The effects of cortisol and adrenal androgen on bone mass in Asians with and without subclinical hypercortisolism.

Analyses using the largest Korean cohort of adrenal incidentaloma (AI) revealed that subtle cortisol excess in premenopausal women and reduced dehydroepiandrosterone-sulfate (DHEA-S) in postmenopausal women and men are associated with bone mineral density (BMD) reduction in Asian patients with subclinical hypercortisolism (SH). INTRODUCTION: Few studies evaluated bone metabolism in Asians with SH. We investigated associations of cortisol and DHEA-S, an adrenal androgen, with BMD in Asians with AI, with or without SH. METHODS: We used cross-sectional data of a prospective multicenter study from Korea. We measured BMD, bone turnover markers, cortisol levels after 1-mg dexamethasone suppression test (1-mg DST), DHEA-S, and baseline cortisol to DHEA-S ratio (cort/DHEA-S) in 109 AI patients with SH (18 premenopausal, 38 postmenopausal women, and 53 men) and 686 with non-functional AI (NFAI; 59 premenopausal, 199 postmenopausal women, and 428 men). RESULTS: Pre- and postmenopausal women, but not men, with SH had lower BMDs at lumbar spine (LS) than those with NFAI (P = 0.008~0.016). Premenopausal women with SH also had lower BMDs at the hip than those with NFAI (P = 0.009~0.012). After adjusting for confounders, cortisol levels after 1-mg DST demonstrated inverse associations with BMDs at all skeletal sites only in premenopausal women (ß = - 0.042~- 0.033, P = 0.019~0.040). DHEA-S had positive associations with LS BMD in postmenopausal women (ß = 0.096, P = 0.001) and men (ß = 0.029, P = 0.038). The cort/DHEA-S had inverse associations with LS BMD in postmenopausal women (ß = - 0.081, P = 0.004) and men (ß = - 0.029, P = 0.011). These inverse associations of cort/DHEA-S remained significant after adjusting for cortisol levels after 1-mg DST (ß = - 0.079~- 0.026, P = 0.006~0.029). In postmenopausal women, the odds ratios of lower BMD by DHEA-S and cort/DHEA-S was 0.26 (95% CI, 0.08-0.82) and 3.40 (95% CI, 1.12-10.33), respectively. CONCLUSION: Subtle cortisol excess in premenopausal women and reduced DHEA-S in postmenopausal women and men may contribute to BMD reduction in Asians with SH.

Are patients with mild to moderate renal impairment on metformin or other oral anti-hyperglycaemic agents at increased risk of contrast-induced nephropathy and metabolic acidosis after radiocontrast exposure?

AIM: To investigate whether the use of metformin during computed tomography (CT) with radiocontrast agents increases the risk of contrast-induced nephropathy (CIN) and metabolic acidosis after CT in type 2 diabetes patients with mild to moderate renal failure. MATERIALS AND METHODS: Patient records from January 2015 to December 2017 were reviewed retrospectively. A total of 374 patients were included in the final analysis. Of them, 157 patients received metformin, and 217 patients were taking other oral hypoglycaemic agents (OHAs) during radiocontrast administration. RESULTS: No significant difference in CIN incidence was observed between the metformin use group and the other OHAs group (p=0.085). Metabolic acidosis after CT was seen in 91 (58%) patients who used metformin and 141 (65%) patients who were taking other OHAs. There was no relationship between metabolic acidosis after CT and the use of metformin (p=0.195). Metabolic acidosis after radiocontrast agent exposure was associated with malignant disease, low serum albumin level, and low serum total CO2 level at baseline. CONCLUSION: These data show that other factors, but not metformin use, are associated with metabolic acidosis after radiocontrast agent exposure in patients with reduced renal function. These data support current recommendations that there is no need to discontinue metformin before CT using radiocontrast agents in patients with mild to moderate renal failure.

A direct role for hepatitis B virus X protein in inducing mitochondrial membrane permeabilization.

