Human papillomavirus type 58 in Bowen's disease of the elbow

Human papillomavirus (HPV) can be detected in skin lesions of Bowen's disease, particularly on the fingers, and its genotype is associated with mucosal/genital types of HPV. We report herein an 85-year-old woman who had HPV-associated Bowen's disease on her elbow. HPV-58 DNA was detected in the lesion by polymerase chain reaction with restriction fragment length polymorphism and by Southern blot hybridization. In situ hybridization revealed numerous hybrid cells in the nuclei of the upper epidermis and stratum corneum of Bowen's disease. A high-risk type of mucosal HPV-58 DNA is associated with Bowen's disease in this case, suggesting that HPV-related Bowen's disease is not always restricted to genital or finger lesions.     

A novel mutation, 1234del(C), of the IRF6 in a Thai family with Van der Woude syndrome

Van der Woude syndrome (VWS) is an autosomal dominant disorder and the most common cleft syndrome characterized by cleft lip and palate with lip pits. Very recently, mutations in the interferon regulatory factor 6 gene (IRF6) were identified to cause VWS in patients of northern European descent. We describe a Thai family with VWS. The proband, an 8-month-old boy, had bilateral complete cleft lip and palate, and two conical elevations with lip pits on his lower lip. Four other family members had various manifestations of the clefts and lower lip pits. Mutation analysis of the proband and his mother for the entire coding region of IRF6 identified a novel mutation, 1234del(C), in its exon 9. The deletion is expected to result in some amino acid changes followed by truncation at amino acid 435. This observation supports that IRF6 is the gene responsible for VWS across different populations and that haploinsufficiency of the gene disturbs development of the lip and palate.     

Prognostic significance of macroscopic serosal invasion in advanced gastric cancer

BACKGROUND/AIMS: Although histologic invasion of the gastric serosa is associated with poor prognosis in patients with gastric cancer, the prognostic significance of macroscopic invasion of the serosa is not clear. The aim of this study was to clarify the clinical significance of macroscopic serosal invasion in advanced gastric cancer. METHODOLOGY: Clinicopathologic data from 257 patients who underwent curative gastrectomy for advanced gastric cancer was analyzed to evaluate the prognostic significance of macroscopic serosal invasion. On the basis of macroscopic findings, tumors were classified as SO, negative serosal invasion; S1, positive serosal invasion; or S2, invasion extending to the adjacent organ. We also examined the relation between the extent of macroscopic serosal invasion (SO, S1, S2) and volumetric shape of cancerous invasion (funnel, column, and mountain types). RESULTS: In comparison with SO tumors, S1 and S2 tumors were significantly more likely to be more than 5cm in diameter and show histologically serosal invasion. Volumetric analysis showed that S1 and S2 tumors were more frequently column- or mountain-shaped than were SO tumors. The 5-year survival rate differed significantly between patients with SO, S1, and S2 tumors (88% us. 65% vs. 18%, P<0.01). Multivariate analysis indicated that macroscopic serosal invasion was an independent prognostic factor. CONCLUSIONS: Macroscopic serosal invasion is associated with extensive cancerous invasion of the deep gastric wall. The presence of macroscopic serosal invasion indicates advanced tumor progression and poor prognosis for patients with advanced gastric cancer. Clinically, knowledge of the extent of macroscopic serosal invasion is helpful in planning adjuvant chemotherapy.     

GABAB receptor transduction mechanisms, and cross-talk between protein kinases A and C, in GABAergic terminals synapsing onto neurons of the rat nucleus basalis of Meynert

The transduction mechanisms underlying presynaptic GABA_B receptor-mediated inhibition of transmitter release have been characterized for a variety of synapses in the central nervous system (CNS). These studies have suggested a range of transduction mechanisms, including a role for second messengers such as protein kinases A (PKA) and C (PKC). In the present study, we have examined the intracellular signalling pathways underlying baclofen-induced inhibition of GABA release from terminals synapsing onto rat basalis of Meynert neurons using patch-clamp recordings. Baclofen, a selective GABA_B receptor agonist, reversibly decreased both evoked and spontaneous, miniature, GABAergic inhibitory postsynaptic currents (eIPSCs and mIPSCs, respectively). Such baclofen actions were completely abolished by CGP55845A, a selective GABA_B receptor antagonist, and by staurosporine, a non-selective PKA and PKC inhibitor. The mIPSC frequency was still decreased by baclofen even in the presence of 4 AP, a K⁺ channel blocker, and Cd²⁺, a voltage-dependent calcium channel blocker. Pharmacological activation or inhibition of PKC activity affected basal GABA release and mildly affected the response to baclofen. Inhibition of the cAMP/PKA cascade also affected basal GABA release and, in a subset of neurons, occluded the effects of baclofen, suggesting that the GABA_B receptor-mediated inhibitory action on GABA release was mediated via decreases in PKA activity. In addition, PKA inhibition occluded the effects of PKC modulation on both basal GABA release and on the response to baclofen. Our results characterize the transduction pathway of baclofen at these nucleus basalis of Maynert (nBM) synapses and show, for the first time, some cross-talk between the cAMP/PKA and PKC pathways in mammalian presynaptic nerve terminals.     

