Amino-acid change on the antigenic region B1 of H3 haemagglutinin may be a trigger for the emergence of drift strain of influenza A virus

Sera from 27 children and eight older persons, which had been collected in 1998 and 1999 and showed haemagglutination-inhibition (HI) activity against influenza A/Sydney/5/97 (H3N2) strain, were characterized with a binding assay using chimeric haemagglutinin (HA) proteins between A/Aichi/2/68 (A/AI/68) and A/Sydney/5/97 (A/SD/97) strains. Sera from the young children had a tendency to recognize only the antigenic site B1 of the HA1 region. On the other hand, sera of the older individuals were fully reactive to all antigenic sites of HA1 except antigenic site D. Recent epidemic strains, A/Panama/2007/99 (A/PM/99)-like viruses have differences in amino acids in antigenic sites A, C, and B2 but not B1. However, human antisera obtained even from young children had HI activity to Panama-like viruses. The limited epidemic of A/PM/99-like viruses may have been due to the existence of antibody against B1, which had been produced in response to infection by the A/SD/97-like viruses.     

Small lung tumors with the size of 1cm or less in diameter: clinical, radiological, and histopathological characteristics

BACKGROUND: The detection rate of small nodules in the peripheral lung area is increasing due to the widespread use of CT scanning. However, the radiological and pathological characteristics of very small tumors have not been fully investigated. METHODS: We evaluated 44 lung tumors with the size of 1cm or less in diameter resected from 38 patients (19 men and 19 women, with an average of 62 years) from 1997 through 2001. The clinical records, the findings of high-resolution CT (HRCT) and histopathological features of resected specimens were analyzed. Adenocarcinoma was histologically further subclassified into types A to F according to the Noguchi's classification. RESULTS: Lobectomy was performed in 20 patients, wedge resection in 15 and segmentectomy in 3, respectively. Thirty-two tumors were adenocarcinomas, 4 were squamous cell carcinomas, and eight were atypical adenomatous hyperplasia (AAH), respectively. All carcinoma cases were proved to be stage IA. In adenocarcinoma, type A was detected in 12 tumors, type B in 13, type C in 1, type D in 2, type E in 1, and type F in 3, respectively. Most of AAH and type A showed pure ground-glass attenuation on HRCT scan, whereas types B to F as well as squamous cell carcinoma frequently had malignant CT signs such as lobulation and convergence of peripheral vessels. Lymphatic or vascular invasion was observed in two adenocarcinomas (types D and F) and two squamous cell carcinomas, and HRCT scan of these four tumors showed soft-tissue attenuation occupying more than two-thirds of each nodule. All patients are currently alive without signs of recurrence after a mean follow-up period of 35.5 months. CONCLUSION: Types A and B of adenocarcinoma were the most common histologic types among lung tumors with the size of 1cm or less in diameter. Limited lung resection appears to be an adequate for such small lung tumors in which soft-tissue attenuation consists of less than two-thirds of the nodule on HRCT.     

Signal transduction pathways regulating osteoclast differentiation and function

Journal of Bone and Mineral Metabolism -     

Expression of the receptor for pituitary adenylate cyclase-activating polypeptide (PAC1-R) in reactive astrocytes

We generated transgenic mice that express an enhanced green fluorescent protein (EGFP) under the control of the mouse glial fibrillary acidic protein (GFAP) promoter. In one of the transgenic lines, the green fluorescence of EGFP was undetectable in almost all of the brain regions, including the neocortex, in untreated animals. However, when reactive astrogliosis was induced by cortical stab wounding, the strong fluorescence of EGFP was observed around the needle track but was not found in the corresponding area of the contralateral hemisphere. The EGFP-expressing cells had the morphological features of reactive astrocytes such as thick processes. The EGFP-expressing cells were found to overlap with the astroglial marker GFAP, but not with the microglial marker CD11b or the neuronal marker NeuN. Furthermore, there were some EGFP-expressing cells that expressed vimentin-like immunoreactivity, the specific marker for reactive astrocytes. These results strongly suggest that the EGFP-expressing cells are reactive astrocytes, but not resting astrocytes. Using these transgenic mice, immunostaining for the PAC1 receptor (PAC1-R) was performed. PAC1-R, which is a pituitary adenylate cyclase-activating polypeptide (PACAP)-specific receptor, binds PACAP, which is known to have a wide variety of functions. An immunohistochemical study revealed the localization of PAC1-R in reactive astrocytes visualized with EGFP around the needle track at 5 days postsurgery.     

Demonstration of immunoreactive somatostatin-like substance in villi and decidua in early pregnancy.

With the use of the radioimmunoassay for growth hormone--releasing inhibiting factor (GIF), it was found that measurable amounts of GIF-like substance existed in the chorionic villi and decidua of pregnant women. The indirect immunofluorescent method revealed that the higher intensity of GIF-like immunofluorescence was presented in cytotrophoblasts rather than in syncytiotrophoblasts of the villi and in stromal cells of the decidua.     

