Survivin inhibits apoptosis in cytotrophoblasts

Survivin, a protein that inhibits apoptosis, is expressed in a variety of tumour cells. We detected survivin-specific mRNA and protein in normal placental tissues, two human choriocarcinoma cell lines (JEG-3 and BeWo), and a trophoblastic cell line (tPA30-1) by reverse transcription-polymerase chain reaction (RT-PCR), Northern blotting, and Western blotting. Immunohistochemically, survivin was localized to normal villous cytotrophoblasts, normal extravillous trophoblasts, cytotrophoblasts in hydatidiform mole, and choriocarcinoma cells. Antisense oligonucleotides for survivin dose-dependently induced apoptosis in two choriocarcinoma cell lines (JEG-3 and BeWo) and a trophoblastic cell line (tPA30-1), while sense oligonucleotides showed little effect. These findings suggest that survivin antagonizes apoptosis in cytotrophoblasts, extravillous trophoblasts, and choriocarcinoma cells.

Comparison of atopic cough with cough variant asthma: is atopic cough a precursor of asthma?

BACKGROUND

We have described a group of patients who present with isolated chronic bronchodilator resistant non-productive cough with an atopic constitution, eosinophilic tracheobronchitis, and airway cough receptor hypersensitivity without bronchial hyperresponsiveness, which we have termed "atopic cough". Although cough variant asthma (in which the cough responds to bronchodilators) is recognised as a precursor of typical asthma, it is not known whether atopic cough is also a precursor of asthma.

METHODS

Eighty two patients with atopic cough were retrospectively examined for onset of typical asthma and compared with 55 patients with cough variant asthma (20 untreated patients and 35 treated with long term inhaled beclomethasone dipropionate (BDP), 218-467 micro g/day). The median follow up period for patients with atopic cough and cough variant asthma was 4.8 (1-11.5) years and 3.7 (1-12.4) years, respectively.

RESULTS

Onset of typical asthma occurred in only one of the patients with atopic cough. In patients with cough variant asthma, typical asthma developed in two of 35 patients taking BDP and six of 20 untreated patients (difference 24.3%, 95% CI 2.8 to 45.8, p<0.02).

CONCLUSIONS

These findings suggest that cough variant asthma is a precursor of typical asthma but that atopic cough is not. Treatment with inhaled steroids may prevent the transformation of cough variant asthma into typical asthma.

Daily bowel movements and Escherichia coli O157 infection

The usual bowel habits of 259 school age children before the large outbreak of E coli O157 infection in Sakai City in the summer of 1996 were investigated. A daily morning movement and/or frequent bowel movements may be a protective factor against infection, while being constipated contributed to a worsening of symptoms.

[Pharmacokinetic and clinical studies on teicoplanin for sepsis by methicillin-cephem resistant Staphylococcus aureus in the pediatric and neonate field]

Pharmacokinetics, clinical efficacy and safety of teicoplanin (TEIC) were evaluated in pediatric and neonate patients with MRSA sepsis in the dosages approved in overseas. The administrated dose for pediatrics patients was 10 mg/kg once at hour 0, 12 and 24, followed by every 24 hours intervals. In neonates patients, first dose was 16 mg/kg, then 8 mg/kg every 24 hours intervals. 1. Pharmacokinetic results. All 17 patients (9 neonates and 8 pediatrics) who received TEIC were evaluated for pharmacokinetics. Trough concentrations were analyzed in 16 patients (9 neonates and 7 pediatrics) excluding one patient for lack of measurement of drug concentration at day 7. No patient with a concentration exceeding 60 micrograms/mL in peak or trough concentrations were reported. Mean concentrations in trough at day 3, 4 and 7 in neonates were 15.2, 14.7 and 17.8 micrograms/mL, and in pediatrics were 12.5, 12.2 and 13.1 micrograms/mL, respectively. These results were similar to those reported in foreign pediatrics and neonates patients. 2. Efficacy and safety results. Since no patient was excluded, all patients were evaluated for efficacy and safety. Microbiological efficacy as well as clinical cure were secondarily evaluated in 2 patients for whom MRSA was isolated from blood. Clinical efficacy rate was 76.5% (13/17) and number of cases in judgments of excellent, good, fairly improved and no change were 12, 1, 3 and 1 cases respectively. The patients for whom MRSA was isolated from blood were judged as MRSA eradicated case and cured without any additional anti-MRSA drugs. Adverse events were reported in 2 neonates and 3 pediatric patients. Possibly related adverse events to study drug (adverse drug reactions) were: 1 case of respiratory disorder, thrombocythemia, gamma-GTP increased, GOT increased and GPT increased in 3 pediatrics. These results suggest that an application of overseas dose regimen of TEIC for neonate and pediatrics is appropriate in Japan.

