Prediction of left ventricular peak ejection velocity by preceding and prepreceding RR intervals in atrial fibrillation: a new method to adjust the influence between two intervals

In atrial fibrillation, cardiac performance is dependent on both preceding RR (RR-1) and prepreceding RR (RR-2) intervals. However, relative contributions were not well defined. Left ventricular outflow peak ejection velocity (Vpe) was measured by echocardiography from 21 patients. The relation between RR-1 and Vpe could be divided into two zones; steep slope in short RR-1 intervals (< or =0.5 sec) and plateau in long RR-1 intervals (> 0.5 sec). RR-2 had a weak negative association with Vpe. The mean squared correlation coefficient (r2) between RR-2 and Vpe was 0.15 +/-0.13 and improved to 0.29+/-0.21 (p<0.001), when coordinates with RR-1 < or =0.5 sec were excluded. The RR-1 was positively associated with Vpe. The mean r2 between RR-1 and Vpe was 0.52+/-0.17 and improved to 0.72+/-0.11 (p<0.001), when adjusted by RR-2. Simple linear regression analysis showed that mean RR interval, age, fractional shortening (FS), and mean peak velocity were negatively correlated with modified r2 between RR-2 and Vpe. Multiple stepwise regression analysis revealed that mean RR interval (r2=0.32) and FS (r2=0.16) were significant. In summary, simple modification could improve the relationship of both RR-1 and RR-2 with cardiac performance. RR-2 might play a more role in cardiac performance than previously expected, and when cardiac function was impaired.     

Purulent pericarditis caused by group G streptococcus as an initial presentation of colon cancer

Bacterial pericarditis has been recognized as a rare disease since the development of antibiotics. Usually, the disease is associated with underlying conditions or a seeding of infection elsewhere to the pericardium. Here we describe a case of group G streptococcal pericarditis as an initial presentation of colon cancer. A 52-yr-old man was admitted because of dyspnea. An electrocardiogram showed a diffuse ST-segment elevation and a two-dimensional echocardiogram showed a large amount of pericardial effusion. A pericardiocentesis was done and purulent fluid was drained. Group G streptococci was cultured in pericardial fluid. The patient was treated with antibiotics and pericardiostomy with saline irrigation. A colonoscopy revealed a small mass with moderately differentiated adenocarcinoma in rectosigmoid colon. He underwent a mucosectomy and was recovered without any complication.     

Surface expression of P-selectin on platelets is related with clinical worsening in acute ischemic stroke

Platelet activation has a critical role in arterial disorders. In this study, we showed that the upregulation of P-selectin expression on platelets was related with clinical worsening in acute ischemic stroke. We serially (within 24 hr, at 72 hr, and 7 days) measured the expression of P-selectin on platelets in patients with acute ischemic stroke (n=45) and investigated the correlation between their extents and clinical severity of ischemic stroke. A significant relationship between the P-selectin expressions and National Institute of Health Stroke Scale (NIHSS) was observed at 72 hr and 7 days after ischemic stroke onset. Patients with clinical deterioration showed significantly increased expression of P-selectin on platelets as compared to those without deterioration. These results suggest that the P-selectin expression on platelets may contribute to the aggravation of clinical course in acute ischemic stroke. Thus, adequate manipulation of activated platelets is an important therapeutic strategy in acute ischemic stroke.     

Exogenous wild-type p16INK4A gene induces delayed cell proliferation and promotes chemosensitivity through decreased pRB and increased E2F-1 expressions

Human gastric cancer SNU 484 cells express mutant p16, which migrates slower than the wild-type p16. We constructed an expression vector containing human p16 cDNA to evaluate the cytotoxic effects of exogenous p16 expression on SNU 484 cell proliferation and to explore the potential use of p16 in cancer gene therapy. The stable transfectant expressing wild-type p16, showed a 2-fold slower growth rate than mock and non-infected cells through down-regulation of CDK4-dependent kinase activity. When cells were transiently transfected with mock or p16 encoded vector, the mock cells showed larger survival colonies than those of wild-type p16. Furthermore, p16-expressing stable transfectant was readily progressed into cell death by combination with treatment of chemotherapeutic drug in a dose-dependent manner. According to western blot analysis, both decreased expression of pRB and increased expression of E2F-1 may contribute to the susceptibility of cell death. Our data indicate that exogenous wild-type p16 induces delayed cell proliferation and promotes chemo-sensitivity in the gastric cancer cell line, implying the promise of p16 in cancer gene therapy.     

