no irradiation field was modified. The nutritional supports were oro-enteral nutritional supplements (13.0%), TPN (10.9%), and feeding tubes (0%) during radiotherapy. After radiotherapy, 52.2% of patients lost weight, and the weight loss was <10%. The mean pain score in the QLQ-H&N35 and QLQ-C30 was <50. Patients had nearly normal physical, emotional, and cognitive functions. CONCLUSIONS: A low incidence of grade 3-4 radiation-induced mucositis and no severe acute toxic events, with favorable nutritional status and quality of life, were observed in cancer patients after Kanglaite injection. Our findings highlight the need for a prospective, multicenter, and randomized study to investigate the effect of Kanglaite injection on the reduction of radiation-induced mucositis in patients with head and neck cancer.

Neuroprotective effect of gastrodin in methamphetamine-induced apoptosis through regulating cAMP/PKA/CREB pathway in cortical neuron.

OBJECTIVE: Methamphetamine (MA) abuse induces neurotoxicity and causes neuronal cell apoptosis. Gastrodin is a traditional Chinese herbal medicine used for the treatment of nerve injuries, spinal cord injuries, and some central nervous system diseases as well. The present study investigated the neuroprotective effects of gastrodin against MA-induced neurotoxicity in neuronal cells and its potential protective mechanism. METHODS: The primary cortex neuronal culture was divided into four groups (control group, MA group, MA + gastrodin group, and MA + gastrodin + small interfering RNA group). The neurotoxicity of MA was assessed by detecting apoptotic cells by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling assay and cell viability by cell counting kit 8 (CCK-8) method, the Tuj1-positive cells and the average axonal length were detected by immunofluorescence, and the expressions of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-response element-binding (CREB), and brain-derived neurotrophic factor (BDNF) proteins were detected by Western blot. RESULTS: The results of CCK-8 assay showed that 0.5 mM MA was an optimal concentration that induced neurotoxicity (p < 0.01). Pretreatment with 25 mg/L gastrodin exerted maximum protective effects on neuronal cells. The expression levels of cAMP, PKA, phosphorylated PKA, CREB, phosphorylated CREB, and BDNF proteins were decreased in the MA group, and pretreatment with gastrodin upregulated the expression levels of these proteins (p < 0.01). The expressions of PKA and CREB proteins showed no significant changes in the control group, MA group, and gastrodin group. Compared the MA + gastrodin + small interfering RNA group with MA + gastrodin group, the Tuj1-positive cells and the average axonal length were decreased significantly, while the number of apoptotic cells was increased (p < 0.05). CONCLUSION: Gastrodin has neuroprotective effects against MA-induced neurotoxicity, which exerts neuroprotective effects via regulation of cAMP/PKA/CREB signaling pathway and upregulates the expression of BDNF.

Midline thalamic region: widespread excitatory input to the entorhinal cortex and amygdala.

The midline thalamus has a role in memory formation and has well described projections to multiple limbic sites including the hippocampus, amygdala, and entorhinal cortex. Stimulation of this region evokes excitatory responses in the CA1 region of the hippocampus, but nothing is known about the nature of thalamic influence on other limbic sites such as the entorhinal cortex and the amygdala. In this study we electrically stimulated the midline thalamus in anesthetized rats to determine whether responses could be evoked in the amygdala or entorhinal cortex. In addition we examined the distribution of the responses within the target regions as well as the effect of short interval paired or high-frequency tetanizing stimulation. We found reproducible responses in the entorhinal cortex and the amygdala with a distribution of responses that matched the described synaptic input from the thalamus. In addition, high-frequency stimulation induced a consistent long-term potentiation in the two sites. Paired stimulation resulted in depression of the test response in the amygdala, but a facilitation in the entorhinal cortex. These findings indicate that the midline has a significant monosynaptic excitatory influence in the amygdala and the entorhinal cortex. Combined with the previous work in the hippocampus, this study suggests that the midline thalamus plays a significant role in limbic physiology and may serve to synchronize activity in this system.