Hepatitis B virus X protein (HBx) acts as a multifunctional protein that regulates intracellular signalling pathways during HBV infection. It has mainly been studied in terms of its interaction with cellular proteins. Here, we show that HBx induces membrane permeabilization independently of the mitochondrial permeability transition pore complex. We generated mitochondrial outer membrane-mimic liposomes to observe the direct effects of HBx on membranes. We found that HBx induced membrane permeabilization, and the region comprising the transmembrane domain and the mitochondrial-targeting sequence was sufficient for this process. Membrane permeabilization was inhibited by nonselective channel blockers or by N-(n-nonyl)deoxynojirimycin (NN-DNJ), a viroporin inhibitor. Moreover, NN-DNJ inhibited HBx-induced mitochondrial depolarization in Huh-7 cells. Based on the results of this study, we can postulate that the HBx protein itself is sufficient to induce mitochondrial membrane permeabilization. Our finding provides important information for a strategy of HBx targeting during HBV treatment.

Delayed viral suppression during antiviral therapy is associated with increased hepatocellular carcinoma rates in HBeAg-positive high viral load chronic hepatitis B.

The treatment option in chronic hepatitis B (CHB) patients with persistent low-level viremia despite entecavir or tenofovir monotherapy is unclear. This study investigated the development of hepatocellular carcinoma (HCC) or cirrhosis in hepatitis B e antigen (HBeAg)-positive high viral load CHB patients, according to the time needed to achieve complete viral suppression. A total of 325 HBeAg-positive CHB patients with high viral load who were recently started on antiviral therapy with entecavir or tenofovir were included. The enrolled patients were divided into 2 groups with 4 separate criteria based on the time needed to achieve complete viral suppression: within 1, 2, 3 or 4 years of therapy initiation. The outcomes were development of HCC and cirrhosis. The cumulative incidence of HCC was significantly higher in patients failing complete viral suppression within 1 year (hazard ratio (HR), 4.54; 95% confidence interval (CI), 1.03-19.93; P = .045) or 2 years (HR, 3.38; 95% CI, 1.24-9.23; P = .018), than patients who achieved complete viral suppression within 1 or 2 years, respectively. Cumulative incidence of cirrhosis was also significantly higher in patients failing suppression within 1 year (HR, 1.95; 95% CI, 1.04-3.66; P = .037) or 2 years (HR, 2.44; 95% CI, 1.41-4.22; P = .001). When the time for achieving viral suppression exceeded 2 years, the cumulative incidence of HCC or cirrhosis was not different regardless of viral suppression. Complete hepatitis B virus suppression within 2 years of antiviral therapy initiation is associated with risk reduction in HCC or cirrhosis development.

Comparison of overall survival between antiviral-induced viral suppression and inactive phase chronic hepatitis B patients.

Nucleot(s)ide analogues (NAs) reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. However, the risk of HCC is reportedly higher for NA-treated patients than for patients in the inactive CHB phase. This study aimed to compare the long-term outcomes of CHB patients with NA-induced viral suppression and those of patients with inactive CHB. This retrospective study involved 1118 consecutive CHB patients whose HBV DNA level was continuously <2000 IU/mL during follow-up with/without antiviral agents. The patients were classified into inactive CHB (n = 373) or NA groups (n = 745). The primary endpoint was overall survival. Secondary endpoints included development of HCC and other liver-related events. The median duration of follow-up was 41.0 (interquartile range = 26.5-55.0) months. The difference in overall survival between the NA group vs. the inactive CHB group was not significant (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.33-1.85; P = .57). The NA group showed a significantly higher risk of HCC (HR = 3.44; 95% CI = 1.82-6.52; P < .01), but comparable risk for non-HCC liver-related events (HR = 1.02; 95% CI = 0.66-1.59; P = .93), compared with the inactive CHB group. Among patients with cirrhosis, the NA group showed a significantly lower risk of death (HR = 0.31; 95% CI = 0.097-0.998; P = .05) and non-HCC liver-related events (HR = 0.51; 95% CI = 0.31-0.83; P < .01), but a slightly higher risk of HCC (HR = 2.39; 95% CI = 0.85-6.75; P = .09), compared to the inactive CHB group. The overall survival of untreated patients with inactive CHB and of CHB patients achieving viral suppression with NA was comparable. However, NA treatment of cirrhotic patients was significantly associated with longer overall survival and lower risk of liver-related events.

Entecavir and tenofovir reduce hepatitis B virus-related hepatocellular carcinoma recurrence more effectively than other antivirals.