Leukotriene receptor antagonist, montelukast, can reduce the need for inhaled steroid while maintaining the clinical stability of asthmatic patients

BACKGROUND

Oral leukotriene receptor antagonists have been shown to have efficacy in chronic asthma.

OBJECTIVE

To determine whether the addition of montelukast could lead to a reduction in inhaled corticosteroid dose without a significant decrease in peak expiratory flow rate (PEFR).

METHODS

After a 4-week run-in period, 191 moderate-to-severe asthmatic patients whose asthma had been well controlled with daily inhaled corticosteroid therapy (beclometasone dipropionate 800 to 1600 micro g/day), were randomly assigned to one of two treatments - placebo (n = 98) or montelukast 10 mg once daily (n = 93) - for a 24-week, multicentre, double-blind, treatment period. At the beginning of the active treatment period, the daily dose of inhaled corticosteroid was halved in all of the patients. In addition, the inhaled corticosteroid dose was subsequently titrated every 8 weeks, based on PEFR, asthma symptoms and beta-agonist use.

RESULTS

After 8 weeks of a 50% reduction in inhaled corticosteroid use, morning PEFR increased by 5.3 +/- 32.3 L/min from baseline in patients receiving montelukast and significantly decreased by 6.9 +/- 29.0 L/min in those receiving placebo (P = 0.035). In addition, evening PEFR significantly decreased by 9.8 +/- 28.5 L/min (P = 0.003) in the placebo group, but was maintained in the montelukast group. In spite of a subsequent 50% reduction in the inhaled corticosteroid dose every 8 weeks, morning and evening PEFRs were maintained over the 24-week treatment period in the montelukast group; PEFR significantly decreased in the placebo group. There was a significant difference between the two groups with regard to morning PEFR, therapy score and asthmatic score at weeks 8, 16 and 24, as well as evening PEFR at week 8. However, the symptom scores were not significantly different between the two groups or within each group.

CONCLUSION

These data suggest that montelukast reduces the need for inhaled corticosteroids while maintaining asthma control over a 24-week period. Therefore, montelukast may be useful for long-term treatment in patients with asthma who require high doses of inhaled corticosteroids.

Placental features in preterm infants with periventricular leukomalacia

OBJECTIVE

Evaluation of the placenta provides some important insights into pathophysiologic changes that take place during the prenatal and intrapartum process. We investigated the relationship between placental findings and periventricular leukomalacia (PVL) to obtain a better understanding of its cause.

METHODS

Thirty-two preterm infants with PVL delivered before 34 weeks' gestation, between 1990 and 1999, were classified into 4 groups according to the onset of brain injury assumed from ultrasonographic presentation and clinical course: 2 Antenatal, 22 Peripartum, 5 Postnatal, and 3 in an unknown time of onset group. We evaluated the gross and histopathologic features of the placentas of each group and compared them with those of a control group matched by birth weight and gestational age in terms of the frequency of major placental findings. Potential confounding factors were controlled in logistic regression analyses.

RESULTS

Gross lesions with disturbance of uteroplacental circulation, including massive retroplacental hematoma, extensive infarction or thrombosis, and marked basal or perivillous fibrin deposition, were observed more frequently in the Antenatal + Peripartum combined subgroup than in the controls (41.7% vs 13.7%). Placentas from the Antenatal + Peripartum subgroup also demonstrated a significantly higher frequency of ischemic changes in villi, based on histopathologic examination, as compared with the control group (54.2% vs 13.7%). These associations remained after adjustment for confounding factors in logistic regression analyses (odds ratio: 4.04, 95% confidence interval: 1.40-11.67; and odds ratio: 7.28, 95% confidence interval: 2.50-21.20; respectively). Frequencies of chorioamnionitis and twin placentation tended to be higher in PVL cases than in the controls, although the differences were not statistically significant (46.9% vs 37.9%, 37.5% vs 20.0%, respectively).

