[Significance of HPV and cell cycle related proteins in basaloid squamous cell carcinoma of the larynx].

Objective: To study the significance of HPV and cell cycle related proteins in basaloid squamous cell carcinoma (BSCC) of the larynx. Methods: Twenty-nine cases of laryngeal BSCC from Beijing Tongren Hospital from January 2005 to December 2011 were reviewed. HPV typing by polymerase chain reaction-reverse dot blot (PCR-RDB) and p53, Ki-67, p16, p21 and cyclin D1 expression by immunohistochemistry were performed. The relationship between these indicators, various pathologic parameters (TNM, tumor size, tumor site and lymph node metastasis) and HPV status was analyzed. Results: There were 27 male and 2 female patients. The median age was 62 years. Lymph node metastasis and supraglottic tumor location were slightly higher than that of "usual" SCC, but not statistically significant (P>0.05). HPV DNA was detected in 27.6% (8/29) of the laryngeal BSCC, and all were HPV16. The expression of HPV was not related to age, alcohol consumption, tumor stage and tumor size. p53 was expressed in 31.0%(9/29) of laryngeal BSCC, and these cases were more likely supraglottic and had lymph node metastases (P<0.05). p16 staining was seen in 24.1% (7/29) of laryngeal BSCC, and these cases showed slightly higher rate of lymph node metastasis compared to p16 negative cases. The expression rates of p21 and cyclinD1 were 27.6% (8/29) and 69.0%(20/29), respectively, which were not related to age, tumor size, stage, lymph node metastasis, smoking and drinking. There were only 3 p16+ /HPV+ cases, which showed higher p21 and Ki-67 index compared to the HPV negative group (P<0.05). Conclusion: Some laryngeal BSCC expresses HPV DNA, possibly indicating an association with HPV; but p16 expression is not a reliable indicator for HPV infection.

The role of dopamine receptors in ventrolateral orbital cortex-evoked anti-nociception in a rat model of neuropathic pain.

The present study examined the role of dopamine and D(1)-and D(2)-like dopamine receptors in ventrolateral orbital cortex (VLO)-evoked anti-hypersensitivity in a rat model of neuropathic pain, as well as the possible underlying mechanisms. Results showed that microinjection of apomorphine [(R(-)-apomorphine hydrochloride)], a non-selective dopamine receptor agonist, into the VLO attenuated spared nerve injury (SNI)-induced mechanical allodynia in a dose-dependent manner. This effect was completely blocked by the D(2)-like dopamine receptor antagonist S(-)-raclopride(+)-tartrate salt (1.5 microg), but was enhanced by the D(1)-like dopamine receptor antagonist SCH23390 (R(+)-SCH-23390 hydrochloride, 5.0 microg). The attenuating effect of apomorphine on mechanical allodynia was mimicked by application of the D(2)-like dopamine receptor agonist quinpirole [((-)-quinpirole hydrochloride, 0.5, 1.0, and 2.0 microg)]. In addition, microinjection of larger doses (10 and 20 microg) of SCH23390 into the VLO significantly attenuated allodynia. Furthermore, microinjections of GABA(A) receptor antagonists, bicuculline [(+)-bicuculline,(S), 9(R)] and picrotoxin (200 and 300 ng for both drugs), into the VLO attenuated mechanical allodynia. A small dose of bicuculline or picrotoxin (100 ng) resulted in increased quinpirole (0.5 microg)-induced anti-allodynia. In contrast, GABA(A) receptor agonists, muscimol hydrochloride (250 ng) or THIP [(2,5,6,7-retrahydroisoxazolo(5,4-c)pyridine-3-ol hydrochloride, 1.0 microg)], blocked quinpirole (2.0 microg)-induced attenuation. These results suggest that the dopaminergic system is involved in mediating VLO-induced anti-hypersensitivity, activation of D(2)-like dopamine receptors, and inhibition of D(1)-like receptors resulting in anti-hypersensitivity. In addition, the mechanisms of GABAergic disinhibition might be involved in D(2)-like receptor mediating effects in neuropathic pain.

Activation of mu-opioid receptors in thalamic nucleus submedius depresses bee venom-evoked spinal c-Fos expression and flinching behavior.