Elastic biodegradable poly(glycolide-co-caprolactone) scaffold for tissue engineering

Cyclic mechanical strain has been demonstrated to enhance the development and function of engineered smooth muscle (SM) tissues, and it would be necessary for the development of the elastic scaffolds if one wishes to engineer SM tissues under cyclic mechanical loading. This study reports on the development of an elastic scaffold fabricated from a biodegradable polymer. Biodegradable poly(glycolide-co-caprolactone) (PGCL) copolymer was synthesized from glycolide and epsilon-caprolactone in the presence of stannous octoate as catalyst. The copolymer was characterized by (1)H-NMR, gel permeation chromatography and differential scanning calorimetry. Scaffolds for tissue engineering applications were fabricated from PGCL copolymer using the solvent-casting and particle-leaching technique. The PGCL scaffolds produced in this fashion had open pore structures (average pore size = 250 microm) without the usual nonporous skin layer on external surfaces. Mechanical testing revealed that PGCL scaffolds were far more elastic than poly(lactic-co-glycolic acid) (PLGA) scaffolds fabricated using the same method. Tensile mechanical tests indicated that PGCL scaffolds could withstand an extension of 250% without cracking, which was much higher than withstood by PLGA scaffolds (10-15%). In addition, PGCL scaffolds achieved recoveries exceeding 96% at applied extensions of up to 230%, whereas PLGA scaffolds failed (cracked) at an applied strain of 20%. Dynamic mechanical tests showed that the permanent deformation of the PGCL scaffolds in a dry condition produced was less than 4% of the applied strain, when an elongation of 20% at a frequency of 1 Hz (1 cycle per second) was applied for 6 days. Moreover, PGCL scaffolds in a buffer solution also had permanent deformations less than 5% of the applied strain when an elongation of 10% at a frequency of 1 Hz was applied for 2 days. The usefulness of the PGCL scaffolds was demonstrated by engineering SM tissues in vivo. This study shows that the elastic PGCL scaffolds produced in this study could be used to engineer SM-containing tissues (e.g. blood vessels and bladders) in mechanically dynamic environments.     

Telangiectatic pulmonary arteriovenous malformation

Telangiectatic pulmonary arteriovenous malformation is defined as a pulmonary arteriovenous malformation involving every segmental artery of at least one lobe of the lung. The authors report a case of telangiectatic pulmonary arteriovenous malformation in the left lower lobe of the lung.     

Effects of Allergina on the Treatment of Otitis Media with Effusions

The number of pediatric patients with recurrent otitis media with effusions (ROMEs) is increasing because of the frequency of recurrence. The herbal combination Allergina is used for inflammatory-disease treatment in the Republic of Korea; in our study, the patients with ROME were treated with either Allergina (11 ears) or antibiotics (13 ears). We analyzed the levels of cytokines in middle-ear effusions (MEEs) and compared these levels in the Allergina-treated patients with those in the antibiotics-treated patients. The mean levels of interleukin (IL)-2 and IL-4 in MEEs were significantly higher in the Allergina-treated patients than in the antibiotics-treated patients, whereas levels of IL-1, IL-6, IL-8, and tumor necrosis factor (TNF)- in MEEs were significantly lower in the Allergina-treated patients than in the antibiotics-treated patients. Clinical signs of ROME disappeared markedly after all the patients were given an oral administration of Allergina. Our experimental studies provide evidence that Allergina may be beneficial in the treatment of ROME by regulating cytokine production.     

Quantities of receptor molecules for colony stimulating factors on leukocytes in measles

