Surgical management of multiple coronary artery to coronary sinus fistulas with giant left circumflex artery and multivalvular infective endocarditis

Coronary artery fistula (CAF) is characterized as a congenital or acquired abnormal communication between a coronary artery and any of the four chambers of the heart (coronary-cameral fistula) or great vessels (coronary arteriovenous fistula) bypassing the capillaries within myocardium. CAF is a rare disease, challenging to diagnose and treat depending on the anatomical location and type of the fistula and accompanying diseases. This study aims to report a case with multiple coronary artery to coronary sinus (CS) fistulas with giant left circumflex artery and multivalvular infective endocarditis.

Safety and efficacy of pelvic arterial embolization for primary postpartum hemorrhage in hemodynamically stable and hemodynamically unstable patients: Is it "time" for a paradigm change?

BACKGROUND

Pelvic artery embolization (PAE) is an effective and safe technique for treating postpartum hemorrhage (PPH) with hemodynamic stability. However, its use in hemodynamically unstable patients remains controversial.

PURPOSE

To determine the safety and efficacy of pelvic arterial embolization (PAE) according to the hemodynamic state of primary postpartum hemorrhage (PPH) patients.

METHODS

This cohort study was conducted retrospectively, using data from January 2004 to December 2021, in a resource-rich setting at a tertiary Level 1 trauma academic center. A total of 437 patients were diagnosed with PPH during the study period. Of these 437 patients, 161 with primary PPH who underwent PAE were enrolled in the study. The outcomes assessed included the clinical success rate, mortality, the overall success rate, predictive factors for failed PAE, and time-dependent changes in hemodynamic parameters, such as systolic blood pressure (SBP), heart rate (HR), and shock index (SI). Propensity score (PS) matching analysis was performed to assess the influence of specific variables or conditions on the outcomes.

RESULTS

Of the 161 patients who underwent PAE for primary PPH (mean age, 32.9 ± 4.3 [SD]), 85 were retrospectively categorized as having hemodynamic stability (mean age, 32.6 ± 4.1 [SD]), while 76 were categorized as having hemodynamic instability (mean age, 33.3 ± 4.4 [SD]). This study showed PAE for primary PPH had a success rate of 91.9 %, with no significant difference in mortality rates between the groups. The clinical success rate was 98.8 % for patients with hemodynamic stability and 84.2 % for those with hemodynamic instability (p < .001). The overall success rate was 98.8 % for hemodynamic stability and 89.5 % for hemodynamic instability (p = .014). After propensity score matching, the clinical success rate was higher in hemodynamically stable patients than in unstable ones (100 % vs. 86.3 %, p = .013). However, there was no significant difference in the overall success rate (100 % vs. 90.2 %, p = .056). Among the PS-matched population, predictive factors for the failed PAE in primary PPH were hemodynamic instability (adjusted odds ratio [aOR] 21.22, 95 % CI 1.27-355.76; p = .034) and emergency Cesarean delivery with accompanying hemorrhag (aOR 54.00, 95 % CI 11.93-244.56; p = .008). In three groups within a PS-matched population - hemodynamically stable, unstable with successful outcomes, and unstable with unsuccessful outcomes, a generalized linear mixed model (GLMM) analysis for time-dependent changes in hemodynamic parameters revealed a statistically significant difference in SBP, HR, and SI at various time points.

CONCLUSION

Pelvic arterial embolization of primary postpartum bleeding in hemodynamic instability has been identified as an alternative, safe, and effective life-saving procedure for multidisciplinary treatment in resource-rich environments even after the baseline characteristics are balanced by the PS matching, suggesting it is a primary care option.

