Etiology of severe sensorineural hearing loss in children: independent impact of congenital cytomegalovirus infection and GJB2 mutations

BACKGROUND: Sensorineural hearing loss (SNHL) is the most common congenital disease. Longitudinal studies of infants with congenital cytomegalovirus (CMV) infection have demonstrated an association between CMV and SNHL. However, because of the lack of suitable neonatally collected specimens, the proportion of CMV-associated SNHL has not been defined, nor has the relationship between CMV and the major genetic causes of SNHL, such as mutations in the GJB2 gene. METHODS: Sixty-seven children with severe SNHL were analyzed for CMV and human herpesvirus 6 (HHV-6) infections and for GJB2 mutations. DNA specimens were prepared from dried umbilical cords, which are available for everyone born in Japan. Four children with typical symptomatic infection at birth served as positive control subjects. RESULTS: Congenital CMV infection and GJB2 mutations were identified in 15% and 24% of the patients, respectively. HHV-6 was not detected. All children with CMV-associated cases developed SNHL before they were 2 years old. Most children with CMV-associated SNHL had no obvious clinical abnormality at birth, and their viral loads were lower than those of symptomatic children. CONCLUSIONS: Congenital CMV infection is an important cause of severe SNHL, and it has an incidence comparable to that of GJB2-associated SNHL.     

Life style-related diseases of the digestive system: endocrine disruptors stimulate lipid accumulation in target cells related to metabolic syndrome

Many reports indicated that endocrine disruptors (EDs) affect several hormonal functions in various living things. Here, we show the effect of EDs on lipid accumulation in target cells involved in the onset of metabolic syndrome. Treatment with nonylphenol and bisphenol A, typical EDs, stimulated the accumulation of triacylglycerol in differentiated adipocytes from 3T3-L1, preadipocytes, in time- and concentration-dependent manners. Up-regulation of gene expressions involved in lipid metabolism and metabolic syndrome were observed in adipocytes treated with EDs. Similarly, stimulatory effects of EDs were also observed on the human hepatoma cell line HuH-7. These observations indicate that exposure to EDs stimulates the lipid accumulation in target cells involved in the metabolic syndrome and may cause the dysfunction of those cells, resulting in induction of metabolic syndrome.     

Ancient history of Indian pharmacy

The study of the ancient history of Indian medicine has recently been revived due to the publication of polyglot translations. However, little is known of ancient Indian pharmacy. Archaeological evidence suggests the Indus people lived a settled life approximately in 2500 B.C. Their cities were enjoying the cleanest and most hygienic daily life with elaborate civic sanitation systems. The whole conception shows a remarkable concern for health. Then, the early Aryans invaded India about 1500 B.C. and the Vedic age started. The Rgveda texts contain the hymns for Soma and those for herbs. The term Ayurveda (i.e., science of life) is found in some old versions of both Ramāyana and Mahābhārata and in the Atharvaveda. Su?ruta had the credit of making a breakthrough in the field of surgery. The Ayurveda, a work on internal medicine, gives the following transmission of sages: Brahmā-->Daksa-->Prajāpati-->A?ivinau-->Indra-->Caraka. On the other hand, the Su?ruta-samhitā, which deals mainly with surgical medicine, explains it as follows; Indra-->Dhanvantari-->Su?ruta Both Caraka and Su?ruta were medical doctors as well as pharmacists, so they studied more than 1000 herbs thoroughly. The Ayurveda had been used by his devotees for medical purposes. It eventually spread over Asia with the advanced evolution of Buddhism.     

Reevaluation of trkA expression as a biological marker of neuroblastoma by high-sensitivity expression analysis--a study of 106 primary neuroblastomas treated in a single institute

Background/Purpose

It has previously been shown that neuroblastomas with favorable prognosis often express a high level of nerve growth factor receptor trkA. We performed an expression analysis of trkA in 106 NB samples based on the quantitative real-time polymerase chain reaction (PCR) and reevaluated the prognostic power of trkA.

Materials and methods

A total of 106 primary tumors from NB patients treated from 1988 to 2009 were analyzed. MYCN was amplified in 13 cases. TaqMan probe method was used for quantitative PCR. Primers and probes were designed to detect trkA I and trkA II, but not the oncogenic splice variant trkA III.

Results

Expression analysis by real-time PCR revealed a wide range of expression levels of trkA within neuroblastoma tissues. Extremely low levels of trkA that were undetectable by semiquantitative PCR were able to be quantified by this method. trkA was predominantly expressed in tumors with favorable outcome. Further analysis of trkA expression was performed in a cohort excluding mass-screened neuroblastomas. Strikingly, multivariate analysis containing age, MYCN status, and trkA expression identified trkA as the only variable that independently predicts the prognosis of the 44 patients who presented clinically.

Conclusion

High-resolution expression analysis targeting trkA and trkA II may add more statistical power on trkA as a biological marker.     

ATPase activity of KaiC determines the basic timing for circadian clock of cyanobacteria

Self-sustainable oscillation of KaiC phosphorylation has been reconstituted in vitro, demonstrating that this cycle is the basic time generator of the circadian clock of cyanobacteria. Here we show that the ATPase activity of KaiC satisfies the characteristics of the circadian oscillation, the period length, and the temperature compensation. KaiC possesses extremely weak but stable ATPase activity (15 molecules of ATP per day), and the addition of KaiA and KaiB makes the activity oscillate with a circadian period in vitro. The ATPase activity of KaiC is inherently temperature-invariant, suggesting that temperature compensation of the circadian period could be driven by this simple biochemical reaction. Moreover, the activities of wild-type KaiC and five period-mutant proteins are directly proportional to their in vivo circadian frequencies, indicating that the ATPase activity defines the circadian period. Thus, we propose that KaiC ATPase activity constitutes the most fundamental reaction underlying circadian periodicity in cyanobacteria.     