We analyzed the comparative amounts of granulocyte-colony stimulating factor (G-CSFr) and granulocyte macrophage CSF (GM-CSFr) receptors expressed on neutrophils and monocytes in measles patients to investigate the role of these CSFrs in the development of leukopenia including neutropenia and monocytopenia in measles. EDTA-anticoagulated peripheral blood of 19 measles patients, 10 children with other infections showing leukopenia and 16 children with normal complete blood cell counts (CBC)s were analyzed using flow cytometry and QuantiBRITE. The leukocyte (5260 +/- 2030/uL vs. 9900 + 2680/uL, p=0.000), neutrophil (2580 +/- 960/uL vs. 4250 +/- 2750/uL, p=0.024) and the lymphocyte counts of measles patients (1810 +/- 1430/uL vs. 4530 +/- 3450/uL, p= 0.006) were lower than in the normal controls. The neutrophils of measles patients expressed similar amounts of G- CSFr (1858 +/- 355) as normal children (1764 +/- 477, p= 0.564) and leukopenic patients (1773 +/- 673, p=0.713), but lower levels of GM-CSFr (535 +/- 118) than normal children (957 +/- 344, p=0.000) and leukopenic patients (832 +/- 294, p=0.002). The monocytes of measles patients expressed similar amounts of G-CSFr (916 +/- 336) and GM-CSFr (3718 +/- 906) as normal children (1013 +/- 391 and 4125 (2645, p > 0.05) but less than leukopenic patients (1454 +/- 398 and 5388 +/- 806, p > 0.05). The neutrophil and monocyte counts of measles patients did not correlate with the amount of G-CSFr or GM-CSFr expressed on neutrophils or monocytes (p > 0.05), but in the normal children, the monocyte count correlated with the levels of GM-CSFr on monocytes (r=0.951, p=0.049). In conclusion, neutropenia is one of the more important characteristics of measles patients, which could be due to the decreased GM-CSFr expression on neutrophils. However, the monocytopenia found in measles patients is not due to the decreased expression of CSFr on the monocytes.     

Mechanical control of extracellular space in rabbit atria: an intimate modulator of the translocation of extracellular fluid and released atrial natriuretic peptide

We have previously shown that extracellular fluid (ECF) is translocated by atrial contraction. Following on from this finding we have proposed a two-step sequential mechanism for the regulation of stretch-activated secretion of atrial natriuretic peptide (ANP): myocytic release of ANP into the surrounding paracellular space followed by the translocation of ECF with the released ANP into the bloodstream. This latter step is induced by atrial contraction, and is therefore controlled by atrial workload. However, the mechanism that regulates the changes in translocation of the ECF has not been defined. To define the relationship between the atrial workload, ECF translocation, size of the extracellular space (ECS) and ANP secretion, experiments have been performed in isolated perfused beating rabbit atria. Atrial workload, transendocardial translocation of the ECF and the secretion of ANP were quantified. Changes in the size of the atrium and the ECS were determined by a newly developed methodology in the beating atria. Atrial workload determined the translocation of the ECF and released ANP with waning of the translocation at higher myocardial workloads. Atrial workload inversely determined the size of the atrium and the ECS. The latter directly determined the translocation of the ECF in terms of atrial workload. From these data we suggest that the size of the ECS is an intimate modulator of the translocation of the ECF and released ANP, and that the phenomenon of waning of the transendocardial translocation that appeared at higher atrial workloads is closely related to the shrinkage of the ECS.     

Comparison between conventional cystometry and stimulated filling cystometry by diuretics in a neurogenic bladder after spinal cord injury

OBJECTIVE: To determine in the neurogenic bladder whether cystometry performed under near physiologic condition by filling stimulation using diuretics reveals different findings compared with conventional cystometry (CMG). DESIGN: One group of subjects from a university teaching hospital was tested in two conditions. The maximum detrusor pressure (MPdet) and compliance of the bladder in CMG and furosemide-stimulated filling cystometry (FCMG) were compared in 27 patients with neurogenic bladder after spinal cord injury. The MPdet was estimated. Compliance was calculated. For CMG, the bladder was filled. FCMG was performed 3 hr after CMG. For FCMG, furosemide was injected after infusion of normal saline. Recording intravesical pressure started after emptying the bladder immediately after furosemide injection. RESULTS: Significant differences were found between CMG and FCMG in hyperreflexic neurogenic bladders with respect to a decrease in MPdet and increase in compliance with FCMG. However, there were no significant differences in MPdet and compliance in hyporeflexic or areflexic neurogenic bladders between the two techniques. CONCLUSION: We have found that FCMG is useful in evaluating both genuine MPdet and compliance in patients with hyperreflexic neurogenic bladder dysfunction. FCMG provides more reliable information on detrusor characteristics than CMG in hyperreflexic neurogenic bladder. We suggest that FCMG is an alternative, effective, and near physiologic diagnostic method, having short assessment time for improving evaluation of the detrusor characteristics of hyperreflexic neurogenic bladder.