Regulating POLR3G by MicroRNA-26a-5p as a promising therapeutic target of lung cancer stemness and chemosensitivity

Cancer stem cells (CSCs) identified in lung cancer exhibit resistance to chemotherapy, radiotherapy, and targeted therapy. Therefore, a technology for controlling CSCs is needed to overcome such resistance to cancer therapy. Various evidences about the association between epithelial-mesenchymal transition related transcriptomic alteration and acquisition of CSC phenotype have been proposed recently. Down-regulated miR-26a-5p is closely related to mesenchymal-like lung cancer cell lines. These findings suggest that miR-26a-5p might be involved in lung cancer stemness. RNA polymerase III subunit G (POLR3G) was selected as a candidate target of miR-26a-5p related to cancer stemness. It was found that miR-26a-5p directly regulates the expression of POLR3G.Overexpression of miR-26a-5p induced a marked reduction of colony formation and sphere formation. Co-treatment of miR-26a-5p and paclitaxel decreased cell growth, suggesting that miR-26a-5p might play a role as a chemotherapy sensitizer. In the cancer genome atlas data, high miR-26a-5p and low POLR3G expression were also related to higher survival rate of patients with lung adenocarcinoma. These results suggest that miR-26a-5p can suppress lung cancer stemness and make cancer cell become sensitive to chemotherapy. This finding provides a novel insight into a potential lung cancer treatment by regulating stemness.

Abstract 817: microRNA-26a-5p is a prognostic factor that regulates cancer stemness

Background: Cancer stem cells (CSCs) identified in lung cancer exhibit resistance to chemotherapy, radiotherapy, and targeted therapy. Therefore, a technology to control of CSCs is needed to overcome such resistance to cancer therapy. Various evidences about the association between epithelial-mesenchymal transition related transcriptomic alteration and acquisition of CSC phenotype have been proposed recently. In our previous research, down-regulated miR-26a-5p is closely related to mesenchymal-like lung cancer cell lines. These findings suggest that miR-26a-5p might be involved in lung cancer stemness.

Methods: RNA polymerase III subunit G (POLR3G) was selected as a candidate target of miR-26a-5p related to cancer stemness. its quantitative relationship was investigated by polymerase chain reaction, western blot after transfection of miR-26a-5p. luciferase assay were done for investigating the direct regulation of miR-26a-5p on POLR3G expression. After transfection of miR-26a-5p, colony formation assay and sphere formation assay were performed to evaluate the effect on cancer stemness. By treating cancer cell by miR-26a-5p and paclitaxel, cell viability was checked by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and Muse cell analyzer. Expression level of each gene and its impact on survival were revealed by the cancer genome atlas pancancer database.

Results: miR-26a-5p regulated the expression of POLR3G directly. Overexpression of miR-26a-5p induced down regulation of POLR3G and a marked reduction of colony formation and sphere formation. Co-treatment of miR-26a-5p with paclitaxel decreased cell growth, suggesting that miR-26a-5p might play a role as a chemotherapy sensitizer. In the cancer genome atlas data, down-regulated miR-26a-5p and up-regulated POLR3G were shown compared to adjacent normal tissue. High miR-26a-5p and low POLR3G expression were also related to higher survival rate of patients with lung adenocarcinoma.

Conclusions: Overexpression of miR-26a-5p can suppress lung cancer stemness and make cancer cell become sensitive to chemotherapy. This finding provides a novel insight into a potential lung cancer treatment by regulating stemness.

Citation Format: Daeun Kang, Chang Ryul Park, Minhyeok Lee, Su Yel Lee, Se Jin Park, Wan Jin Hwang, Gwan Woo Ku, Seong Lan Yu, In Beom Jeong, Sun Jung Kwon, Jaeku Kang, Eung Bae Lee, Ji Woong Son. microRNA-26a-5p is a prognostic factor that regulates cancer stemness [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 817.

Quadriplegia after Mitral Valve Replacement in an Infective Endocarditis Patient with Cervical Spine Spondylitis

The simultaneous incidence of infective endocarditis and cervical spondylitis with an epidural abscess is rare, and quadriplegia as a complication after cardiac surgery is very rare. We recently observed quadriplegia after mitral valve replacement in an infective endocarditis patient with cervical spine spondylitis. With early symptom detection, immediate examination, and prompt surgical treatment, the patient successfully recovered without neurological symptoms.

