Pros and cons of chest wall reconstruction using prosthetic meshes in a two-layer fashion

A 46-year-old woman with giant chondrosarcoma of the sternum underwent wide full-thickness resection of the anterior chest wall, which included the pericardium and lung. The free rectus abdominus musculocutaneous flap was transplanted onto prosthetic meshes placed in two layers. While stability and esthetic effect were both good, the subsequent infection in the space between the two meshes prolonged for one month. As a result, the space was closed with an omentum flap. As a consequence, we recommend one-stage omentopexy to prevent the space problem between the two meshes.

Escherichia coli cells penetrated by chrysotile fibers are transformed to antibiotic resistance by incorporation of exogenous plasmid DNA

A suspension of recipient Escherichia coli cells in stationary phase, chrysotile asbestos, and pUC18 donor DNA spread over the surface of a Luria-Bertani agar plate using a streak bar several times, resulted in intracellular uptake of the plasmid DNA by the E. coli cells. The transformation efficiency was highest with a duration of cell exposure to chrysotile of more than 60 s and an agar concentration of 2%. To improve chrysotile-mediated transformation efficiency, we systematically optimized various conditions and parameters. In comparison to chrysotile exposure without cations, exposure with cations produced up to 100-fold more transformants. Optimized conditions resulted in 10(6) transformants/ micro g pUC18 DNA. The drastic physical change due to 'quick drying on the surface of the agar plate' when cells were exposed to chrysotile, was essential for chrysotile-mediated transformation. We suggest that DNA uptake mediated by chrysotile asbestos is the result of a mechanical physical transformation of E. coli, since the E. coli cells are not chemically competent. Electron microscopy of cells exposed to chrysotile suggested penetration of the E. coli membrane by chrysotile fibers. It is suggested that E. coli transformation by the plasmid DNA was the result of penetration by chrysotile fibers to which plasmid DNA is bound or adsorbed.

Comparative biochemical studies of carotenoids in catfishes

The carotenoids of 12 species of Siluriformes fishes (eight families) were investigated from a comparative biochemical point of view. The patterns of carotenoids in catfishes belonging to the family Siluridae were quite different from those of the other seven families of catfishes (Bagridae, Amblycipitidae, Clariidae, Plotosidae, Ictaluridae, Callichthyidae and Malapteruridae). 7, 8-Dihydro-beta-carotene; 7, 8, 7', 8'- and 7, 8, 9, 10-tetrahydro-beta-carotene; (3R)-7', 8'-dihydro-beta-cryptoxanthin; 7, 8-dihydrolutein A; 7, 8-dihydrolutein B; parasiloxanthin; 7', 8'-dihydroparasiloxanthin; and 4 or 4'-hydroxyparasiloxanthin were characteristic carotenoids found in only one family, Siluridae, and these carotenoids accounted for 24-60% of total carotenoids. In catfishes belonging to the other seven families except Siluridae, the carotenoid patterns were very similar and the most predominant carotenoid was zeaxanthins (23-56%).

Magnetic superstructure in the two-dimensional quantum antiferromagnet SrCu2(BO3)2

We report the observation of magnetic superstructure in a magnetization plateau state of SrCu2(BO3)2, a frustrated quasi-two-dimensional quantum spin system. The Cu and B nuclear magnetic resonance (NMR) spectra at 35 millikelvin indicate an apparently discontinuous phase transition from uniform magnetization to a modulated superstructure near 27 tesla, above which a magnetization plateau at 1/8 of the full saturation has been observed. Comparison of the Cu NMR spectrum and the theoretical analysis of a Heisenberg spin model demonstrates the crystallization of itinerant triplets in the plateau phase within a large rhomboid unit cell (16 spins per layer) showing oscillations of the spin polarization. Thus, we are now in possession of an interesting model system to study a localization transition of strongly interacting quantum particles.

Superconductivity and magnetic fluctuations in Cd(2))Re(2)O(7) via Cd nuclear magnetic resonance and re nuclear quadrupole resonance

We report Cd nuclear magnetic resonance (NMR) and Re nuclear quadrupole resonance (NQR) studies on Cd(2)Re(2)O(7), the first superconductor among pyrochlore oxides (T(c) approximately 1 K). The Re NQR spectrum at zero magnetic field below 100 K rules out any magnetic or charge order. The spin-lattice relaxation rate below T(c) exhibits a pronounced coherence peak and follows the weak-coupling BCS theory with nearly isotropic energy gap. The results of Cd NMR point to a moderate ferromagnetic enhancement at high temperatures followed by a rapid decrease of the density of states below the structural transition temperature of 200 K.