Nucleos(t)ide analogues (NAs) have been shown to decrease the risk of hepatocellular carcinoma (HCC) recurrence. This study evaluated whether high-potency NAs (entecavir and tenofovir disoproxil fumarate [TDF]) reduce the risk of tumour recurrence more potently than low-potency NAs after curative treatment of hepatitis B virus (HBV)-related HCC. This study included 607 consecutive HBV-related HCC patients treated with surgical resection or radiofrequency ablation. The patients were categorized into three groups according to antiviral treatment: group A (no antiviral; n = 261), group B (low-potency NA; n = 90) and group C (high-potency NA; n = 256). The primary end-point was recurrence-free survival (RFS). During the duration of follow-up, the median RFS was 29.4, 25.1, and 88.2 months in groups A, B and C, respectively (P < .001, log-rank test). The multivariate Cox analysis indicated that group C had a significantly longer RFS than both group A (adjusted hazard ratio [HR] = 0.39, P < .001) and group B (adjusted HR = 0.47, P < .001). When baseline characteristics were balanced using inverse probability weighting, group C still had a significantly longer RFS than group A (adjusted HR = 0.46, P < .001) and group B (adjusted HR = 0.59, P = .007). Group C had significantly lower risk of viral breakthrough than group B (HR = 0.19, P < .001). Viral breakthrough was an independent risk factor for shorter RFS among groups B and C (adjusted HR = 2.03, P = .007, time-dependent Cox analysis). Antiviral agents with high genetic barrier to resistance (entecavir and TDF) reduced the risk of HCC recurrence compared with other antivirals and no antiviral treatment, especially in patients with high baseline viral load.

Serum 25-hydroxyvitamin D cutoffs for functional bone measures in postmenopausal osteoporosis.

This study sought to determine the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health in postmenopausal women with low bone mass. A serum 25(OH)D concentration of 20 ng/mL rather than 30 ng/mL was appropriate for bone health. INTRODUCTION: There is no consensus on the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health. The aim of this study was to investigate the relationship between 25(OH)D measured via liquid chromatography-mass spectrometry (LC-MS/MS), which is the current gold standard, and biochemical markers of bone turnover, PTH, and bone mineral densitometry (BMD). METHODS: The medical records of 750 postmenopausal women newly diagnosed with osteoporosis or osteopenia at Samsung Medical Center from 2009 to 2014 were investigated. Subjects were divided into four groups according to serum 25(OH)D concentration: <10, 10-20, 20-30, and ≥30 ng/mL. Serum concentrations of bone-specific alkaline phosphatase (BS-ALP), carboxy-terminal cross-linking telopeptide of type 1 collagen (CTx), intact PTH (iPTH), and BMD were compared among the four groups using analysis of covariance. Thresholds of 25(OH)D were then assessed using spline plots and locally weighted regression smoothing (LOESS) plots. RESULTS: 25(OH)D was negatively correlated with serum BS-ALP, CTx, and iPTH. Only femur neck and total femur BMD had significant positive relationships with 25(OH)D. Cutoff values of 11.9 and 9.7 ng/mL were estimated from the spline plots of femur neck and total femur BMD, respectively. For iPTH, the LOESS plot showed a steep decrease to a serum 25(OH)D concentration of about 20 ng/mL, followed by a plateau. CONCLUSIONS: According to this study, a serum 25(OH)D concentration of 20 ng/mL, rather than 30 ng/mL, was appropriate for bone health.

Association between the extent of urinary albumin excretion and glycaemic variability indices measured by continuous glucose monitoring.