CONCLUSIONS

These results suggest that disturbed placental circulation underlies the development of PVL in the majority of cases with prenatal and peripartum brain injury. In chorioamnionitis cases, certain additional factors were suggested in the genesis of PVL. Thus, placental examination is essential for elucidating the pathophysiologic changes leading to PVL in the perinatal process.

Laparoscopic lumbar sympathectomy for lower-limb disease

BACKGROUND

The standard procedure for sympathectomy is open surgery. The oblique retroperitoneal approach is popular because it provides good visibility, albeit at the expense of requiring a long skin incision. Chemical sympathectomy has been introduced as a less invasive means of achieving sympatholysis; however, this method is also associated with a significant incidence of incomplete block and transient denervation. Laparoscopic surgery is a new approach that simplifies various surgical procedures. The aim of our report was to evaluate the benefits of endoscopic retroperitoneal surgery for lumbar sympathectomies.

METHODS

Between March 1997 and April 2000, seven patients underwent laparoscopic lumbar sympathectomy in our department (all men, with an average age or 45.1 years). The predominant presenting symptoms were unilateral pain at rest and lower-extremity coldness. Symphaectomy was performed using a retroperitoneal approach on six patients and an anterior transperitoneal approach on one patient. After laparoscopic lumbar sympathectomy, skin thermometry was carried out on all patients.

RESULTS

The postoperative skin temperature of the affected leg rose to 36.6 +/- 0.5 degrees C, as compared to 33.8 +/- 0.8 degrees C preoperatively. After laparoscopic lumbar sympathectomy, none of the patients complained of neuralgia. All patients achieved sustained symptomatic relief, and no major postoperative complications were noted.

CONCLUSIONS

Lumbar sympathectomy can be performed laparoscopically. Currently, our standard technique is the retroperitoneal approach. More clinical experience and long-term follow-up will ultimately determine if this will become the procedure of choice. However, we believe that a learning period is necessary for this technique to be fully mastered.

Eosinophilic bronchitis: clinical manifestations and implications for treatment

Airway inflammation with eosinophils is now reported to occur not only in asthma but in other airway diseases such as cough variant asthma, chronic cough, atopic cough, episodic symptoms without asthma, allergic rhinitis, and COPD. Although the prevalence of eosinophilic bronchitis (EB) is less than in asthma, the causes, mechanisms and treatment of EB in these conditions appears to be similar to asthma where allergen induced IL-5 secretion and symptoms are readily responsive to inhaled corticosteroids. The prognosis of EB without asthma is not known but it may be a precursor for asthma and, if so, recognition of this syndrome may permit effective treatment and reduction in the rising prevalence of asthma. Induced sputum analysis allows recognition of EB in clinical practice. The place of the asthma treatment paradigm with early and sustained corticosteroid treatment needs to be defined in EB without asthma. Airway wall remodelling can occur in rhinitis, COPD, and cough variant asthma with EB. The mechanisms and long term implications of this complication in EB without asthma need to be clarified.

Endoscopic thyroid resection using cutaneous elevation in lieu of insufflation

BACKGROUND

Laparoscopic surgery to resect cervical masses has gained increasing acceptance during the past decade. This report describes the authors' technique and experience using total video endoscopic surgery to resect thyroid masses.

METHODS

The video camera is introduced through a 12-mm trocar inserted via a 10-mm infraclavicular incision in the sternal line. This incision will be hidden by the patient's undergarments postoperatively. An incision for a 12-mm trocar is made in each axilla, with additional incisions in the anterior chest made as necessary for the endoscope and instruments. Excellent exposure is produced by elevating the skin with hooks rather than by using carbon dioxide insufflation. This method reduces the incidence of subcutaneous emphysema and pneumomediastinum.

RESULTS

Twenty-two thyroid lesions were resected using total video endoscopic surgery (adenoma, 13; cancer, 5; benign cyst, 3; and Graves' disease, 1). Procedures included thyroidectomy (12), thyroidectomy and isthmusectomy (4), and subtotal thyroidectomy (2). Subtotal cervical adenectomy was performed in 3 patients with papillary carcinoma. Cosmetic results were excellent.