Novel observation of hot-cold-hot hemolysis exhibited by group B streptococci

Six human isolates of group B streptococci (GBS) were cultured on blood agar anaerobically at 37 degrees C for 18 h and then at 4 degrees C for 6 h and reincubated anaerobically at 37 degrees C for 6 h. Three of the strains showed a marked enlargement of the hemolysis zone compared with that obtained after hot-only (37 degrees C for 18 h) or hot-cold (37 degrees C for 18 h and then 4 degrees C for 6 h) treatment. Subsequent broth culture experiments revealed that enhanced hemolytic activity due to hot-cold-hot treatment was observed in all 6 GBS strains when cultured in the presence of starch.     

Adenosine A1 receptor-mediated presynaptic inhibition of GABAergic transmission in immature rat hippocampal CA1 neurons

In the mechanically dissociated rat hippocampal CA1 neurons with native presynaptic nerve endings, namely "synaptic bouton" preparation, the purinergic modulation of spontaneous GABAergic miniature inhibitory postsynaptic currents (mIPSCs) was investigated using whole-cell recording mode under the voltage-clamp conditions. In immature neurons, adenosine (10 microM) reversibly decreased GABAergic mIPSC frequency without affecting the mean current amplitude. The inhibitory effect of adenosine transmission was completely blocked by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 nM), a selective Alpha(1) receptor antagonist, and was mimicked by N(6)-cyclopentyladenosine (CPA, 1 microM), a selective Alpha(1) receptor agonist. However, CPA had no effect on GABAergic mIPSC frequency in postnatal 30 day neurons. N-ethylmaleimide (10 microM), a guanosine 5'-triphosphate binding protein uncoupler, and Ca(2+)-free external solution removed the CPA-induced inhibition of mIPSC frequency. K(+) channel blockers, 4-aminopyridine (100 microM) and Ba(2+) (1 mM), had no effect on the inhibitory effect of CPA on GABAergic mIPSC frequency. Stimulation of adenylyl cyclase with forskolin (10 microM) prevented the CPA action on GABAergic mIPSC frequency. Rp-cAMPS (100 microM), a selective PKA inhibitor, also blocked the CPA action. It was concluded that the activation of presynaptic Alpha(1) receptors modulates the probability of spontaneous GABA release via cAMP- and protein kinase A dependent pathway. This Alpha(1) receptor-mediated modulation of GABAergic transmission may play an important role in the regulation of excitability of immature hippocampal CA1 neurons.     

Administration of interferon for two or more years decreases early stage hepatocellular carcinoma recurrence rate after radical ablation: A retrospective study of hepatitis C virus‐related liver cancer

Background: Since hepatocellular carcinoma often recurs after surgical resection or radiofrequency ablation, we analyzed a retrospective large cohort of patients with small hepatocellular carcinoma caused by hepatitis C virus (HCV). Methods: Among 379 patients with HCV RNA‐positive small hepatocellular carcinoma (multiple up to three nodules, 3 cm or less each), 77 received interferon‐alpha injection and 302 received no anti‐viral therapy. Results: Four patients (5.2%) attained sustained virological response (SVR). Cumulative recurrence rates in the treated and untreated groups were 41.1% and 57.5% at the end of the third year, and 63.0% and 74.5% at the fifth year, respectively (P = 0.013). Fifth year‐recurrence rates in treated group were 25.0% in SVR, 85.7% in biochemical response, 71.1% in no response, and 46.7% in patients with continuous administration. When four patients with SVR were excluded, recurrence rates in short‐term interferon therapy (<2 years) and long‐term therapy (≥2 years) were 46.2% and 39.3% at the third year, and 66.2% and 57.4% at the fifth year, respectively (P = 0.012). Multivariate analysis showed that long‐term interferon therapy significantly decreased recurrence rate (hazard ratio for interferon <2 years 0.80, interferon ≥2 years 0.60, P = 0.044), after adjustment with background covariates including indocyanine green retention rate (P = 0.018), alpha‐fetoprotein (P = 0.051), and tumor treatment (P = 0.066). Conclusion: A long‐term administration of low‐dose interferon significantly decreased recurrence of hepatocellular carcinoma after surgical resection or radiofrequency ablation.     

Histological evidence of the altered distribution of osteocytes and bone matrix synthesis in klotho-deficient mice

Mice homozygous for klotho gene deletion are well established aging models as they mimic certain aspects of human senescence e.g. osteoporosis. Induced senescence may affect cellular functions and alter the histological properties of the extracellular matrices. The present study examined the histological and ultrastructural features of osteocytes and the surrounding bone matrix in klotho-deficient mice. As expected, osteoblasts showed a flattened shape with a weak immunoreactivity for alkaline phosphatase, and the bone matrix contained many empty osteocytic lacunae. The walls of both normal and empty lacunae were intensely immunopositive for osteopontin and dentin matrix protein-1, but featured an inconsistent immunoreactivity for osteocalcin and type I collagen. Not surprisingly, TUNEL-positivity, indicative of apoptosis, was found in many osteoblasts, osteocytes, and bone marrow cells of the klotho-deficient mice. In transmission electron microscopy, an amorphous matrix containing non-collagenous organic materials was recognizable around osteoblasts and in the osteocytic lacunae. Some osteoblasts on the bone surface featured these amorphous materials in vacuoles associated with their trans-Golgi network, indicating that, under klotho-deficient conditions, they synthesize and secrete the non-collagenous structures. Some osteocytes displayed pyknosis or degenerative traits. Thus, our findings provide histological evidence that klotho gene deletion influences the spatial distribution of osteocytes and the synthesis of bone matrix proteins in addition to the accelerated aging of bone cells.