AIMS: The contribution of glycaemic variability to the microvascular complication of diabetes has not been established. We examined whether there is an independent association between indices of glycaemic variability in continuous glucose monitoring and extent of albuminuria. METHODS: A total of 173 patients with Type 2 diabetes (without insulin therapy, n = 96; with insulin therapy, n = 77) who had unexplained large fluctuations in blood glucose values underwent three-day continuous glucose monitoring. We used a multinomial logistic regression model to determine whether the indices of glycaemic variability independently affected the odds of having a spot urine albumin/creatinine ratio of 30-299 mg/g and ≥ 300 mg/g. RESULTS: Higher standard deviation (P = 0.002), mean of daily differences (P = 0.023) and mean amplitude of glycaemic excursion (P = 0.043) significantly increased the odds of having a urine albumin/creatinine ratio of ≥ 300 mg/g. In multivariable analysis, only higher standard deviation, but not mean amplitude of glycaemic excursion and mean of daily differences, independently increased the odds of having a urine albumin/creatinine ratio of ≥ 300 mg/g (P = 0.025). Coefficient of variation (sd/mean) was not associated with the odds of having a urine albumin/creatinine ratio of 30-299 or ≥ 300 mg/g. CONCLUSIONS: The independent association between standard deviation and the extent of albuminuria was lost when the measures were normalized by mean glucose level. At least in terms of relative measures of glycaemic variability, we failed to demonstrate an independent association between glycaemic variability and albuminuria extent in patients with inadequately controlled Type 2 diabetes.

Relationship between polymorphisms near the IL28B gene and spontaneous HBsAg seroclearance: a systematic review and meta-analysis.

Polymorphisms near the interleukin (IL) 28B gene have been proposed to be associated with spontaneous clearance of the hepatitis C virus. The purpose of this study was to assess the relationship between IL28B polymorphisms and the rate of spontaneous hepatitis B surface antigen (HBsAg) seroclearance by means of meta-analysis. MEDLINE/PubMed and EMBASE were utilized to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were analysed together to assess the strength of the association. Subgroup analyses were mainly performed according to ethnicity. A total of 4028 cases with persistent chronic hepatitis B and 2327 spontaneously recovered controls were included from 11 studies. The single nucleotide polymorphism (SNP), rs12979860, had no significant association with HBsAg seroclearance (OR = 0.98, 95% CI: 0.84-1.14 in the dominant model; OR = 1.00, 95% CI: 0.68-1.46 in the recessive model; and OR = 0.95, 95% CI: 0.82-1.09 in the allelic model). The SNP, rs12980275, had no significant association either (OR = 1.03, 95% CI: 0.84-1.26 in the dominant model; OR = 1.17, 95% CI: 0.46-2.96 in the recessive model; and OR = 1.04, 95% CI: 0.86-1.26 in the allelic model), nor did the SNP, rs8099917 (OR = 0.94, 95% CI: 0.77-1.15 in the dominant model; OR = 0.74, 95% CI: 0.34-1.62 in the recessive model; and OR = 0.93, 95% CI: 0.77-1.13 in the allelic model). Similarly, the results of subgroup analyses by ethnicity also showed no association in either the Asian group or non-Asian group. We concluded that there was no significant association between common IL28B polymorphisms and the rate of spontaneous HBsAg seroclearance.

Intensity of surveillance for hepatocellular carcinoma determines survival in patients at risk in a hepatitis B-endemic area.

BACKGROUND: Data are insufficient regarding the survival benefit of surveillance for hepatocellular carcinoma (HCC). AIM: To investigate the effectiveness of HCC surveillance in a hepatitis B-endemic population. METHODS: This retrospective cohort study included 1402 consecutive patients who were newly diagnosed with HCC between 2005 and 2012 at a single tertiary hospital in Korea. The primary endpoint was overall survival. Lead-time and length-time biases were adjusted (sojourn time = 140 days) and sensitivity analyses were performed. RESULTS: The most common aetiology was hepatitis B (80.4%). Cirrhosis was present in 78.2%. HCC was diagnosed during regular surveillance (defined as mean interval of ultrasonography <8 months, n = 834), irregular surveillance (n = 104) or nonsurveillance (n = 464). Patients in the regular surveillance group were diagnosed at earlier stages ([very] early stage, 64.4%) than the irregular surveillance (40.4%) or nonsurveillance (26.9%) groups and had more chance for curative treatments (52.4%) than the irregular surveillance (39.4%) or nonsurveillance (23.3%) groups (all P < 0.001). Mortality risk was significantly lower in the regular surveillance group (adjusted hazard ratio [aHR], 0.69; 95% [CI], 0.57-0.83) but not in the irregular surveillance group (aHR, 0.94; 95% CI, 0.69-1.28) compared with the nonsurveillance group after adjusting for confounding factors and lead-time. When the subjects were restricted to cirrhotic patients or Child-Pugh class A/B patients, similar results were obtained for mortality risk reduction between groups. CONCLUSIONS: HCC surveillance was associated with longer survival owing to earlier diagnosis and curative treatment. Survival advantage was significant with regular surveillance but not with irregular surveillance.