Prognostic Utility of Disproportionately Enlarged Subarachnoid Space Hydrocephalus in Idiopathic Normal Pressure Hydrocephalus Treated with Ventriculoperitoneal Shunt Surgery: A Systematic Review and Meta-analysis

BACKGROUND

Disproportionately enlarged subarachnoid space hydrocephalus is a specific radiologic marker for idiopathic normal pressure hydrocephalus. However, controversy exists regarding the prognostic utility of disproportionately enlarged subarachnoid space hydrocephalus.

PURPOSE

Our aim was to evaluate the prevalence of disproportionately enlarged subarachnoid space hydrocephalus in idiopathic normal pressure hydrocephalus and its predictive utility regarding prognosis in patients treated with ventriculoperitoneal shunt surgery.

DATA SOURCES

We used MEDLINE and EMBASE databases.

STUDY SELECTION

We searched for studies that reported the prevalence or the diagnostic performance of disproportionately enlarged subarachnoid space hydrocephalus in predicting treatment response.

DATA ANALYSIS

The pooled prevalence of disproportionately enlarged subarachnoid space hydrocephalus was obtained. Pooled sensitivity, specificity, and area under the curve of disproportionately enlarged subarachnoid space hydrocephalus to predict treatment response were obtained. Subgroup and sensitivity analyses were performed to explain heterogeneity among the studies.

DATA SYNTHESIS

Ten articles with 812 patients were included. The pooled prevalence of disproportionately enlarged subarachnoid space hydrocephalus in idiopathic normal pressure hydrocephalus was 44% (95% CI, 34%-54%). The pooled prevalence of disproportionately enlarged subarachnoid space hydrocephalus was higher in the studies using the second edition of the Japanese Guidelines for Management of Idiopathic Normal Pressure Hydrocephalus compared with the studies using the international guidelines without statistical significance (52% versus 43%, P = .38). The pooled sensitivity and specificity of disproportionately enlarged subarachnoid space hydrocephalus for prediction of treatment response were 59% (95% CI, 38%-77%) and 66% (95% CI, 57%-74%), respectively, with an area under the curve of 0.67 (95% CI, 0.63-0.71).

LIMITATIONS

The lack of an established method for assessing disproportionately enlarged subarachnoid space hydrocephalus using brain MR imaging served as an important cause of the heterogeneity.

CONCLUSIONS

Our meta-analysis demonstrated a relatively low prevalence of disproportionately enlarged subarachnoid space hydrocephalus in idiopathic normal pressure hydrocephalus and a poor diagnostic performance for treatment response.

MicroRNA-7-5p's role in the O-GlcNAcylation and cancer metabolism

O-GlcNAc Transferase (OGT) is a complementary enzyme that regulates O-linked N-acetylglucosaminylation(O-GlcNAcylation) and plays a critical role in various cancer phenotypes, including invasion, migration, and metabolic reprogramming. In our previous study we found that miR-7-5p was downregulated at lung cancer cells with highly metastatic capacity. In the in-silico approach, OGT is the predicted target of miR-7-5p. To identify miR-7-5p′s role in cell growth and metabolism, we transfected various lung cancer cell lines with miR-7-5p. The expression level of miR-7-5p was confirmed by qRT-PCR in lung cancer cell lines. Western blot assays and qRT-PCR were performed to demonstrate miR-7-5p′s effect. Bioinformatic analysis indicated that OGT is a direct target of miR-7-5p. The binding sites of miR-7-5p in the OGT 3′ UTR were verified by luciferase reporter assay. To investigate the role of miR-7-5p in the cancer metabolism of non-small cell lung cancer (NSCLC) cells, mimic of miR-7-5p was transfected into NSCLC cells, and the effect of miR-7-5p on cancer metabolism was analyzed by LDH assays, glucose uptake, and mitochondrial ATP synthase inhibitor assay. O-GlcNAcylated protein level was determined by Western blot. The role of miR-7-5p in lung cancer growth was measured by MTS assays. To identify the delivery of miR-7-5p via PLGA, an in vitro release assay of PLGA-miR-7-5p was done. miR-7-5p was highly expressed whereas OGT showed low expression in H358, H827. However, miR-7-5p exhibited low expression while OGT had high expression in H522, H460, and H1299 cell lines. OGT were repressed by binding of miR-7a-5p to the 3′-UTR. Overexpression of miR-7-5p also diminished anaerobic glycolysis. miR-181a-5p transfection induced expression levels of OGT were diminished compared to those in the control group. O-GlcNAcylation was suppressed by miR-7-5p. Moreover, the overexpression of miR-7-5a suppressed lung cancer cell growth. miR-7-5p was released via PLGA for up to 10 days. In the present study, inhibition of OGT by miR-7-5p decreased the growth and cancer metabolism of lung cancer.