Thalamic excitation of hippocampal CA1 neurons: a comparison with the effects of CA3 stimulation.

CA1 is the major output area for the hippocampus, and current evidence shows that it is excited primarily from ipsilateral and contralateral CA3 pyramidal cells in the rat. Direct connections from the midline thalamic nuclei to the hippocampus have been described anatomically, but the physiological role of these connections has not been reported until the recent observation that these inputs may have a mild excitatory effect (subthreshold for population spikes). In this study, we report a more powerful excitatory effect of thalamic stimulation on the response of the CA1 neurons in the urethane-anesthetized rat. Electrical stimulation to the midline thalamus induced responses similar to responses from stimulation of the contralateral hippocampus (CA3), with well-developed field excitatory postsynaptic potentials and large population spikes. The latency of the CA1 response suggested that the thalamic connection was monosynaptic, and there was a laminar CA1 response profile that depended on the site of stimulation (contralateral CA3 or thalamus). In an initial examination of possible differences in the physiological effects of these two pathways on the CA1 region, we tested both sites for long-term potentiation of CA1, for the effects of repetitive stimulation on CA1 responses (e.g., possible augmenting responses) and for the effect of paired-pulse stimulation. In these three measures, there were clear and statistically significant differences between the effects of CA3 and thalamic stimulation on CA1 responses. This study demonstrates that the well-described thalamic connection to the hippocampus allows for the direct and powerful excitation of the CA1 region. This thalamohippocampal connection bypasses the trisynaptic/commissural pathway that has been thought to be the exclusive excitatory drive to CA1. In addition, preliminary data indicate that the thalamus and CA3 inputs have different physiological effects on CA1 pyramidal cells.

Structure and evolution of Cyclops: a novel giant retrotransposon of the Ty3/Gypsy family highly amplified in pea and other legume species.

We characterized a novel giant Gypsy-like retrotransposon, Cyclops, present in about 5000 copies in the genome of Pisum sativum. The individual element Cyclops-2 measures 12 314 bp including long terminal repeats (LTRs) of 1504 bp and 1594 bp, respectively, showing 4.1% sequence divergence between one another. Cyclops-2 carries a polypurine tract (PPT) and an unusual primer binding site (PBS) complementary to tRNA-Glu. The element is bounded by 5 bp target site duplications and harbors three successive internal regions with homology to retroviral genes gag (424 codons) and pol (1382 codons) and an additional open reading frame (423 codons) of unknown function indicating the element's potential capacity for gene transduction. The pol region contains sequence motifs related to the enzymes protease, reverse transcriptase, RNAse H and integrase in the same typical order (5'-PR-RT-RH-IN-3') known for retroviruses and Gypsy-like retrotransposons. The reading frame of the pol region is disrupted by several mutations suggesting that Cyclops-2 does not encode functional enzymes. A phylogenetic analysis of the reverse transcriptase domain confirms our differential genetic assessment that Cyclops from pea is a novel element with no specific relationship to the previously described Gypsy-like elements from plants. Genomic Southern hybridizations show that Cyclops is abundant not only in pea but also in common bean, mung bean, broad bean, soybean and the pea nut suggesting that Cyclops may be an useful genetic tool for analyzing the genomes of agronomically important legumes.

Five identical intron positions in ancient duplicated genes of eubacterial origin.

In 1985 Cornish-Bowden wrote "although there is now much to suggest that introns are an ancient relic of primordial genes, convincing proof must await the discovery of clearly corresponding intron arrangements in genes that arose by duplication before the separation of prokaryotes and eukaryotes". Genes for chloroplast and cytosolic glyceraldehyde-3-phosphate dehydrogenases of eukaryotes are descendants of an ancient gene family that existed in the common ancestor of extant eubacteria. During eukaryotic evolution, both genes were transferred to the nucleus from the antecedents of present-day chloroplasts and mitochondria, respectively. Here we report the discovery of five spliceosomal introns at positions that are precisely conserved between nuclear genes for this chloroplast/cytosol enzyme pair. These data provide strong evidence in favour of the 'introns early' hypothesis, which proposes that introns were present in the earliest cells, consistent with the idea that introns facilitated the assembly of primordial genes by accelerating the rate of exon shuffling.