CONCLUSION

Endoscopic surgery of the neck is safe, minimally invasive, and produces excellent cosmetic results. However, it is in an early stage of development. Techniques have yet to be standardized, and specialized instruments are not available. The field is likely to mature as surgeons gain more experience.

[A case of tuberous sclerosis with pulmonary lymphangiomyomatosis]

A 52-year-old woman complained of exertional dyspnea. She had two sons with tuberous sclerosis and presented with facial angiofibroma and bilateral renal angiomyolipomas. Her chest radiograph demonstrated diffuse reticular shadows and chest CT revealed numerous well-defined cysts outlined by thin walls. Pulmonary lymphangiomyomatosis was diagnosed by transbronchial biopsy that showed multifocal proliferation of immature smooth muscle cells located in the walls of some bronchi, and in alveolar walls and pulmonary vessels. Immunoreactivity for SMA and HMB 45 was present in the same cells, but immunostaining for estrogen and progesterone receptors was negative. Much is still unknown about pulmonary lymphangiomyomatosis and pulmonary involvement in tuberous sclerosis. Further studies, such as gene analysis, will clarify the relationship between these diseases.

Matrix metalloproteinase inhibition prevents oxidative stress-associated blood-brain barrier disruption after transient focal cerebral ischemia

Oxidative stress generated during stroke is a critical event leading to blood-brain barrier (BBB) disruption with secondary vasogenic edema and hemorrhagic transformation of infarcted brain tissue, restricting the benefit of thrombolytic reperfusion. In this study, the authors demonstrate that ischemia-reperfusion-induced BBB disruption in mice deficient in copper/zinc-superoxide dismutase (SOD1) was reduced by 88% ( P < 0.0001) and 73% ( P < 0.01), respectively, after 3 and 7 hours of reperfusion occurring after 1 hour of ischemia by the inhibition of matrix metalloproteinases. Accordingly, the authors show that local metalloproteinase-generated proteolytic imbalance is more intense in ischemic regions of SOD1 mice than in wild-type litter mates. Moreover, active in situ proteolysis is, for the first time, demonstrated in ischemic leaking capillaries that produce reactive oxygen species. By showing that oxidative stress mediates BBB disruption through metalloproteinase activation in experimental ischemic stroke, this study provides a new target for future therapeutic strategies to prevent BBB disruption and potentially reperfusion-triggered intracerebral hemorrhage.

Effects of suplatast tosilate, a new type of anti-allergic agent, on airway cough hypersensitivity induced by airway allergy in guinea-pigs

BACKGROUND

Cough receptor hypersensitivity is a fundamental feature of some conditions presenting with chronic non-productive cough. Suplatast tosilate, an anti-allergic agent, is a T helper (Th)2 cytokine inhibitor that inhibits the synthesis of interleukin (IL)-4, IL-5, immunoglobulin (Ig)E production, and local eosinophil accumulation.

OBJECTIVE

The purpose of this study was to investigate the effect of suplatast on antigen-induced airway cough hypersensitivity and eosinophil infiltration into the airway.

METHODS

Number of coughs elicited by inhalation of increasing concentrations of capsaicin (10-8, 10-6 and 10-4 M) was counted 24 h after an antigen challenge in conscious guinea-pigs and then bronchoalveolar lavage was performed. We investigated the effect of single (before antigen challenge or capsaicin provocation) or repetitive treatment with intraperitoneal suplatast at a dose of 10 or 30 mg/kg on antigen-induced cough hypersensitivity.

RESULTS

Twenty-four hours after antigen challenge, guinea-pigs developed an increase in cough receptor sensitivity to inhaled capsaicin and eosinophil infiltration in the airways. After a 2-week treatment with suplatast, but not after only a single treatment before antigen challenge or capsaicin provocation, the antigen-induced early phase bronchoconstriction, cough hypersensitivity, and airway eosinophilia were inhibited in a dose-dependent manner.

CONCLUSION

These results indicate that suplatast inhibits airway cough hypersensitivity underlying allergic eosinophilic inflammation.

