Single photon emission computerized tomography in childhood hydrocephalus

Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by ¹²³I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome.     

L-dopa facilitates the release of endogenous norepinephrine and dopamine via presynaptic beta 1- and beta 2-adrenoceptors under essentially complete inhibition of L-aromatic amino acid decarboxylase in rat hypothalamic slices

In rat hypothalamic slices, L-aromatic amino acid decarboxylase (AADC) was assayed, and the actions of L-DOPA on impulse (2 Hz)-evoked norepinephrine (NE) and dopamine (DA) release were studied under inhibition of AADC. Slices were incubated with L-DOPA, and DA and NE produced by conversion of the precursor were analyzed by high performance liquid chromatography with electrochemical detection (HPLC-ECD). In the slices, the Km and Vmax of AADC were 131 microM and 122 pmol/min/mg protein, respectively. NSD-1015, an AADC inhibitor, caused a noncompetitive type of inhibition, and the K1 value was 0.086 microM. In the presence of 20 microM NSD-1015, which was expected to cause 99.6% inhibition of AADC, L-DOPA (0.01-100 nM) concentration-dependently facilitated the release of NE from the superfused slices, and the L-DOPA (10 nM)-induced facilitation was antagonized by 100 nM ICI 89,406 and 100 nM ICI 118,551, a selective beta 1- and beta 2-adrenoceptor antagonist, respectively. This action of L-DOPA was not modified by 30 microM tropolone, an inhibitor of catechol-O-methyl-transferase. L-DOPA at 0.01-1 nM similarly facilitated the release of DA. A quantitative analysis revealed that the L-DOPA-induced increase in NE and DA release was much higher by a factor of 3 to 4 orders than was the amount of DA and NE converted from L-DOPA. These results add further support to the hypothesis that L-DOPA itself acts as a neuroactive substance in the rat central nervous system.     

Arterial embolization as preoperative treatment for pulmonary aspergillosis with hemoptysis

Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization, achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery. This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May 13–14, 1994     

The limitation of staged repair in the surgical management of congenital complex heart anomalies with aortic arch obstruction

OBJECTIVE: Severe aortic arch obstruction including an interrupted aortic arch in congenital complex heart anomalies remains a challenge in surgical management. METHODS: Treatment and outcomes in 75 consecutive patients who underwent an aortic arch repair as the first step of the staged repair protocol between 1975 and 2000 were reviewed. Their ages at repair ranged from 1 day to 8.5 months. RESULTS: Cross-sectional postoperative follow-up data were available in all the patients. The follow-up period ranged from 0 to 27.6 years (mean: 7.3 +/- 7.3 years). There were 20 postoperative hospital deaths (27%) and 7 late deaths. The Kaplan-Meier estimate of survival was 81.3% +/- 4.5% at 1 month, 68.0% +/- 5.4% at 1 year, 65.0% +/- 5.5% at 5 years, 63.1% +/- 5.7% at 10 years, 63.1% +/- 5.7% at 20 years. By Cox regression analysis, body weight of 2.5 kg or less is the only independent determinant of postoperative mortality (p = 0.04, multivariable odds ratio: 2.50, [95% confidence interval: 1.02-6.1]). The aortic arch morphology, the primary cardiac lesion, or date of operation did not reach a statistically significant level to show correlation with mortality. Reintervention to reconstruct the aortic arch was performed at 9 occasions in 8 of the 55 patients who survived the primary operation (14.5%). The Kaplan-Meier estimate of the reintervention-free rate was 91.3% +/- 4.2% at 5 years, 85.5% +/- 5.6% at 10 years, 75.6% +/- 8.2% at 20 years. Using multivariable Cox regression analysis, interrupted aortic arch (versus aortic coarctation) was the only independent predictor of a shorter time to reintervention (p = 0.001, multivariable odds ratio: 16.1, [95% confidence interval: 3.2-80.2]). CONCLUSIONS: The staged repair protocol was associated with significant limitations in patient survival and with the development of recurrent aortic arch obstruction. Thus, a primary repair protocol may serve as an alternate approach, especially in patients with low weight or with an interrupted aortic arch.     

