Inflammation of the liver causes mutations in duck hepatitis B virus genome

To investigate whether hepatitis causes mutation in the viral genome, DNA sequences in the pre-core region of duck hepatitis B virus (DHBV) DNA were analyzed in both ducks with hepatitis and without hepatitis. Five DHBV carrier ducks were injected with DHBV particle proteins purified from duck serum with Freund’s complete adjuvant (FCA) intrahepatically from 14 day posthatch for 9 weeks (immunized group). Serum was drawn at the end of the 1st and 4th week after the 1st injection of DHBV particle protein and ducks were killed at the end of the 9th week to obtain the liver. Another five ducks without treatment were used as controls. All ducks of the immunized group showed moderate to severe hepatitis at the 9th week. All ducks in the immunized group showed one mutation except one duck that showed two mutations only at the 9th week. Mutations were observed in the 5th, 13th, 21st, 22nd, and 28th codon of the precore region. All of them were point mutation at the 3rd base in the triplets. The frequency of mutation was different in each duck from 20% to 60% but not 100%. There was no mutations in ducks in control group. These results suggest that hepatitis causes mutation in the pre-core lesion genome of duck hepatitis B virus.     

Effect of synthetic porcine neuropeptide Y (NPY) on splanchnic blood flows and Exocrine pancreatic secretion in dogs

This study examined the effect of synthetic porcine neuropeptide Y on the splanchnic blood flows and the exocrine pancreatic secretion in dogs. Graded doses of neuropeptide Y (0.1–5 g/kg, intravenous) caused dose-dependent reduction of the secretin-stimulated exocrine pancreatic secretion and of the blood flows in the superior mesenteric artery, the portal vein, and the pancreatic tissue. Neuropeptide Y at 5 g/kg reduced the blood flows to 45.9±13.3% (superior mesenteric artery), 63.0±10.5% (portal vein), and 77.9±4.8% (pancreatic tissue), respectively. This dose also reduced secretin-stimulated pancreatic juice volume and CCK-8 plus secretin-stimulated protein output to 65.2±9.3 and 63.3±14.0%, respectively. This study shows a potent vasoconstrictor effect of neuropeptide Y on splanchnic vessels. Neuropeptide Y also inhibited exocrine pancreatic secretion in a significant correlation with the reduction in pancreatic tissue blood flow, which suggests that reduction in the blood flow may be one of the possible mechanisms of the inhibitory action of neuropeptide Y on exocrine secretion.This work was supported by a grant from the Ministry of Education, Japan (A-61440060).     

What is the most appropriate variable for estimation of mean pulmonary capillary wedge pressure by transesophageal pulsed Doppler echocardiography?

Although left ventricular (LV) inflow and pulmonary venous (PV) flow variables estimated by transesophageal Doppler echocardiography (TEE) reflect pulmonary capillary wedge pressure (PCWP), they are also affected by changes in cardiac function. The purpose of the present study was to detect the most appropriate variable for the estimation of PCWP by TEE in patients (pts) with ischemic heart disease. Several variables of LV inflow and left upper PV flow were compared with PCWP in 36 pts (six with angina pectoris and 30 with old myocardial infarction). Early diastolic flow (E) and atrial contraction flow (A) were used as LV inflow, while systolic forward flow (X), diastolic forward flow (Y) and atrial contractile reversal flow (z) were used as PV flow. The peak velocity of each flow wave (Ep, Ap, Xp, Yp, and Zp) and the time-velocity integral (Ei, Ai, Xi, Yi, and Zi) were measured. The ratio of Ep to Ap (Ep/Ap), Ei to Ai (Ei/Ai), Xp to Yp (Xp/Yp), Xi to Yi (Xi/Yi), Zp to Ap (Zp/Ap), Zi to Ai (Zi/Ai) and the systolic fraction of PV forward flow were calculated. Among these variables, the Zi/Ai ratio was most strongly correlated with PCWP (R=0.80). The Zi/Ai ratio may not be influeced by atrial function because the augmentation of atrial pump function increases Zi as well as Ai, and this may be one reason why the ratio correlated well with PCWP.Conclusion: The Zi/Ai ratio is a new useful variable for estimating PCWP by TEE.Abbreviations Ap peak velocity of left ventricular inflow during atrial contraction - Ep peak velocity of left ventricular inflow during early diastole - Yp peak velocity of diastolic pulmonary venous forward flow - Xp peak velocity of systolic pulmonary venous forward flow - Zp peak velocity of pulmonary venous reversal flow during atrial contraction - Ai time-velocity integral of left ventricular inflow during atrial contraction - Ei timevelocity integral of left ventricular inflow during early diastole - Yi time-velocity integral of diastolic pulmonary venous forward flow - Zi time-velocity integral of pulmonary venous reversal flow during atrial contraction - Xi time-velocity integral of systolic pulmonary venous forward flow     

