Stimulation of the center of the lateral reticular nucleus suppresses the swallowing reflex in rats

Morphological studies have demonstrated that the lateral reticular nucleus (LRt) receives fibers projected from sites that are related to control of the swallowing reflex. Although the LRt may therefore be related to control of the swallowing reflex, the functional role of the LRt in the swallowing reflex remains unknown. The present study examined whether the swallowing reflex is modulated by stimulation of the LRt. These experiments were performed on rats anesthetized by urethane. The swallowing reflex was evoked by repetitive electrical stimulation of the superior laryngeal nerve (SLN) and was identified by electromyographic activities from the mylohyoid muscle. Electrical stimulation was applied to the LRt or glutamate was injected into the LRt. The number of swallows was reduced, and the latency of the onset of the first swallow was increased during electrical stimulation near the middle of the rostrocaudal direction of the LRt. The number of swallows was reduced, and the latency of onset of the first swallow increased after microinjection of glutamate near the rostrocaudal center of the LRt. The present study suggests that the LRt is involved in control of the swallowing reflex.

[A case of successful treatment of hepatocellular carcinoma lumbar metastasis by surgery, chemotherapy, and radiation]

The incidence of bone metastasis in patients with hepatocellular carcinoma (HCC) has reportedly been increasing. We report a progressive case that presented with a solitary HCC lumbar metastasis. A 44-year-old man was referred to us from a local clinic with a complaint of a painful lump. He was diagnosed with HCC due to liver cirrhosis and lumbar metastasis by contrast abdominal computerized tomography and magnetic resonance imaging. Then, he received radiation therapy (3 Gy/ time; total, 39 Gy) and zoledronate. Furthermore, transcatheter arterial embolization and posterior lumbar spinal fusion were performed to treat the lumbar metastasis. This decreased his pain and oxycodone was no longer required. In conclusion, for HCC patients with bone metastasis, combined treatment with radiation, zoledronate, and surgery, may possibly improve their quality of life resulting in a long clinical course.

[Interferon therapy to chronic hepatitis type C for the prevention of hepatocarcinogenesis]

Interferon(IFN) therapy for chronic hepatitis(CH) related by hepatitis C virus is useful for the prevention of the appearance of hepatocellular carcinoma(HCC) by both prospective and retrospective study. IFN could be reduced an activity of necro-inflammatory reaction leading toward the reduction of fibrogenesis. Therefore, IFN treated group had a low potential carcinogenesis of the liver indicating the prevention of HCC from CH type C, even if virological complete remmision(CR) could not be obtained after IFN treatment. Biochemical response(BR) group as well as CR group could be inhibited hepatocarcinogenesis compare with non-IFN treated group. Recently, IFN applied for liver cirrhosis as same concept for the prevention of HCC.

Contributions of transgenic mouse studies on the research of hepatitis B virus and hepatitis C virus-induced hepatocarcinogenesis

Transgenic mouse technology has enabled the investigation of the pathogenic effects, including those on development, immunological reactions and carcinogenesis, of viral genes directly in living organism in a real-time manner. Although viral hepatocarcinogenesis comprises multiple sequences of pathological events, that is, chronic necroinflammation and the subsequent regeneration of hepatocytes that induces the accumulation of genetic alterations and hepatocellular carcinoma (HCC), the direct action of viral proteins also play significant roles. The pathogenesis of hepatitis B virus X and hepatitis C virus (HCV) core genes has been extensively studied by virtue of their functions as a transactivator and a steatosis inducer, respectively. In particular, the mechanism of steatosis in HCV infection and its possible association with HCC has been well studied using HCV core gene transgenic mouse models. Although transgenic mouse models have remarkable advantages, they are intrinsically accompanied by some drawbacks when used to study human diseases. Therefore, the results obtained from transgenic mouse studies should be carefully interpreted in the context of whether or not they are well associated with human pathogenesis.

Gamma-ray induced hepatocarcinogenesis in p53-deficient mice

BACKGROUND

Mutations in the p53 gene are frequent genetic alterations in human hepatocellular carcinoma (HCC), but, little is known of the molecular genetic changes that occur during murine hepatocarcinogenesis.

MATERIALS AND METHODS

To characterize the properties of constitutive p53 deficiency that contribute to liver tumor development, a total of 168 F1 mice of two different strains (C3H, which are susceptible to hepatocarcinogenesis and MSM [Mus. M. molossinus] with a single null p53 allele) were exposed to a single 3-Gy dose of whole-body gamma-irradiation at 4 weeks of age and observed for a period of 360 days. The genotype of the mice and the p53 spectrum of the tumors were investigated by polymerase chain reaction (PCR) analysis.

RESULTS

Thirty-five gamma-ray-induced HCCs were obtained as a result of this experiment. 11 (40%) of the mice with liver tumor were wild-type for p53. All liver tumors examined retained the wild-type p53 allele, indicating that p53 itself may not be a target for radiation-induced alteration. Only two p53-deficient mice in the liver tumor group developed thymic lymphomas. The p53-deficient mice showed no significant differences in the number, size, or growth rate of HCC or in the apparent development of HCC.