Macrophage colony-stimulating factor prevents febrile neutropenia induced by chemotherapy

There are very few studies describing the preventive effect of macrophage colony-stimulating factor (M-CSF/CSF-1) on chemotherapy-induced infection. In this study, we evaluated the changes in superoxide anion production by granulocytes before and after chemotherapy in ovarian cancer patients and investigated the preventive effect of M-CSF on chemotherapy-induced febrile neutropenia. Three courses of chemotherapy [paclitaxel 180 mg/m(2) and carboplatin (area under the curve; AUC 5)] were administered to 32 ovarian cancer patients, and seven patients presented febrile neutropenia. In the 25 afebrile patients, the percentage of superoxide anion production by granulocytes was significantly decreased from 86.5 +/- 7.7 (%) to 75.1 +/- 8.8 (%) at day 7 and 71.0 +/- 6.3 (%) at day 14 without administration of CSF. However, in the patients who presented febrile neutropenia, it was more severely decreased from 86.8 +/- 6.8 (%) to 60.0 +/- 9.9 (%) at day 7 and 56.8 +/- 5.0 (%) at day 14 without administration of CSF. When M-CSF was administered to all patients in the next course with the same dose of chemotherapy, the incidence of febrile neutropenia was significantly decreased (P = 0.0195), and the duration of fever (>or= 38.0 degrees C) and high serum C-reactive protein (CRP) (>or= 2.0 mg/dl) were also significantly shortened (P = 0.0023, P = 0.0051). Moreover, in these M-CSF-treated patients, the percentage of superoxide anion production by granulocytes was maintained at the level before chemotherapy. These findings indicate that severe impairment of granulocyte function leads to febrile neutropenia, and that M-CSF reduces the incidence of febrile neutropenia by maintaining or improving granulocyte function.

[Eosinophilic airway diseases presenting with isolated cough except for asthma]

Cough variant asthma (CVA), atopic cough (AC) and eosinophilic bronchitis without asthma (EB) are eosinophilic airway diseases presenting with isolated chronic cough. Among them, bronchodilators are effective only in CVA. Bronchial responsiveness, diurnal variation of pulmonary function and bronchomotor tone are mildly increased to intermediate levels between mild asthma and normal in CVA, but not in AC or EB. Cough sensitivity is heightened in atopic cough and probably in EB, but not in CVA. Bronchoalveolar lavage eosinophilia is present in CVA and EB, but absent in AC. As asthma onset has been recognized in nearly 30% patients with CVA, but not in AC, long-term inhaled corticosteroid therapy is recommended only in CVA.

Superoxide during reperfusion contributes to caspase-8 expression and apoptosis after transient focal stroke

BACKGROUND AND PURPOSE

Reactive oxygen species produced during reperfusion may play a detrimental role in focal cerebral ischemia (FCI). We examined the protein expression of caspase-8, which plays a major role in both Fas-dependent and cytochrome c-dependent apoptotic pathways after FCI with or without reperfusion. Caspase-8 expression after transient FCI was compared between wild-type and transgenic mice that overexpress the cytosolic antioxidant copper/zinc superoxide dismutase (SOD1).

METHODS

Adult male CD-1 mice were subjected to 1 hour of FCI and reperfusion or to permanent FCI by intraluminal blockade of the middle cerebral artery. DNA fragmentation was evaluated by genomic DNA gel electrophoresis. Caspase-8 expression was analyzed by Western blot.

RESULTS

Caspase-8 was significantly induced 4 hours after transient FCI and remained at an increased level until 24 hours, whereas it was not modified after permanent FCI. Genomic DNA gel electrophoresis showed DNA laddering in a pattern similar to that seen in apoptosis, with a small amount of background smear 24 hours after transient FCI, whereas 25 hours of permanent FCI resulted in less DNA laddering with a strong background smear. Caspase-8 induction was significantly reduced in SOD1 transgenic mice compared with wild-type mice 4 hours after transient FCI.

CONCLUSIONS

The results suggest that increased reactive oxygen species production during reperfusion may contribute to the induction of caspase-8, thereby exacerbating apoptosis after FCI.