Fatal eosinophilic heart disease in a child with neurofibromatosis-1 complicated by acute lymphoblastic leukemia

We present a pediatric case of neurofibromatosis-1 (NF-1) complicated by acute lymphoblastic leukemia and hypereosinophilia, which caused multiple end-organ damage. Although clinical symptoms such as fever and coughing were noted only 1 week before admission, the condition deteriorated rapidly with a fatal outcome prior to antileukemic therapy. A postmortem examination demonstrated extensive endomyocardial fibrosis with thrombotic occlusion and recanalization of the coronary arteries. Leukemic cell infiltration was not seen in the cardiac tissue. When eosinophilia is diagnosed in patients with NF-1, eosinophilic end-organ damage, particularly cardiac involvement, in addition to hematological malignancies, should be screened for in order to start medical treatment at the early stage of the disease.     

Change in the membranous lipid composition accelerates lipid peroxidation in young rat hearts subjected to 2 weeks of hypoxia followed by hyperoxia.

BACKGROUND: The effects of chronic hypoxia on cardiac membrane fatty acids and on lipid peroxidation were examined, as well as the effect of l-carnitine (LCAR), which suppresses lipid peroxidation, on this process. METHODS AND RESULTS: Four-week-old Sprague-Dawley rats were exposed to 10% oxygen for 14 days ("Hypoxia"), and then to 100% oxygen for 12 h (O2). LCAR (200 mg/kg) was administered by intraperitoneal injection daily for 2 weeks. Fatty acid composition, malondialdehyde (MDA) as a lipid peroxidation product, and antioxidants (superoxide dismutase (SOD), glutathione peroxidase and catalase) were measured. The concentration of linoleic acid was lower, and that of docosahexaenoic acid, which has more double bonds than linoleic acid, was increased in hypoxic hearts. SOD activity decreased in hypoxia, whereas MDA was unchanged, but significantly increased in "Hypoxia"+O2. LCAR reduced the increase in MDA, and had no effect on SOD activity or fatty acid composition. The administration of LCAR caused an increase in the ventricular levels of acetylcarnitine. CONCLUSIONS: These results suggest that chronic hypoxia changes the cardiac fatty acid composition of juvenile rats to fatty acids that contain more double-bonds and reduce SOD activity, and that lipid peroxidation was augmented by exposure to oxygen.     

A rare tumor in the adrenal region: neuron-specific enolase (NSE)-producing leiomyosarcoma in an elderly hypertensive patient

A 73-year-old Japanese woman was referred for examination of right flank pain and progressive hypertension. Abdominal CT incidentally detected a right adrenal mass 8 cm in size. The tumor exhibited isodensity by CT and contained high-intense lesion by T2-weighted MRI. Scintigraphy with (131) I-metaiodobenzylguanidine and (131) I-adosterol showed no abnormal uptake by whole body scan. Positron emission tomography scan with (18) F-2-fluoro-D-deoxyglucose demonstrated an exclusive uptake in the right adrenal mass. Adrenocortical hormone levels and catecholamine secretion were within normal range; however, the level of serum neuron-specific enolase (NSE) was found to be markedly high. After controlling systemic blood pressure with an alpha1-blocker, the right adrenal tumor was surgically removed, along with the right kidney and inferior vena cava which adhered to it. The tumor was pathologically proven to be leiomyosarcoma, which was immunohistochemically positive with alpha-smooth muscle actin and negative with CD57, S-100 and c-kit proteins. Notably, NSE protein was massively expressed in the resected tumor. After surgery blood pressure was controlled with regular medication and serum NSE levels have since normalized. The possibility of leiomyosarcoma should be kept in mind in adrenal incidentalomas with rapid growth and atypical radiological images. Our findings suggest that circulating NSE levels may be clinically useful for early detection of recurrence.     

Drilling dimension effects in early stages of osseointegration and implant stability in a canine model

Background

This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols.

Material and Methods

Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques were: until 3.75 mm (regular-group); and until 4.0 mm diameter (overdrilling-group) for both implant designs. At 2 and 4 weeks, samples were retrieved and processed for histomorphometric analysis. For torque and BIC (bone-to-implant contact) and BAFO (bone area fraction occupied), a general-linear model was employed including instrumentation technique and time in vivo as independent.

Results

The insertion torque recorded for each implant design and drilling group significantly decreased as a function of increasing drilling diameter for both implant designs (p<0.001). No significant differences were detected between implant designs for each drilling technique (p>0.18). A significant increase in BIC was observed from 2 to 4 weeks for both implants placed with the overdrilling technique (p<0.03) only, but not for those placed in the 3.75 mm drilling sites (p>0.32).

Conclusions

Despite the differences between implant designs and drilling technique an intramembranous-like healing mode with newly formed woven bone prevailed. Key words: Histomorphometry, biomechanical, in vivo, initial stability, insertion torque, osseointegration.