A case of apolipoprotein C-II deficiency with coronary artery disease

A 56-year-old male with apolipoprotein C-II deficiency experienced a myocardial infarction without pancreatitis. A coronary angiogram showed complete occlusions of both the right and circumflex coronary arteries. His serum lipid levels were as follows: fasting total cholesterol 3.15 mmol/l; postprandial total cholesterol 3.62 mmol/l; fasting triglycerides 1.46 mmol/A; postprandial triglycerides 6.14 mmol/l; fasting high-density lipoprotein-cholesterol 0.47 mmol/l; and postprandial high-density lipoprotein cholesterol 0.36 mmol/l. His fasting level of plasma apolipoprotein C-II was 0.005 g/l, but his plasma levels of other apolipoproteins were within normal ranges. A DNA sequence analysis of the apolipoprotein C-II gene showed no mutations in exon 1, 2, 3, or 4, where most gene mutations related to apolipoprotein C-II deficiency occur. We report this patient's very rare heterozygous apolipoprotein C-II deficiency with coronary artery disease. Although this patient had some risk factors for coronary artery disease, coronary atherosclerosis in this patient might have occurred as a result of lipoprotein abnormalities caused by at least one mutation in the apolipoprotein C-II gene.

Coronary endothelial dysfunction in the insulin-resistant state is linked to abnormal pteridine metabolism and vascular oxidative stress

OBJECTIVES

We investigated whether abnormal pteridine metabolism is related to coronary endothelial dysfunction in insulin-resistant subjects.

BACKGROUND

Depletion of tetrahydrobiopterin (BH(4)) and elevation of the 7,8-dihydrobiopterin (BH(2)) (activating and inactivating cofactors of nitric oxide synthase [NOS], respectively) contribute to impairment of NO-dependent vasodilation through reduction of NOS activity as well as increased superoxide anion generation in insulin-resistant rats.

METHODS

Thirty-six consecutive nondiabetic, normotensive and nonobese subjects with angiographically normal coronary vessels were studied. Traditional coronary risk factors, plasma pteridine levels, activities of erythrocyte dihydropteridine reductase (DHPR), the recycling enzyme that converts BH(2) to BH(4) and lipid peroxide (LPO) levels were measured and coronary endothelial function was assessed with graded infusions of acetylcholine (ACh).

RESULTS

When we divided patients into tertiles based on insulin sensitivity, we observed stepwise decreases in the maximal ACh-induced vasodilation and plasma BH(4)/7,8-BH(2) ratio, and increases in coronary LPO production as insulin sensitivity decreased. The ACh-induced vasodilation was positively correlated with insulin sensitivity, BH(4)/7,8-BH(2) ratio and DHPR activity. Furthermore, BH(4)/7,8-BH(2) was inversely correlated with DHPR activity and insulin sensitivity. In multiple stepwise regression analysis, BH(4)/BH(2) was independently related to ACh-induced vasodilation and accounted for 39% of the variance. However, no significant correlation existed between other traditional risk factors and BH(4)/7,8-BH(2).

CONCLUSIONS

These results indicate that both abnormal pteridine metabolism and vascular oxidative stress are linked to coronary endothelial dysfunction in the insulin-resistant subjects.

Thymidylate synthase and dihydropyrimidine dehydrogenase activities in non-small cell lung cancer tissues: relationship with in vitro sensitivity to 5-fluorouracil

We examined enzymatic activities of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) in non-small cell lung cancer (NSCLC) tissues to determine the relationship to tumor sensitivity to 5-fluorouracil (5-FU). TS and DPD activities were measured in 60 surgically resected primary NSCLC tissues using a TS-binding assay and a radioenzyme assay, respectively. In vitro tumor sensitivity to 5-FU was assayed using a collagen gel droplet embedded culture drug test (CD-DST). DPD activities slightly correlated with in vitro sensitivity to 5-FU (r=0.402,P=0.013), such that tumors with higher DPD activity were more resistant to 5-FU. In contrast, no correlation was observed in TS activities. Thus, it was suggested that only DPD activity in NSCLC tissues is a potential indicator in predicting tumor sensitivity to 5-FU. Based on these results, further study is needed to evaluate the clinical significance of these enzymes in 5-FU-based chemotherapy for patients with NSCLC.