[A case report of advanced hepatocellular carcinoma successfully treated with surgical multi-ablation therapy based on radio-frequency thermal ablation]

We report a patient with advanced hepatocellular carcinoma (HCC) who was successfully treated with multi-ablation therapy by the surgical method of laparotomy and partial thoracotomy. A 67-year-old man, who had undergone transcatheter arterial embolization (TAE) three times for advanced HCC with hepatitis C, presented at our hospital in May 2001. Although TAE had been performed 3 times starting 2 years earlier, interventional therapy for recurrent tumors is difficult because of stenosis and obstruction of regional hepatic arteries. Computed tomography of the liver revealed five tumors in both lobes and the tumor in segment VIII presented difficulty for percutaneous ablation treatment due to its closeness to the trunk of the hepatic vein. Multi-ablation therapy consisting of radio-frequency ablation, microwave ablation and ethanol injection was selected for this patient. By laparotomy and partial thoracotomy, we performed multi-ablation therapy safely and accurately for each tumor. After this treatment, 5 tumors in both lobes showed no viability on dynamic CT and the patency of the right hepatic vein was preserved. Six months after the treatment, one remnant mass appeared in segment V. An additional two sessions of percutaneous RFA were performed for this tumor. At the end of these treatments, enhanced CT revealed no viability of the tumors, and serum alpha-fetoprotein and PIVKA-II level dropped to the normal range. This case suggests that multiple ablation therapy with a surgical method is feasible and useful in cases of advanced hepatocellular carcinoma.

Effect of thromboxane A2 (TXA2) synthase inhibitor and TXA2 receptor antagonist alone and in combination on antigen-induced bronchoconstriction in guinea pigs

Thromboxane A2 (TXA2) causes bronchoconstriction and bronchial hyperresponsiveness. Two types of TXA2 modifiers, one synthase inhibitor and one receptor antagonist, are widely used for the treatment of asthma in Japan. Although the target of TXA2 modifiers is to inhibit bioactivity of TXA2, the pharmacological properties are somewhat different between these drugs. We studied the inhibitory effects of the TXA2 synthase inhibitor CS-518 and the TXA2 receptor antagonist S-1452 alone and in combination on antigen-induced bronchoconstriction in passively sensitized guinea pigs treated with diphenhydramine. Both CS-518 and S-1452 inhibited the antigen-induced bronchoconstriction dose-dependently with the plateau. The combination of these drugs at the maximal inhibitory doses did not have any more effect compared with each single dosing. The combination at the submaximal doses tended to show an additive effect, but the effect was not significant. These findings suggest that other prostanoids such as PGE2, PGI2, PGD2 and PGF2alpha may not take an important role in the antiasthmatic effects of TXA2 modifiers.

Changes in serotonin levels and 5-HT receptor activity in duodenum of streptozotocin-diabetic rats

Few previous studies have discussed the changes in serotonin receptor activity in the small intestine of diabetic animals. Therefore, we examined serotonin content in duodenal tissue and dose-dependent effects of serotonin agonists and antagonists on the motor activity of ex vivo vascularly perfused duodenum of streptozotocin (STZ)-diabetic rats. Serotonin content was significantly increased in enterochromaffin cells but not altered in serotonin-containing neurons in STZ-diabetic rats. Motor activity assessed by frequency, amplitude, and percent motility index per 10 min of pressure waves was reduced in the duodenum of diabetic rats, and this reduction was reversed by insulin treatment. Serotonin dose dependently increased the motor activity in control rat duodenum but only a higher concentration of serotonin increased the motor activity in diabetic rats. The 5-hydroxytryptamine (5-HT) receptor subtype 4 (5-HT(4)) antagonist SB-204070 dose dependently reduced motor activity in both control and diabetic rats, whereas the 5-HT(3) receptor antagonist azasetron, even at a higher concentration, failed to affect motor activity in diabetic rat duodenum but dose dependently reduced motor activity in control rat duodenum. These results suggest that 5-HT(3) receptor activity was impaired but 5-HT(4) receptor activity was intact in STZ-diabetic rat duodenum. Such an impairment of 5-HT(3) receptor activity may induce the motility disturbance in the small intestine of diabetes mellitus.

Interhemispheric cyst causing leg monoparesis in the elderly--case report

A 64-year-old female presented with a rare case of interhemispheric cerebral cyst manifesting as progressive monoparesis in the right lower extremity for 2 years. Surgical excision of the cyst wall was performed and communication to the subdural space was created. Postoperatively, the cyst was greatly reduced in size, and the neurological signs and symptoms were markedly improved. Interhemispheric cyst often presents with motor disturbances such as hemisparesis or paraparesis. These symptoms tend to progress slowly and sometimes years are required for a proper diagnosis. Interhemispheric cyst can also cause slowly progressive monoparesis in the lower extremity.