Epidemiologic Studies on mumps. II. Prospective, Periodic Surveillance on Mumps in Three Different Areas

Prospective, periodical sero-epidemiological surveillance on mumps was carried out in three different populations in Aichi prefecture. 1) In a newly developed residental quarter full of big apartment buildings, where heavy population density burst has been occurring, mumps has been observed as an endemic disease. Serologically, almost all the children under six years old has experienced mumps infection in such an area. 2) In an old city with stable population dynamics, mumps outbreaks have been taken place pediodically. The results of serosurvey suggested that the periodic outbreaks occurred when more than 60–70% of the children became susceptible, regardless of seasons. 3) In a relatively isolated small town, mumps epidemics has not been observed for many years and when the disease is introduced into the community however, large outbreak develops in the town.     

Attenuation of the activated mammalian target of rapamycin pathway might be associated with renal function reserve by a low-protein diet in the rat remnant kidney model

The mammalian target of rapamycin (mTOR), a regulator of cellular protein synthesis and cell growth, plays an important role in the progression of renal hypertrophy and renal dysfunction in experimental chronic kidney disease models. Because the mTOR activity is regulated by nutrients including amino acids, we tested the hypothesis that the renoprotective effect of a low-protein diet (LPD) might be associated with the attenuation of the renal mTOR pathway. In this study, 5/6 nephrectomized rats were fed an LPD or a normal protein diet (NPD), and a number of rats that were fed an NPD received rapamycin (1.0 mg kg⁻¹ d⁻¹), a specific inhibitor of mTOR. After 6 weeks, renal tissue was collected to evaluate the activity of the mTOR pathway and histologic changes. The phosphorylation of p70S6k, a kinase in the downstream of mTOR, was significantly higher in the NPD-fed rats that showed progressive renal dysfunction than in the sham-operated rats (NPD). The LPD attenuated the excessive phosphorylation of p70S6k concomitant with reduced proteinuria and improved renal histologic changes in the 5/6 nephrectomized rats. The effects of the LPD were similar to the effects of rapamycin. The expression of phosphorylated p70S6k was significantly correlated with proteinuria (r² = 0.63, P < .001), the glomerular area (r² = 0.60, P < .001), and the number of phosphorylated Smad2-positive cells in the glomerulus (r² = 0.26, P < .05) of these rats. These results suggest that the preventive effect of an LPD on the progression of renal failure is associated with attenuation of the activated mTOR/p70S6k pathway in the rat remnant kidney model.     

Association between Dietary Fat Intake and Hyperuricemia in Men with Chronic Kidney Disease

Despite a close relationship between chronic kidney disease (CKD) and uric acid level, few studies have examined the relationship between uric acid level and fat intake by kidney function status. Therefore, we investigated the association between dietary fat intake and hyperuricemia with and without decreased kidney function in males living in Shika Town, Ishikawa Prefecture, Japan. This study included 361 males with a mean age of 60.7 years. Dietary fat and fatty acid intakes were evaluated using the brief-type self-administered diet history questionnaire. Reduced kidney function was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m², while hyperuricemia was defined as a serum uric acid level >7.0 mg/dL. A two-way analysis of covariance showed that saturated fatty acid (p = 0.026), monounsaturated fatty acid (p = 0.014), and polyunsaturated fatty acid (p = 0.022) were significantly lower in the high uric acid group than in the normal uric acid group. In multiple logistic analysis stratified by renal function, lipid intake was negatively associated with hyperuricemia in the low eGFR group. These findings suggest that higher dietary lipid/fatty acid intake may be effective in the prevention and treatment of hyperuricemia in men with CKD.     

Neuroprotective effects of progesterone in traumatic brain injury: blunted in vivo neutrophil activation at the blood-brain barrier

Background

Progesterone (PRO) may confer a survival advantage in traumatic brain injury (TBI) by reducing cerebral edema. We hypothesized that PRO reduces edema by blocking polymorphonuclear (PMN) interactions with endothelium (EC) in the blood-brain barrier (BBB).

Methods

CD1 mice received repeated PRO (16 mg/kg intraperitoneally) or vehicle (cyclodextrin) for 36 hours after TBI. Sham animals underwent craniotomy without TBI. The modified Neurological Severity Score graded neurologic recovery. A second craniotomy allowed in vivo observation of pial EC/PMN interactions and vascular macromolecule leakage. Wet/dry ratios assessed cerebral edema.

Results

Compared with the vehicle, PRO reduced subjective cerebral swelling (2.9 ± .1 vs 1.2 ± .1, P < .001), PMN rolling (95 ± 1.8 vs 57 ± 2.0 cells/100 μm/min, P < .001), total EC/PMN adhesion (2.0 ± .4 vs .8 ± .1 PMN/100 μm, P < .01), and vascular permeability (51.8% ± 4.9% vs 27.1% ± 4.6%, P < .01). TBI groups had similar a Neurological Severity Score and cerebral wet/dry ratios (P > .05).

Conclusions

PRO reduces live pericontusional EC/PMN and BBB macromolecular leakage after TBI. Direct PRO effects on the microcirculation warrant further investigation.