Japanese spotted fever associated with multiorgan failure

A 49-year-old man was admitted to our hospital, with a diagnosis of multiple organ failure, on June 10, 2000. Physical examination revealed high fever, generalized maculopapular erythema, and an eschar on his lower leg. Laboratory findings revealed severe renal and liver dysfunction, disseminated intravascular coagulation (DIC), and markedly elevated soluble interleukin 2-receptor (sIL2-R) level (>10 000 U/ml). Administration of minocycline was started immediately, with a diagnosis of rickettsial infection. Simultaneously, anti-thrombin III and heparin were started to treat the DIC, and hemodialysis was also initiated. However, the day after admission, his consciousness level lapsed, to the level of coma, and blood pressure was less than 60 mmHg, indicating shock. Therefore, 500 mg of methylprednisolone was administered once; as a result, rapid pyretolysis and improvement of consciousness disturbance were achieved. Laboratory data indicative of inflammation gradually improved after a few days. Hemodialysis was required ten times. During the recovery period, the level of specific IgM antibody against Rickettsia japonica increased to x2560, and he was diagnosed as having Japanese spotted fever. On July 11, he was discharged without sequelae. The course in our patient was very severe, and treatment with minocycline alone may have resulted in a fatal outcome. The level of sIL2-R, which is produced by activated lymphocytes, was markedly increased. Therefore, markedly elevated lymphocyte activation and hypercytokinemia may have been present on admission. The short-term steroid therapy may have been effective in inhibiting the excessive activation of lymphocytes in the critical stage. In the severe form of Japanese spotted fever with organ failure, combination therapy with minocycline and short-term steroids may be very useful.

The healing process of infarct-related plaques. Insights from 18 months of serial angioscopic follow-up

OBJECTIVES

To clarify the healing process of disrupted culprit plaques of acute myocardial infarction (MI), we serially observed the culprit plaques for 18 months after the onset of acute MI by angioscopy.

BACKGROUND

Although it has been reported that disruption of the yellow plaque and subsequent thrombosis cause acute MI and that the thrombogenicity of the plaque lasts for a month, the healing process of the plaque after disruption has not been clarified.

METHODS

Eighty-five patients with acute MI were prospectively and consecutively enrolled. Angioscopic studies were performed immediately and at 1, 6 and 18 months after successful reperfusion. The prevalence of yellow plaques and thrombus was examined. The color grade of the plaque was determined as 0 (white), 1 (light yellow), 2 (yellow) or 3 (bright yellow).

RESULTS

Although yellow plaque was present at the culprit lesion in most patients throughout follow-up, its color grade was reduced from one to six months (1.9 +/- 0.6 vs. 1.1 +/- 0.7, p = 0.0003) after reperfusion, especially in the patients without hyperlipidemia (HL). The incidence of thrombus was 92.5% immediately after reperfusion, which was reduced significantly to 63.8%, 4.8% and 11.8% at 1, 6 and 18 months, respectively. The incidence of thrombus (77.8% vs. 45.0%, p = 0.03) at one month was higher in the patients with diabetes mellitus (DM).

CONCLUSIONS

The healing process of yellow plaques at the culprit lesions of MI was detected by angioscopy as reductions of color grade and thrombogenicity at six months and partially at one month after the onset of acute MI. This healing process appears to deteriorate by complicating cases of DM or HL.

Medical and socioenvironmental predictors of hospital readmission in patients with congestive heart failure

BACKGROUND

Patients with chronic congestive heart failure (CHF) require frequent rehospitalization because of the exacerbation of CHF. It is of clinical importance to determine predicting factors for readmission to reduce this likelihood. Previous studies have focused primarily on the demographic and medical characteristics in selected subsets of patients. Therefore, within a broad cohort of consecutively hospitalized patients, we sought to identify not only demographic and medical predictors but also socioenvironmental factors associated with readmission.

METHODS

We assessed demographic (age, sex), medical (etiology of CHF, New York Heart Association functional class, left ventricular ejection fraction, previous admission for CHF, length of hospital stay, comorbidity, and medications), and socioenvironmental variables (occupation, financial resources, living alone, and follow-up visits) in 230 patients discharged with a diagnosis of CHF and recorded hospital readmission.

RESULTS

Within 1 year after discharge, 81 patients (35%) were readmitted. Five variables, including poor follow-up visits (odds ratio [OR] 4.9, 95% CI 2.0-11.8), previous admission for CHF (OR 3.3, 95% CI 1.8-6.1), no occupation (OR 2.6, 95% CI 1.2-5.5), longer hospital stay (OR 3.2, 95% CI 1.2-8.5), and hypertension (OR 2.0, 95% CI 1.1-3.7), were identified as significant independent predictors for readmission by multivariate logistic regression analysis.