A case of emergency surgery for acute mitral regurgitation due to complete papillary muscle rupture as complication of acute inferior myocardial infarction

We experienced a case with acute mitral regurgitation caused by complete posterior papillary muscle rupture as complication of acute inferior myocardial infarction, who underwent successfully emergency operation of mital valve replacement and coronary revascularization in acute stage. A 64-year-old woman developed sudden cardiogenic shock shortly after the onset of acute inferior myocardial infarction. The diagnosis of acute inferior myocardial infarction was based on the electrocardiographic findings. Under IABP support, preoperative coronary angiography visualized total occlusion of segment 3 of the right coronary artery, and preoperative left ventriculography showed akinesis of inferior wall and severe mitral regurgitation. At 6 hours after onset of papillary muscle rupture, emergency operation was performed. At operation, posterior papillary muscle was found to be totally ruptured. Coronary artery revascularization and mitral valve replacement were performed. Postoperative course was uneventful, with 4 days of IABP and 5 days of ventilatory support. She was discharged on the twentieth postoperative day in NYHA class I. Reports of successful emergency operation for total papillary muscle rupture following acute myocardial infarction are rare. Early diagnosis and surgical treatment are mandatory to save this group of patients.     

Potentiation of allergic bronchoconstriction by repeated exposure to formaldehyde in guinea-pigs in vivo

BACKGROUND: Indoor formaldehyde (FA) might worsen allergies and be an underlying factor for the increasing incidence and severity of asthma; the exact mechanism, however, remains unclear. OBJECTIVE: The present study examined the effects of repeated exposure to FA on methacholine- and antigen-induced bronchoconstriction in guinea-pigs in vivo. METHODS: First, non-sensitized guinea-pigs were transnasally treated with 0.1 or 1.0% FA or saline three times a week for 6 weeks, and increasing concentrations of methacholine (50, 100, and 200 microg/mL) were inhaled at 5-min intervals. Second, guinea-pigs pre-treated with transnasal administration of FA or saline using the same protocol were passively sensitized with anti-ovalbumin (OA) serum 7 days before antigen challenge. Third, guinea-pigs were actively sensitized with OA and pre-treated with transnasal administration of FA or saline using the same protocol. The lateral pressure of the tracheal tube (Pao) was measured under anesthesia and artificial ventilation. RESULTS: The antigen-induced increase in Pao in actively sensitized guinea-pigs was significantly potentiated by FA exposure in a dose-dependent manner. The dose-response curve of the methacholine-induced increase in Pao in non-sensitized guinea-pigs or of the antigen-induced increase in Pao in passively sensitized guinea-pigs was not altered by FA exposure. Transnasal administration of FA significantly increased the serum anti-OA homocytotropic antibody titre (IgG) as measured by the passive cutaneous anaphylaxis reaction in actively sensitized guinea-pigs. CONCLUSION: The results suggest that repeated exposure to FA worsens allergic bronchoconstriction through enhancing antigen sensitization.     

Immunocytochemical Evidence of Amyloid-enhancing Factor (AEF) in Polymorphonuclear Leukocytes

Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989.     

An invasion-independent pathway of blood-borne metastasis: a new murine mammary tumor model

It is generally believed that active invasion by cancer cells is essential to the metastatic process. In this report, we describe a murine mammary tumor (MCH66) model of metastasis that does not require invasion into the vascular wall of both the primary tumor and the target organ, in this case, the lung. The process involves intravasation of tumor nests surrounded by sinusoidal blood vessels, followed by intravascular tumor growth in the lung, without penetration of the vascular wall during the process. Comparative studies using a nonmetastatic MCH66 clone (MCH66C8) and another highly invasive metastatic cell line (MCH416) suggested that high angiogenic activity and sinusoidal remodeling of tumor blood vessels were prerequisites for MCH66 metastasis. Differential cDNA analysis identified several genes that were overexpressed by MCH66, including genes for the angiogenesis factor pleiotrophin, and extracellular matrix-associated molecules that may modulate the microenvironment toward neovascularization. Our analyses suggest that tumor angiogenesis plays a role in the induction of invasion-independent metastasis. This model should prove useful in screening and development of new therapeutic agents for cancer metastasis.     

Determination of IgG subclasses of immunoglobulin preparations for intravenous injection and the problems involved

The IgG subclasses of immunoglobulin for intravenous injection (IVIg) were investigated after various different types of treatment. The level of IgG2 was relatively low in preparations treated with pepsin, but by changing the clone producing anti-IgG2 antibody, the level approached that of normal human serum. Though undetectable in sulfonated immunoglobulin preparations, IgG3 was detected after reoxidation. When determining the IgG subclasses of IVIg, it must be kept in mind that the apparent value may subsequently become lower due to the depressed reaction of the antibody.