Intracellular study of electrophysiological features of primate spinothalamic tract neurons and their responses to afferent inputs.

1. Intracellular recordings were made from 43 spinothalamic (STT) neurons in the lumbosacral region of the spinal cord in anesthetized macaque monkeys. The antidromic responses of these neurons to electrical stimulation of the ventral posterior lateral (VPL) nucleus of the thalamus were examined, and orthodromic responses to electrical stimulation of the sural nerve or to mechanical stimulation of hindlimb skin were recorded to study the electrophysiological features of these neurons and their responses to afferent inputs. 2. The resting membrane potential of the neurons ranged from -26 to -70 mV and the antidromic latency from 2.3 to 9.1 ms. Three of the neurons were located in lamina 1 and were recorded so briefly that only antidromic and spontaneous activity could be studied. The rest of the neurons were located in laminae III-V and were of the wide-dynamic-range (WDR) type. 3. The antidromic action potentials recorded in the somas of STT neurons typically showed a fast rising phase and a short initial segment-somadendritic (IS-SD) delay. After repetitive antidromic stimulation, a progressive elongation of the IS-SD delay, widening of the spike, and failure of the SD spike were observed. 4. The afterpotential of the antidromic action potential consisted of a fast afterhyperpolarization (AHPf) and sometimes a delayed depolarization (DD) and a slow afterhyperpolarization (AHPs). The amplitude and the duration of the AHPs were progressively increased when longer trains of stimuli were used. When the membrane potential was hyperpolarized, the amplitude of the AHPs decreased, suggesting an involvement of K+ and/or Cl- ions. However, the AHPs completely disappeared when the strength of stimulation was adjusted to a level just below the threshold for the axon, suggesting that it was unlikely that recurrent inhibition contributed to the AHPs. 5. The background activity of 32 STT neurons was analyzed. The membrane potential at which spikes were triggered in these neurons was around -42 mV. The width and the rise time of the spontaneous spikes were shorter than those of antidromic action potentials, although the maximum rate of rise was similar. The heights of the spontaneous spikes were slightly shorter than those of antidromic action potentials. 6. Three types of background activity have been observed. One type had a very low average spontaneous rate with a bursting firing pattern, consisting of a few spikes superimposed on a depolarization. This type of activity was seen mostly in lamina I neurons. The second type of activity had a moderate to high spontaneous rate with a fairly constant interval between spikes.(ABSTRACT TRUNCATED AT 400 WORDS)

Two forms of inhibition of spinothalamic tract neurons produced by stimulation of the periaqueductal gray and the cerebral cortex.