CONCLUSIONS

Our independent predictors of readmission support the importance of medical and socioenvironmental factors in the deterioration of CHF. Therefore interventions to decrease readmission should also target social management in all hospitalized patients.

Forebrain muscarinic control of micturition reflex in rats

Functional contribution of the cholinergic pathway between the frontal cortex and basal nucleus of Meynert to micturition reflex was investigated. Male Wistar rats were subjected to bilateral lesion of the basal forebrain by ibotenic acid (IA) injection (7.5 microg/rat on each side) (BF rats). Phosphate buffered saline (PBS) was injected into control rats (sham operated rats; SO rats). Cystometrograms were obtained from conscious BF and SO rats 7-10 days after IA/PBS injection. Bladder capacity (BC) of BF rats was significantly smaller than that of SO rats (approximately 43.7%) and was accompanied by decrease in choline-acetyltransferase activity in the frontal cortices. Oxotremorine M, a muscarinic receptor agonist, increased BC in BF rats, while pirenzepine, an M1 muscarinic receptor antagonist, counteracted the effect of the oxotremorine M-induced increase in BC. Injection of oxotremorine M into the dorsal pontine tegmentum (DPT) reduced BC in BF and SO rats, while injection of pirenzepine had no effect on cystometrograms. These findings indicate that the M1 muscarinic receptor plays a part in the forebrain inhibitory mechanisms involved in the micturition reflex and that muscarinic receptor in the DPT contributes to excitatory control of micturition reflex.

Dynamic change in collateral flow associated with myocardial ischemia in humans

BACKGROUND

This study sought to investigate how collateral flow changes during myocardial ischemia in patients.

METHODS

Myocardial contrast echocardiography (MCE) and rapid atrial pacing were performed in 20 patients with angiographically evidenced coronary collaterals from the right coronary artery (RCA) to the occluded left anterior descending coronary artery. Sonicated contrast medium was injected into the RCA before and immediately after atrial pacing to determine the peak background-subtracted contrast intensity (PI) in the collateral territory (PIA) and its ratio to PI in the control territory (PI ratio) as parameters of collateral blood flow. Lactate production in the coronary circulation during pacing was determined to assess myocardial ischemia in the collateral territory.

RESULTS

PIA showed a significant correlation with regional wall motion either before (r(squared)=-0.64, P<0.01) or after pacing (r(squared)=-0.65, P<0.01). Similarly, PI ratio was significantly correlated with regional wall motion either before (r(squared)=-0.54, P<0.05) or after pacing (r(squared)=-0.64, P<0.01). Rapid atrial pacing decreased both PIA and PI ratio significantly greater in patients with lactate production than in those without (PIA: -67+/-53 vs. -15+/-34%, P<0.05; PI ratio: -68+/-49 vs. -8.2+/-32%, P<0.05, respectively), while neither PIA nor PI ratio differ between the two groups of patients before pacing (PIA: 13.8+/-19. vs. 16.2+/-13.3U, P=0.75; PI ratio: 0.70+/-0.71 vs. 0.87+/-0.65, P=0.58, respectively).

CONCLUSIONS

We concluded that (1) collateral flow determined by MCE was closely associated with regional cardiac function, and (2) not the amount of collateral flow at rest, but pacing-induced change of collateral flow seemed to be a determinant of regional ischemia in patients with coronary collaterals.

Expression of neural plasticity related gene in the pontine tegmental area of rats with overactive bladder after cerebral infarction

PURPOSE

We investigated the expression of the neural plasticity related genes c-fos, zif268, c-jun, brain-derived neurotrophic factor and tissue plasminogen activator in the pontine tegmental area in rats with overactive bladder induced by cerebral infarction.

MATERIALS AND METHODS

Cerebral infarction was induced by left middle cerebral artery occlusion in female Sprague-Dawley rats. Bladder activity was monitored by continuous infusion cystometrography in awake rats. Specimens were obtained from the pontine tegmental area 1, 3, 5, 12 and 24 hours after cerebral infarction or sham operation. The effect of 0.1 mg./kg. intravenously of the N-methyl-d-aspartate glutamatergic receptor antagonist MK-801 on bladder activity, and c-fos and zif268 expression after middle cerebral artery occlusion were studied. Real-time reverse transcriptase-polymerase chain reaction was performed with the LightCycler system (Roche Diagnostics, Mannheim, Germany) to evaluate cerebral infarction influences on gene expression in the pontine tegmental area.