New myeloablative conditioning regimen with fludarabine and busulfan for allogeneic stem cell transplantation: comparison with BuCy2.

A regimen of busulfan and cyclophosphamide (BuCy2) is regarded as the standard myeloablative regimen for SCT. This study evaluated the hypothesis that fludarabine can replace cyclophosphamide for myeloablative allogeneic SCT. Ninety-five patients underwent allogeneic SCT from HLA-identical donors, following BuCy2 (n=55) or busulfan+fludarabine (BF, n=40). The efficacy of fludarabine compared to cyclophosphamide was retrospectively evaluated. The BF group exhibited a shorter duration until engraftment (P=0.001), lower incidence of acute and chronic GVHD (P<0.001 and P=0.003, respectively), and non-relapse mortality (NRM) (P=0.039). Furthermore, the event-free survival and overall survival were significantly higher for the BF group compared to the BuCy2 group (P=0.004 and 0.002, respectively). After adjusting for age, the risk status of disease, GVHD prophylaxis and donor type, the BF regimen was found to be an independent favorable risk factor for event-free survival (hazard ratio (HR), 0.181; 95% confidence interval, 0.045-0.720; P=0.016) and overall survival (HR, 0.168; 0.035-0.807; P=0.026). The replacement of cyclophosphamide with fludarabine for myeloablative conditioning seems to be more effective in terms of short-term NRM, and GVHD compared to BuCy2 regimen in allogeneic transplantation.

Rifaximin treatment is associated with reduced risk of cirrhotic complications and prolonged overall survival in patients experiencing hepatic encephalopathy.

BACKGROUND: Rifaximin might decrease the risk of portal hypertension-related complications by controlling small intestinal bacterial overgrowth. AIM: To evaluate whether rifaximin was associated with the risk of death and cirrhotic complications. METHODS: We conducted a retrospective study that included 1042 patients experiencing hepatic encephalopathy (HE): 421 patients without hepatocellular carcinoma (HCC; the non-HCC cohort) and 621 patients with HCC (the HCC cohort). The primary endpoint was overall survival and secondary endpoints were recurrence of HE and the development of spontaneous bacterial peritonitis (SBP), hepatorenal syndrome (HRS) and variceal bleeding. RESULTS: In the non-HCC cohort, 145 patients received rifaximin plus lactulose (the rifaximin group) and 276 patients received lactulose alone (the control group). The multivariate analysis revealed that rifaximin was significantly associated with lower risk of death (adjusted hazard ratio [aHR], 0.697; P = .024) and reduced the risk of recurrent HE (aHR, 0.452; P < .001), SBP (aHR, 0.210; P < .001) and variceal bleeding (aHR, 0.425; P = .011) but not HRS (aHR, 0.598; P = .08). In the HCC cohort, 173 patients received rifaximin plus lactulose and 448 patients received lactulose. Rifaximin was not associated with the risk of death (aHR, 1.177; P = .121). Rifaximin was associated with lower risk of SBP (aHR, 0.323; P < .001) but not with variceal bleeding (aHR, 0.660; P = .104) or recurrent HE (aHR, 0.689; P = .057). The risk of Clostridium difficile-associated diarrhoea was not different between the groups (aHR, 0.028; P = .338). CONCLUSIONS: In patients without HCC, rifaximin treatment was significantly associated with prolonged overall survival and reduced risks of spontaneous bacterial peritonitis, variceal bleeding and recurrent hepatic encephalopathy.

Fyn is a redox sensor involved in solar ultraviolet light-induced signal transduction in skin carcinogenesis.