CONCLUSION

These results indicate that p53 deficiency does not enhance the rate of development or degree of malignancy of radiation-induced HCC in mice but may instead favor the development of multiple primary cancers.

Low-frequency, mild-gradient chronic intermittent hypoxia still induces liver fibrogenesis in mice on a high-fat diet

The fibrogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) may progress when complicated by obstructive sleep apnea (OSA). Studies using animal models have shown that high-frequency intermittent hypoxia (IH) exposure, which resembles human OSA, accelerates liver fibrosis in fatty liver. This study highlights that low-frequency, mild-gradient intermittent hypoxia (IH) can exacerbate fibrogenesis in fatty liver disease, even without significantly raising markers of liver injury or insulin resistance. Using a mice model on a high-fat diet (HFD), we found that while routine liver tests (e.g., ALT, AST) and cholesterol levels remained comparable between HFD mice exposed to room air (RA) versus those exposed to chronic intermittent hypoxia (CIH), indicators of liver fibrosis and oxidative stress were elevated in the latter group. This suggests that even low-frequency, mild-gradient IH can increase oxidative stress and fibrotic activity within the liver, primarily through the upregulation of specific markers like ICAM-1 and osteopontin (OPN), which may play a role CIH-induced liver inflammation and fibrosis in fatty liver. In conclusion. Our study further notes that these hypoxia-related changes occurred without significantly worsening systemic insulin resistance, focusing attention on localized liver impacts rather than global metabolic disruptions. The findings underscore the potential role of oxidative stress and specific cytokines in the progression of liver fibrosis in MASLD, especially when complicated by conditions that introduce IH.

Interferon can block telomere erosion and in rare cases result in hepatocellular carcinoma development with telomeric repeat binding factor 1 overexpression in chronic hepatitis C

PURPOSE

The purpose of this study was to evaluate whether IFN therapy for chronic hepatitis C could overcome telomere reduction in the liver, a possible risk factor for hepatocellular carcinoma (HCC) development.

EXPERIMENTAL DESIGN

Relative telomeric repeat content (RTC) in the liver was measured before and after IFN therapy in 21 chronic hepatitis C cases. Liver samples were obtained at average intervals of 12, 75, and 32 months in eight complete responders (CRs) and one biochemical responder (BR), four CRs in whom HCC developed after an eradication of hepatitis C virus, and eight nonresponders, respectively. Telomeric repeat binding factor 1 (TRF1) was immunostained in specimens from CRs and a BR.

RESULTS

Although the average RTC of 0.96 +/- 0.14 (mean +/- SD) significantly decreased to 0.85 +/- 0.12 after IFN therapy in nonresponders (P = 0.023), the value of 0.91 +/- 0.14 before IFN therapy in CRs and a BR increased significantly to 1.0 +/- 0.085 (P = 0.031). TRF1 expression was barely detectable and attenuated after IFN therapy, except in CRs developing HCC, in which frequent staining appeared, and the RTC evidently decreased from 0.97 +/- 0.11 to 0.63 +/- 0.0092 in corresponding noncancerous liver tissues.

CONCLUSIONS

It is strongly suggested that successful IFN therapy blocks telomere erosion, except in rare cases in which telomere reduction continues with overexpression of TRF1. Successive RTC evaluation in the liver may distinguish a risky case from a clinically cured one.

Absence of pretreatment markers that predict the emergence of YMDD mutants during lamivudine treatment--the results of a prospective multi-center study

BACKGROUND/AIMS

The emergence of YMDD mutants in patients who are treated with lamivudine may determine the clinical prognosis. However, currently there are no clinical or virological factors that predict specifically the emergence of the mutants.

METHODOLOGY

To define these factors, we analyzed 69 patients with chronic hepatitis B infection who were treated with lamivudine (LAM) and followed prospectively for at least 12 months.

RESULTS

Of the 69 patients, 12 (17.4%) developed YMDD mutants up to 12 months after the start of LAM. The incidence of YMDD mutants was slightly higher in those who were younger, had higher HBV DNA titers, lower ALT levels, genotype C, and mutations in the core promoter before treatment. However, we could not find any significant factors that correlated with the appearance of the mutants.

CONCLUSIONS

Currently, using conventional virological assays, it is difficult to predict the development of mutants before LAM treatment. Management of flare-ups of hepatitis, due to the appearance of mutants, should always be envisaged when LAM treatment is started.

Common clinicopathological features of the patients with chronic hepatitis B virus infection who developed hepatocellular carcinoma after seroconversion to anti-HBs--a consideration of the pathogenesis of HBV-induced hepatocellular carcinoma and a strategy to inhibit it

BACKGROUND/AIMS

The incidence of hepatocellular carcinoma among patients who have seroconverted to anti-hepatitis B surface antigen (anti-HBs) remains controversial.