RESULTS

Bladder capacity in cerebral infarcted rats was significantly reduced 1 to 24 hours after middle cerebral artery occlusion compared with that of sham operated rats (p <0.05 to 0.01). One hour after occlusion mean c-fos messenger (m)RNA expression plus or minus standard error had significantly increased to 18.9 +/- 4.0 in terms of its density relative to the outer control in a sample obtained immediately after occlusion compared with that in sham operated rats (p <0.05). It returned to the control level within 3 hours after occlusion. Mean zif268 mRNA expression significantly increased to a relative density of 3.2 +/- 1.4 3 hours after middle cerebral artery occlusion (p <0.01) and returned to the control level within 5 hours after occlusion. The expressions of c-jun, brain-derived neurotrophic factor and tissue plasminogen activator was not influenced by occlusion. Pretreatment with MK-801 inhibited bladder overactivity and significantly reduced the expression of c-fos and zif268 mRNA in the pontine tegmental area.

CONCLUSIONS

These results indicate that the development of bladder overactivity after middle cerebral artery occlusion is mediated by activation of an N-methyl-d-aspartate receptor and accompanied by an increase in c-fos and zif268 mRNA expression in the pontine tegmental area.

The morbidity, time course and predictive factors for persistent post-thoracotomy pain

After thoracotomy, patients often suffer from a persistent pain syndrome called post-thoracotomy pain. To elucidate morbidity, time course, and predictive factors for this syndrome, we analyzed follow-up data for 85 post-thoracotomy patients. We used a four-point scale to assess pain: none, slight, moderate and severe. Of 85 patients, 50 reported pain (39 slight, 11 moderate) one day after surgery. A year after surgery, the patients were polled using a simple questionnaire received by the mail. Sixty patients reported persistent pain (34 slight, 14 moderate, 12 severe) a month after surgery, and 35 patients reported persistent pain (33 slight, two moderate) around the time of the poll (1 year after surgery). Although pain deterioration was observed in 40% (34/85) of patients during month 1 after surgery, pain alleviation was seen in 48% (41/85) of patients during months 2-12. Stepwise regression analysis revealed that female gender and pain at postoperative day 1 were predictive for persistent pain both 1 month and 1 year after thoracotomy. Among 35 patients with persistent pain 1 year after surgery, 24 cases reported paresthesia-dysesthesia, and 14 cases reported hypoesthesia. The present data thus suggests that persistent pain is common and often severe 1 month after surgery but is alleviated after 1 year. Clinical time course and symptoms indicate that nerve impairment rather than simple nociceptive impact may be involved in this syndrome.

Interferon gamma-producing ability in blood lymphocytes of patients with lung cancer through activation of the innate immune system by BCG cell wall skeleton

An in vitro assay system was developed to assess the potency of the human innate immune system by measurement of IL-12, IL-18, IL-10 and IFNgamma in the supernatants of bacillus Calmette-Guerin cell wall skeleton (BCG-CWS)-stimulated blood samples. BCG-CWS is a ligand for Toll-like receptor (TLR) 2 and 4, and activates monocytes to macrophages (Mphi), and immature dendritic cells to mature antigen-presenting cells (APC). This system was found to allow the discrimination of immune suppressive states in patients with lung cancer from normal immune states in light of the cytokine profile. The following results were deduced from analyses of BCG-CWS-stimulated blood samples of lung cancer patients with reference to normal subjects. (1) The levels of production of IFNgamma and IL-10 by lymphocytes were decreased. (2) IL-12 p40 production by monocytes/Mphi was upregulated, while that of IL-10 was downregulated. (3) IL-18 was detected in all patients in a range similar to normal subjects. (4) Responses of lymphocytes to IL-2 and IL- 18 in terms of IFNgamma production were diminished. (5) The upregulated IL-12 levels were recovered to within the normal range in most patients after tumor resection. (6) Male patients showed more severe suppression of IL-12/IL-18-mediated IFNgamma production than female patients. Thus, the lesser IFNgamma production observed in patients' blood with high IL-12 p40 levels in response to BCG-CWS may reflect the production of p40 dimers or IL-23 instead of p70, or the presence of some unknown pathways to prohibit the interface between the innate and acquired immune systems. BCG-CWS-mediated Toll signaling may participate in IFNgamma induction for lymphocytes through Mphi/APC IL-12/I-18 modulation.