Acute Type A Aortic Dissection in a Patient with Situs Inversus Totalis

We describe the occurrence of acute type A aortic dissection in a patient with situs inversus totalis. A 37-year-old man presented to the emergency department with acute chest pain. Initial chest X-ray findings showed a right-sided heart and a left-sided liver. Contrast- enhanced computed tomography revealed a Stanford type A acute aortic dissection, aortic root dilatation, and situs inversus totalis. All of the thoracic structures were mirror-image reversed and an abnormal coronary artery was observed. The Bentall operation was performed. This report demonstrates that computed tomography and echocardiography were useful for understanding the anatomy and the presence or absence of concurrent anomalies in a patient with situs inversus totalis. The patient's postoperative course was uneventful.

A 31-year-old pericardial textiloma

Gossypibomas are uncommon but important complications of surgery. This case report is of a gossypiboma found accidentally 31 years after heart surgery. A 41-year-old man had lost 5 kg in the previous three months and suffered from intermittent epigastric discomfort. A computed tomography scan incidentally revealed a well-defined mass in the right lower anterior mediastinum. Given his history of previous cardiac surgery to repair a ventricular septal defect, the possibility of gossypiboma could not be excluded. Elective excision of the mass was performed through a median sternotomy, and a 5-cm ovoid mass consisting of a thrombus and gauze was removed. The postoperative course was uneventful. The patient's clinical findings were normal, with no abnormal findings on transthoracic echocardiogram performed one year later.

PCDHGA12 methylation biomarker in bronchial washing specimens as an adjunctive diagnostic tool to bronchoscopy in lung cancer

The use of bronchoscopy is central to the diagnosis of lung cancer. However, the sensitivity of bronchoscopy is low. In addition, bronchial washing cytology, which is a routine adjunctive test, does not significantly improve the performance of bronchoscopy owing to its low sensitivity. To enhance the diagnostic performance of bronchoscopy, the protocadherin GA12 (PCDHGA12) methylation biomarker in bronchial washings was introduced as a novel adjunctive diagnostic test. A total of 98 patients who underwent bronchoscopy owing to suspicion of lung cancer were analyzed. Cytological examination and PCDHGA12 methylation biomarker testing of the bronchial washing fluid were performed. The performance of the tests was analyzed. The final diagnosis in 60 patients was lung cancer and in 38 patients was benign disease. The PCDHGA12 methylation biomarker had a sensitivity of 75.0%, a specificity of 78.9% and a positive predictive value (PPV) of 84.9%, whereas cytological assessment had a sensitivity of 45.0%, a specificity of 92.1% and a PPV of 90%. Patients with positive PCDHGA12 methylation test had an odds ratio for lung cancer of 11.25 (confidence interval, 4.25-29.8) compared with negative subjects. The combination of the two tests exhibited an increased sensitivity (83.3%), a specificity of 71.1% and a PPV of 82.0%. Furthermore, considering the non-diagnostic bronchoscopy group alone, the test demonstrated a sensitivity of 61.9% and a specificity of 78.9%. The results of the present study demonstrated that PCDHGA12 methylation, as a lung cancer biomarker in bronchial washings, may be a used as an adjunctive test to bronchoscopy.

Foregut duplication cyst: a novel computed tomography finding mimicking a small bowel hernia: A case report

RATIONALE

A foregut duplication cyst (FDC) is an uncommon congenital disease. This report presents a case of mediastinal foregut duplication cyst that mimicked a diaphragmatic small bowel hernia.