METHODOLOGY

We report four patients with chronic hepatitis B virus (HBV) infection who had cleared HBsAg and had developed anti-HBs at a later time, but who developed hepatocellular carcinoma (HCC) eventually.

RESULTS

The common clinicopathological characteristics of the four patients were: An established diagnosis of precirrhosis or liver cirrhosis more than a decade previously, a long-standing normalization or stabilization at a low level of ALT values due to undetectable HBV DNA by the Amplicore Monitor assay, and a marked reduction of the fibrosis level in the non-tumorous liver obtained at HCC surgery or autopsy compared to the previous histology more than a decade previously. There was no fibrosis in the needle biopsy specimen from one patient.

CONCLUSIONS

Our findings suggest that HCC due to HBV can occur in the serologically-cured stage if progression to pre-cirrhosis or cirrhosis already has occurred, where the fibrosis level has improved considerably because of the long-term absence of active HBV viremia and inflammation. Active medical intervention to prevent liver cirrhosis for chronic hepatitis B may have an important role in the inhibition of HCC in patients with chronic hepatitis B.

Sequence diversity of hepatitis C viral genomes

The nucleotide sequences of cDNAs (275 base-pairs) in the non-structural protein 5 regions of Japanese isolates of hepatitis C virus (HCV-J) from the plasma of 11 patients with non-A, non-B hepatitis and the livers of five patients with hepatocellular carcinoma were analyzed. Approximately 14 to 17% of nucleotide sequences of the HCV-Js examined differed from that of the original isolate in the United States (HCV-US). Furthermore, 2.5 to 11% sequence diversity was found among the HCV-Js. The nucleotide sequences of the HCV-Js showed characteristic common differences from that of HCV-US, although they also showed some random substitutions. Plural HCV-J genomes were found in two of the cDNAs derived from liver specimens, and a deletion of 102 nucleotides was found in the cDNA derived from one plasma specimen. These results suggest that HCV-J is a strain different from the HCV-US and that mutation of the viral genome occurs at as high a frequency as in that of the human immunodeficiency virus.

[A case with chronic hepatitis C who developed liver cirrhosis due to liver dysfunction caused by pegylated interferon plus ribavirin treatment despite negativity of serum HCV RNA, during therapy]

We report a case of chronic hepatitis C in whom liver cirrhosis was later diagnosed following abnormality of ALT levels during pegylated interferon α2a and ribavirin treatment. A 62-year-old woman with chronic hepatitis C was treated with pegylated interferon α2a plus ribavirin for 72 weeks. Her HCV RNA became negative 16 weeks after the start of treatment and continued to be negative for most of the treatment duration. Her AST/ALT, ALP/γ-GTP levels became elevated soon after the initiation of treatment and thereafter remained unchanged. However, most of these levels normalized after the end of treatment. Post-treatment liver biopsy showed liver cirrhosis, probably due to the interferon treatment itself. This unusual therapeutic outcome should be considered if the levels of hepatic dysfunction during interferon treatment are severe.

Platelet-activating cytokines potentially associated with MASLD-induced liver injury significantly decreased following CPAP therapy: A translational study using a fatty liver mouse model

BACKGROUND AND AIM

Patients with obstructive sleep apnea (OSA) and metabolic dysfunction associated steatotic liver disease (MASLD) frequently overlap due to the high prevalence of obesity. This translational study aimed to identify cytokines linking these conditions, beginning with an analysis of fatty liver in mice. Serum cytokine levels upregulated in the fatty liver mice were subsequently examined in human OSA serum samples.

METHODS

Mice were fed a high-fat diet to induce fatty liver. Liver proteins were analyzed using cytokine arrays. Serum samples from seventy (70) OSA patients (with 20 non-MASLD and 50 MASLD, pre- and 6-month post-continuous positive airway pressure [CPAP] therapy) were analyzed for the cytokines identified in the mouse experiment using enzyme-linked immunosorbent assays.

RESULTS

Four platelet-activation chemokines/cytokines (CCL5/RANTES, P-selectin, CXCL4/PF4, and CXCL5/LIX) were upregulated in mice with fatty liver. While serum levels of these factors were not significantly higher in MASLD-OSA compared to non-MASLD-OSA patients, their levels significantly decreased 6 months after the initiation of CPAP therapy, along with a reduction in mean platelet volume. CPAP compliance was significantly associated with a reduction in CCL5 levels. Additionally, a decrease in ALT levels following 6 months of CPAP therapy was significantly associated with CPAP compliance in MASLD-OSA patients.

CONCLUSIONS

While platelet-activation cytokines were not directly implicated in liver injury in MASLD-OSA patients, they decreased with CPAP therapy. CPAP compliance may play a key role in ALT reduction in MASLD-OSA patients independently of body weight changes. CCL5/RANTES may be indirectly associated with liver injury in MASLD-OSA, potentially induced through intermittent hypoxia.