Pharmacokinetics of 5-FU after S-1 oral administration for adjuvant chemotherapy in gastric cancer patients

We studied the pharmacokinetics of 5-FU after S-1 oral administration at the usual dose (80 mg/m2) for adjuvant chemotherapy in 13 advanced gastric cancer patients (Stage II, III), and at a decreased dose (60 mg/m2) for adjuvant or combined chemotherapy in 13 advanced gastric cancer patients. Pharmacokinetic parameters of 5-FU in the serum were as follows: Cmax, 159 .9 2+/-45.2 ng/mL, Tmax, 2.17+/-0.58 h;T1/2, 3.13+/-2.88 h; and AUC(0-8), 768.0+/-260.8 ng h/mL in the patients with the usual dose, and Cmax, 117.3+/-55.1 ng/mL; Tmax, 2.62+/-0.9 6 h; T1/2, 3.09+/-1.9 5 h and AUC(0-8), 565.9+/-216.8 ng h/mL in the patients with the decreased dose. No difference in AUC was observed between operative methods. Adverse events of more than grade 3 were recognized in 7 patients, and AUC of 6 patients were more than 800 ng h/mL. The plasma concentration of 5-FU was quite different between patients. The difference of Cmax and AUC was 3-4 times. It was concluded that we must pay attention to individual differences in the plasma concentration of 5-FU in postoperative gastric cancer patients when S-1 would be administered.     

Different effects of point mutations within the B-Raf glycine-rich loop in colorectal tumors on mitogen-activated protein/extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase and nuclear factor kappaB pathway and cellular transformation

Recently, mutations in the B-Raf gene have been identified in a variety of human cancers, such as melanoma and colorectal carcinoma, and more than 80% of the B-Raf mutations have been V599E. Although other mutations have been reported, their functional consequences are poorly understood. In our earlier study, we demonstrated that colon tumor-associated B-Raf mutations within the kinase activation segment are not necessarily associated with an increase in mitogen-activated protein/extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase (MEK/Erk) or nuclear factor kappaB (NFkappaB) signaling activity or in NIH3T3-transforming ability. In this study, we examined the effect of colon tumor-associated mutations within the B-Raf glycine-rich loop (G loop) on MEK/Erk and NFkappaB signaling and on the transformation of NIH3T3 fibroblasts or IEC-6 intestinal epithelial cells. Of the six G loop mutations examined, only the B-Raf G468A significantly increased MEK/Erk and NFkappaB signaling and NIH3T3 transformation. Only this mutation induced transformed phenotypes of IEC-6 cells. In contrast, the B-Raf G468E mutation significantly decreased MEK/Erk signaling and NIH3T3 transformation and had no effect on NFkappaB signaling. The B-Raf F467C mutation moderately elevated MEK/Erk signaling and NIH3T3 transformation. The other three B-Raf mutations, R461I, I462S, and G463E, did not increase MEK/Erk or NFkappaB signaling or NIH3T3 transformation. Except for F467C, none of the tumors with B-Raf mutations examined in this study had K-Ras mutations. These results suggest that some of the B-Raf G loop mutations reported in colorectal tumors do not increase kinase or transforming activities but might contribute to carcinogenesis via other mechanisms or be irrelevant to carcinogenesis.     

Cyclin G2 dysregulation in human oral cancer

Using expression microarray, we have previously shown that human cyclin G2 (hCG2) is significantly down-regulated in laser capture microdissected oral cancer epithelia. Western analysis showed detectable hCG2 protein in normal (2 of 2) but not in malignant (4 of 4) oral keratinocyte cell lines. Immunohistochemistry analysis done on oral cancers showed that normal oral mucosa (100%, 12 of 12) and 69.1% (47 of 68) of dysplastic oral epithelia expressed readily detectable hCG2 in the nuclei. However, only 11.1% of oral cancer epithelia (14 of 126) showed mild hCG2 nuclear staining. Interestingly, of the oral cancers devoid of nuclear hCG2 (112 cases), 58 cases (52%) showed cytoplasmic hCG2 immunostaining, whereas the other 54 cases (48%) exhibited neither nuclear nor cytoplasmic hCG2 staining. In vitro functional study by ectopic restoration of hCG2 expression in the human malignant squamous cell carcinoma (SCC) line SCC15 resulted in a significant inhibition of cellular proliferation (P < 0.001) and colony formation (P < 2 x 10(-5)) with increased population of G(1) phase and decreased in S phase (P < 0.01). Furthermore, stable down-regulation of hCG2 by short interference RNA-based gene silencing in immortalized normal oral keratinocytes resulted in enhanced cell growth with increase in S and prominently in G(2) phase. Because hCG2 has been implicated as a negative regulator in cell cycle progression, our results support that hCG2 dysregulation may play an important role in epithelial transformation and the early stages of human oral cancer development.     

A case of generalized hypoxic brain damage following traumatic brain damage

In forensic autopsy cases, transient brain hypoxia can be induced by cardiac arrest, hypovolemic shock, and other conditions with severe circulatory failure. Although cortical laminar necrosis in watershed areas between territories of the major cerebral arteries is occasionally seen, cases with global hypoxic damage to the brain is rare, because patients with irreversible severe brain damage rarely survive for more than a few days. In this report we describe autopsy results for an injury victim who survived unconscious for approximately 4 weeks after admission. Macroscopic thinning of the gray matter and uniformly cheesecake-like cloudy changes in white matter were observed. Microscopically, cortical laminar necrosis was observed in all lobes of the cerebrum, and massive gliosis was diffused throughout the white matter. We speculate that traumatic brain damage, continuous hypoxemia, and many other factors induced these characteristic pathological changes during the long time interval from brain damage to death.