Previous studies have indicated that mu-opioid receptors in the thalamic nucleus submedius (Sm) are involved in descending antinociception in behavioral tests. The present study examined the effect of mu-opioid receptor activation in the Sm upon bee venom-evoked c-Fos expression in the spinal dorsal horn associated with flinching behavior, and determined whether the ATP-sensitive potassium channel (K-ATP channel) was involved in this effect in a rat model. A dilute bee venom solution, subcutaneously injected unilaterally into a rat hind paw pad, induced significant c-Fos expression in the lumbar spinal dorsal horn, which is associated with paw flinching behavior. This effect was depressed by microinjection of the mu-opioid receptor agonist [d-Ala2, N-MePhe4, Gly-ol5]-enkephalin (DAMGO) into the Sm, which was antagonized by pre-treatment with mu-receptor antagonist beta-funaltrexamine at the same Sm site. Further studies found that glibenclamide, a K-ATP channel inhibitor, also blocked DAMGO-induced inhibition. These results provide functional anatomic support for the involvement of Sm and mu-opioid receptors in the modulation of persistent inflammatory nociception, and suggest that these effects were produced by opening K-ATP channel and inhibiting neuronal activity. Together with previous studies, the inhibition of the neuronal activity induced by mu-opioid receptor activation may activate descending antinociceptive pathways through a GABAergic disinhibitory mechanism and depress the nociceptive information transmission at the level of the spinal cord.

The role of 5-HT receptor subtypes in the ventrolateral orbital cortex of 5-HT-induced antinociception in the rat.

The present study examined the involvement of 5-HT in the ventrolateral orbital cortex (VLO) on descending antinociception and determined which subtypes of 5-HT receptors mediated this effect. This study focused on the effects of 5-HT microinjection in the VLO of lightly anesthetized male rats on the radiant heat-evoked tail flick (TF) reflex, as well as the influence of 5-HT(1A), 5-HT(2), 5-HT(3), and 5-HT(4) receptor subtype antagonists on the effect of 5-HT. Results showed that 5-HT microinjection (2, 5, 10 microg, in 0.5 microl) into the VLO depressed the TF reflex in a dose-dependent manner. Pretreatment with 5-HT receptor antagonists (1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine hydrobromide (NAN-190), cyproheptadine hydrochloride (CPT) and 1-methyl-N-(8-methyl-8-azabicyclo[3.2.3]-oct-3-yl)-1H-indazole-3-carboxamide maleate salt (LY-278,584)), specific for 5-HT(1A), 5-HT(2) and 5-HT(3) receptors, respectively, partially reversed the 5-HT-evoked inhibition. In contrast, the 5-HT(4) receptor antagonist, 1-[2-[(methylsulfonyl)-amino]ethyl]-4-piperidinyl]methyl1-methyl-1H-indole-3-carboxylate (GR 113808), had no effect on the inhibition of 5-HT. Microinjections of NAN-190, CPT and LY-278,584 alone into the VLO had no effect on the TF reflex. These results suggest that 5-HT(1A), 5-HT(2) and 5-HT(3), but not 5-HT(4) receptors, are involved in mediating 5-HT-induced antinociception in the VLO. According to different properties and distribution patterns of the 5-HT receptor subtypes on neurons, the possible mechanism of 5-HT activation of the VLO-periaqueductal gray (PAG) descending antinociceptive pathway is discussed.

Spectrophotometric determination of uranium(VI) with 2-(3,5-dibromo-2-pyridylazo)-5-diethylaminophenol in the presence of anionic surfactant.

A highly sensitive method for spectrophotometric determination of uranium has been devised. The method is based on formation of a red-violet 1:2 (metal:ligand) complex from the reaction of uranium(VI) with 2-(3,5-dibromo-2-pyridylazo)-5-diethylaminophenol (3,5-diBr-PADAP) in the presence of an anionic surfactant, sodium lauryl sulphate. Its molar absorptivity is found to be 9.1 x 10(4)l.mole(-1).cm(-1). The absorbance is constant in the range pH 8.4-9.9 Beer's law is obeyed for 0-1.4 mug/ml concentrations of uranium. In the presence of DCTA the method is selective for uranium, and can be used for the determination of trace amounts of uranium in water samples.

Spectrophotometric determination of silver with 2-(3,5-dibromo-2-pyridylazo)-5-diethyl-aminophenol in the presence of anionic surfactant.

A sensitive and selective spectrophotometric method for silver has been established by reacting silver(I) with 2-(3,5-dibromo-2-pyridylazo)-5-diethylaminophenol (3,5-diBr-PADAP) in the presence of an anionic surfactant, sodium lauryl sulphate. The molar absorptivity is 7.7 x 10(4) l.mole(-1).cm(-1) at 570nm. The molar ratio of silver to 3,5-diBr-PADAP is 1:2. Beer's law is obeyed from 0.1 to 1 ppm of silver. With EDTA as masking agent, common ions do not interfere. The method has been applied to the determination of silver in waste water.