1. Recordings were made from the lumbosacral spinal cord in anesthetized macaque monkeys. The inhibitory effects of electrical stimulation of the periaqueductal gray (PAG) and the cerebral cortex or cerebral peduncle (CP) were tested and compared by recording 1) cord dorsum potentials evoked by stimulation of the sural nerve, 2) discharges recorded extracellularly, and 3) membrane potentials recorded intracellularly from spinothalamic tract (STT) neurons at rest (background activity) or in response to stimulation of the sural nerve. 2. Stimulation of the cortex or in the CP preferentially reduced the amplitude of the N1 and N2 waves of the cord dorsum potential evoked by stimulation of the sural nerve, without affecting the N3 wave. Stimulation of the PAG, on the other hand, reduced the amplitude of the N3 wave with little effect on the N1 and N2 waves. 3. The activity of 62 STT neurons was recorded extracellularly. Stimulation of the PAG or the cortex/CP inhibited nonpreferentially the responses of the neurons in the superficial laminae to all afferent inputs. On the other hand, stimulation of the PAG or the cortex/CP inhibited preferentially the responses of most STT neurons in deep layers of the dorsal horn to the small or large afferent input, respectively. 4. Thirty-five neurons were recorded intracellularly. The membrane potential of the neurons averaged -45.5 +/- 10.1 (SD) mV. All neurons were recorded in laminae III-VI; the neurons were of the wide-dynamic-range (WDR) type and had background activity. 5. The inhibitory effects of stimulation of the PAG were tested on all 35 neurons. In 32 of the neurons, stimulation of the PAG evoked a hyperpolarization. The background activity of the neurons was reduced (generally it completely ceased) by the hyperpolarization. In three neurons stimulation of the PAG did not evoke a hyperpolarization and the background activity of the neurons did not change. Nevertheless, the responses of these three neurons to afferent input were inhibited by stimulation in the PAG. 6. The inhibitory effects of stimulating the cortex and/or the CP were tested in 26 of the 35 neurons. Stimulation of the cortex and/or the CP evoked a hyperpolarization in all the neurons, although, in 10 of the 26 neurons, stimulation of the CP also evoked a depolarization. The hyperpolarization generally blocked the background activity of the neurons. 7. The effective stimuli in the PAG and the cortex/CP to evoke a hyperpolarization in STT neurons were short, high-frequency trains of pulses.(ABSTRACT TRUNCATED AT 400 WORDS)

Differential intron loss and endosymbiotic transfer of chloroplast glyceraldehyde-3-phosphate dehydrogenase genes to the nucleus.

Chloroplast glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is composed of two different subunits, GAPA and GAPB, which are encoded in the nucleus by two related genes of eubacterial origin. In the present work the genes encoding chloroplast GAPA and GAPB from pea have been cloned and sequenced. The gene for GAPB is split by eight introns. Two introns interrupt the region encoding the transit peptide and six are found within the region encoding the mature subunit, four of which are in identical or similar positions relative to genes for cytosolic GAPDH of eukaryotic organisms. As opposed to this, the gene encoding pea GAPA has only two introns in the region encoding the mature subunit. These findings strongly support the "intron early" hypothesis and suggest that the low number of introns in the gene for chloroplast GAPA is due to differential loss of introns during the streamlining period of the chloroplast genome following the GAPB/GAPA separation. We deduce from this that eubacteria and chloroplasts contained GT-AG introns until relatively recently and that the duplication event leading to the genes encoding GAPB and GAPA and their respective transit peptides occurred in the chloroplast progenitor prior to the successive transfer and functional reintegration of these genes into the nuclear environment. These conclusions imply that GAPA/GAPB transit peptides are of eubacterial origin.

Isolation of two new coumarin glycosides from Notopterygium forbesii and evaluation of a Chinese crude drug, qiang-huo, the underground parts of N. incisum and N. forbesii, by high-performance liquid chromatography.

From the ether extract of the underground part of Notopterygium forbesii, two new coumarin glycosides, bergaptol-O-beta-D-glucopyranoside and 6'-O-trans-feruloylnodakenin, were isolated along with known compounds including seven furanocoumarins, two dihydrofuranocoumarins, a sterol glucoside and two phenolic compounds. Analysis of their contents by high-performance liquid chromatography (HPLC) revealed that the underground part of N. forbesii contained large amounts of p-hydroxphenethyl anisate (0.7%), bergaptol glucoside (0.2%), nodakenin (2%) and 6'-O-trans-feruloylnodakenin (0.7%) and a lesser amount of notopterol (0.08%), while that of N. incisum contained a large amount of notopterol (1.2%) and less amounts of the others. The characteristic difference in chemical composition between the two species enabled us to identify the respective botanical sources of a Chinese crude drug, Qiang-huo derived from N. incisum and N. forbesii by HPLC.