Solar ultraviolet (UV) light is a major etiological factor in skin carcinogenesis, with solar UV-stimulated signal transduction inducing pathological changes and skin damage. The primary sensor of solar UV-induced cellular signaling has not been identified. We use an experimental system of solar simulated light (SSL) to mimic solar UV and we demonstrate that Fyn is a primary redox sensor involved in SSL-induced signal transduction. Reactive oxygen species (ROS) generated by SSL exposure directly oxidize Cys488 of Fyn, resulting in increased Fyn kinase activity. Fyn oxidation was increased in mouse skin after SSL exposure and Fyn-knockout mice formed larger and more tumors compared with Fyn wild-type mice when exposed to SSL for an extended period of time. Murine embryonic fibroblasts (MEFs) lacking Fyn and cells in which Fyn expression was knocked down were resistant to SSL-induced apoptosis. Furthermore, cells expressing mutant Fyn (C448A) were resistant to SSL-induced apoptosis. These findings suggest that Fyn acts as a regulatory nexus between solar UV, ROS and signal transduction during skin carcinogenesis.

Fatty acid induced glioma cell growth is mediated by the acyl-CoA synthetase 5 gene located on chromosome 10q25.1-q25.2, a region frequently deleted in malignant gliomas.

Acyl-CoA synthetase (ACS) ligates fatty acid and CoA to produce acyl-CoA, an essential molecule in fatty acid metabolism and cell proliferation. ACS5 is a recently characterized ACS isozyme highly expressed in proliferating 3T3-L1 cells. Molecular characterization of the human ACS5 gene revealed that the gene is located on chromosome 10q25.1-q25.2, spans approximately 46 kb, comprises 21 exons and 22 introns, and encodes a 683 amino acid protein. Two major ACS5 transcripts of 2.5- and 3.7-kb are distributed in a wide range of tissues with the highest expression in uterus and spleen. Markedly increased levels of ACS5 transcripts were detected in a glioma line, A172 cells, and primary gliomas of grade IV malignancy, while ACS5 expression was found to be low in normal brain. Immunohistochemical analysis also revealed strong immunostaining with an anti-ACS5 antibody in glioblastomas. U87MG glioma cells infected with an adenovirus encoding ACS5 displayed induced cell growth on exposure to palmitate. Consistent with the induction of cell growth, the virus infected cells displayed induced uptake of palmitate. These results demonstrate a novel fatty acid-induced glioma cell growth mediated by ACS5.

Effect of high dietary sodium on bone turnover markers and urinary calcium excretion in Korean postmenopausal women with low bone mass.

BACKGROUND/OBJECTIVES: High salt intake is a well-recognized risk factor of osteoporosis for its modulating effect on calcium metabolism. To understand the effect of dietary sodium on bone turnover, we evaluated the association between urinary sodium excretion and bone turnover markers in Korean postmenopausal women with low bone mass. SUBJECTS/METHODS: A retrospective review of medical records at a single institution identified 537 postmenopausal women who were first diagnosed with osteopenia or osteoporosis between 2008 and 2013. Subjects were stratified by low (<2 g/day, n=77), moderate (2-4.4 g/day, n=354) and high (⩾4.4 g/day, n=106) sodium excretion. A 24-h urine was collected to estimate sodium, calcium and creatinine. Bone turnover markers and calciotropic hormones were measured in serum. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry. RESULTS: Sodium intake was positively associated with urinary sodium excretion (P=0.006, r=0.29). Bone turnover markers were significantly higher in the moderate-to-high urinary sodium excretion group (⩾2 g/day) than in the low urinary sodium excretion group (<2 g/day); CTX-I (C-telopeptides of type I collagen) was 21.3% higher (P=0.001) and osteocalcin (OC) was 15.7% higher (P=0.004). Calciotropic hormones and BMD were not significantly different across the sodium excretion groups. CONCLUSIONS: High urinary sodium excretion (⩾2 g/day) increased bone turnover markers in Korean postmenopausal women, suggesting that excessive sodium intake might accelerate bone turnover.

Mammary gland tumor in transgenic mice expressing targeted beta-casein/HPV16E6 fusion gene.