Effects of oral steroids on blood CXCR3+ and CCR4+ T cells in patients with bronchial asthma

Corticosteroids are widely used in bronchial asthma, but their mechanism of action is not fully understood. The in vitro studies have proposed that human T helper cells, type 1 (Th1) favor expression of CXCR3, whereas Th2 cells favor CCR4. In this study we investigated whether oral prednisolone modulates the balance of peripheral blood CXCR3+ and CCR4+ T cells. We analyzed the T-cell subsets in 28 patients with stable atopic asthma and 13 normal control subjects before and after 2 wk of treatment with prednisolone, 20 mg/d, or placebo in a randomized, double-blind, parallel group study. The numbers of CXCR3+ and CCR4+ memory T cells were measured with a flow cytometer, and expressed as percentages in CD4+/CD45RO+ memory T cells. In the steroid-treated asthma group, there was a decrease in CCR4+ T cells (from 29.3% to 20.3%, p < 0.0001), and an increase in CXCR3+/ CCR4+ ratio (from 1.86 to 2.89, p = 0.0047), whereas there was no change in CXCR3+ T cells. However, the percentages of CCR4+ cells did not change after steroid therapy in normal control subjects. These results suggest that short-term oral corticosteroid modulates the balances of CXCR3+ and CCR4+ cells in patients with asthma.

In vivo airway eosinophil accumulation induced by polymyxin-B reduces bronchial responsiveness in guinea pigs

BACKGROUND

Chronic desquamative eosinophilic bronchitis and bronchial hyperresponsiveness have been considered essential for bronchial asthma. However, it has not been studied whether airway eosinophils enhance or inhibit bronchial responsiveness in vivo.

OBJECTIVE

This study was conducted to elucidate the influence of airway eosinophil accumulation on bronchial responsiveness in vivo.

MATERIALS AND METHODS

Guinea pigs were transnasally treated with 75 microg/kg of polymyxin-B or vehicle twice a week for a total of 3 weeks. Guinea pigs were surgically cannulated and artificially ventilated 24 h after the last administration of polymyxin-B or vehicle. Ten minutes after the installation of artificial ventilation, ascending doses of methacholine, acetylcholine or histamine were inhaled for 20 s at intervals of 5 min. Subsequent study was conducted 20 min after treatment of 60 mg/kg of indomethacin in the same manner. Final study was conducted in naive guinea pigs after single inhalation of 75 microg/mL of polymyxin B.

RESULTS

The proportion of eosinophils in bronchoalveolar lavage fluid significantly increased in guinea pigs treated with polymyxin-B compared with vehicle. Bronchial responsiveness to inhaled methacholine, acetylcholine and histamine was significantly decreased by the polymyxin-B treatment. This protective effect induced by polymyxin B was abolished by pretreatment of indomethacin. A significant increase in bronchial responsiveness was observed after a single inhalation of polymyxin B.

CONCLUSION

These results suggest that in vivo airway eosinophils may reduce non-specific bronchial responsiveness through inhibitory or bronchoprotective prostanoids.

Oxidative stress-dependent release of mitochondrial cytochrome c after traumatic brain injury

Mitochondrial cytochrome c translocation to the cytosol initiates the mitochondrial-dependent apoptotic pathway. This event has not been previously reported in traumatic brain injury (TBI). The authors determined the expression of cytochrome c in cytosolic and mitochondrial fractions after severe TBI produced by the controlled cortical impact model in the mouse. One hour after trauma there was an increase in cytosolic cytochrome c immunoreactivity. The increases in cytosolic cytochrome c preceded DNA fragmentation, which started at 4 hours. Western blots of mitochondrial and cytosolic fractions confirmed that there was a translocation of cytochrome c from the mitochondria after TBI. Mice deficient in manganese superoxide dismutase (MnSOD) showed an increased loss of mitochondrial cytochrome c after trauma, but less apoptotic cell death 4 and 24 hours after injury compared with wild-type control mice. However, the overall cell death was increased in MnSOD mice, as illustrated by a larger cortical lesion in these animals. The results show that cytochrome c is released from the mitochondria after severe TBI partly by a free radical-dependent mechanism, and that massive mitochondrial cytochrome c release is a predictor of necrotic cell death rather than apoptosis.