The human papillomaviruses (HPV)-16 and HPV-18 referred to as high-risk HPVs are strongly associated with anogenital malignancies as well as benign epithelial cysts. It has been demonstrated that transgenic mice carrying HPV-16 E6-E7 under the control of the MMTV LTR developed malignant tumors including salivary gland carcinoma, lymphoma, skin histiocytomas and testicular tumors in a non-mammary gland specific manner. Another regulatory unit of rat beta-casein gene can confer the expression of fusion gene preferentially in the mammary glands of transgenic mice in a developmentally regulated manner. In order to generate mammary tumor formation in transgenic mice directing HPV16E6 gene alone into the mammary gland, this regulatory unit was fused to the E6 gene of HPV-16 type to constructing fusion gene. By screening 51 newborn founder transgenic mice, three mice carrying transgenes were identified. One line termed TG32 developed in a mammary gland tumor with large subcutaneous mass in the left rib region at 17 months of age. The levels of E6 transcript in the mass-tumor of TG32 line were lower than those in non-tumor mammary gland of identical TG32 and of TG250. In each tissue of TG32 line, high expression of E6 transcript was detected both in the mammary gland and brain. Histological analysis showed that cells from mammary gland tumor of the TG32 line had also hyperplasia appearance, with irregular or increased total number of mitotic rate. These observations suggest that developing phenotype and the level of E6 transcripts in the process of malignant transformation may have different mechanisms involving the capacity to bind and destabilize p53, although for confirmation it is necessary to investigate many more transgenic mice.

Ethanol decreases the expression of mitochondrial cytochrome c oxidase mRNA in the rat.

To evaluate the molecular and cellular bases of effects of ethanol on the brain, we utilized a differential display-polymerase chain reaction. Several cDNA fragments were differentially expressed in the hippocampus of control vs. ethanol-treated rats. One of these genes was homologous to the rat mitochondrial cytochrome c oxidase mRNA. Northern blot analysis revealed that the expression of this message in the whole hippocampus was clearly lower after ethanol treatment. Using in situ hybridization, we also found that cytochrome c oxidase mRNA expression, especially in the CA1 and CA3 of the hippocampal regions, was significantly decreased by ethanol treatment. As cytochrome c oxidase is related to oxidative stress, the present study suggests that ethanol might affect the brain through modulation of an oxidative stress reaction.

Lymphoproliferative response to synthetic V3 loop P18 peptide and HIV-1 envelope glycoprotein among individuals immunized with gp160 candidate vaccines.

Because T-cell responses are critical for defense against viral infections, the synthetic P18 peptide (RIQRGPGRAFVTIGK) and active component of gp160 protein has previously been shown to induce cytotoxic and helper T-lymphocyte responses. In order to further define the T-helper cells, responses which are known to play a role in enhancing the immunological response to foreign antigen, we studied the response of individuals immunized with HIV gp160 candidate vaccines. We investigated the proliferative cellular response of peripheral blood mononuclear cells (PBMC) derived from individuals immunized with gp160 antigens in three different protocols. We found a PBMC proliferative response to synthetic P18 peptide in healthy immunized individuals induced by gp160 antigen with or without vaccinia virus. There was correlation between the proliferative response to P18 peptide and other antigens such as HIV-like proteins and gp160 molecule. HLA-DR typing revealed the possible presentation of P18 peptide by several different class II molecules. Since these class II molecules occur frequently in the general population, P18 peptide appears to contain broadly reactive epitopes and thus is presented by multiple HLA class II molecules. Due to its broad reactivity P18 peptide is one of the candidates for inclusion as a subunit vaccine against HIV-1.

Contribution of cohort studies in understanding HIV pathogenesis: introduction of the GRIV cohort and preliminary results.

In the present paper we review studies performed on HIV-infected patients cohorts in order to understand AIDS disease development. The interplay between diverse factors such as the HIV envelope proteins, cellular co-receptors, the immune response with chemokines and cytokines production define the viral tropism, cytopathicity and progression of HIV disease. We present the trends of the research particularly in the domain concerning host genetics. In this context, we describe the GRIV cohort of fast and slow/non-progressors, and its use for understanding basic features of the yet unknown HIV pathogenesis mechanisms.

Effect of purified IgGs from HIV-1-infected and non infected individuals on immune activation.

The purification and analysis of IgGs from sera of HIV-1-infected and non infected individuals are reported. The effect of antibodies purified from sera of infected individuals on antigen-induced T cell proliferation was investigated in relation to their possible involvement in an autoimmune reaction in AIDS, in view of the previously unravelled striking peptide similarities between HIV-1 gp120 and the immunoregulatory CD4 and Fas molecules. However, our data do not allow definite conclusions to be drawn. The necessity of purifying antibodies against specific peptides to show their direct effect on T-cell activation is further stressed.