PATIENT CONCERN

A 27-month-old girl was first referred for a mediastinal lesion found incidentally on a chest radiograph. At that time, our impression was cystic lung lesion such as congenital pulmonary airway malformation or pulmonary sequestration. At the age 6 years, she presented with recurrent vomiting. The physical examination and laboratory studies were within normal limits.

DIAGNOSES

Chest CT revealed a thin- and smooth-walled cystic mass containing an air-fluid level in the left paravertebral space. It had several inner circular folds and characteristic double-layer enhancement and inner circular fold. Our radiological impression was a type I congenital cystic adenomatoid malformation.

INTERVENTIONS

The patients undergone video-assisted thoracoscopic surgery for excision. The operative finding was the cystic mass with smooth bowel-like outer surface and located between the aorta and heart. The cyst was excised and confirmed to be a foregut duplication cyst pathologically.

OUTCOMES

The patient was doing well with no postoperative complications during follow-up. Recurrent vomiting was improved. This is the first case report describing foregut duplication cyst mimicking a small bowel hernia.

LESSONS

Foregut duplication cysts are rare congenital anomalies of primitive foregut origin. They can occur at any level of the alimentary track and comprise approximately 10% of all mediastinal tumors. Its characteristic double-layered histopathological nature, an FDC can show a double-layered enhancement pattern, which is typical in the alimentary tract.

Extracorporeal Cardiopulmonary Resuscitation with Therapeutic Hypothermia for Prolonged Refractory In-hospital Cardiac Arrest

BACKGROUND AND OBJECTIVES

We identified the impact of extracorporeal cardiopulmonary resuscitation (ECPR) followed by therapeutic hypothermia on survival and neurologic outcome in patients with prolonged refractory in-hospital cardiac arrest (IHCA).

METHODS

We enrolled 16 adult patients who underwent ECPR followed by therapeutic hypothermia between July 2011 and December 2015, for IHCA. Survival at discharge and cerebral performance category (CPC) scale were evaluated.

RESULTS

All patients received bystander cardiopulmonary resuscitation (CPR); the mean CPR time was 66.5±29.9 minutes, and the minimum value was 39 minutes. Eight patients (50%) were discharged alive with favorable neurologic outcomes (CPC 1-2). The mean follow-up duration was 20.1±24.3 months, and most deaths occurred within 21 days after ECPR; thereafter, no deaths occurred within one year after the procedure.

CONCLUSION

ECPR followed by therapeutic hypothermia could be considered in prolonged refractory IHCA if bystander-initiated conventional CPR is performed.

Outcome of Limited Video-Assisted Lumbar Sympathetic Block for Plantar Hyperhidrosis Using Clipping Method

BACKGROUND

There are many ways to treat focal hyperhidrosis, including surgeries for palmar and axillary hyperhidrosis. However, doctors and patients tend to be reluctant to perform surgery for plantar hyperhidrosis due to misconceptions and prejudices about surgical treatment. In addition, few studies have reported the outcome of surgeries for plantar hyperhidrosis. Therefore, the objective of this study was to determine the outcome (early and late postoperative satisfaction, complication, compensatory hyperhidrosis, recurrence rate, and efficiency) of surgical treatment for plantar hyperhidrosis.

MATERIALS AND METHODS

From August 2014 to October 2015, lumbar sympathetic block (LSB) was performed in 82 patients with plantar hyperhidrosis using clipping method. Limited video-assisted LSB was performed using 5 mm ligamax-clip or 3 mm horizontal-clip after identifying L3-4 sympathetic ganglion through finger-touch and endoscopic vision.

RESULTS

Of the 82 patients, 45 were male and 37 were female. Their mean age was 26.38 years (range, 14-51 years). Mean follow-up time was 6.60 ± 3.56 months. Mean early postoperative satisfaction score was 9.6 on the 10th day postoperative evaluation. At more than 1 month later, the mean late postoperative satisfaction score was 9.2. There was no significant difference in early postoperative satisfaction score between clipping level L3 and L4/5. However, late postoperative satisfaction score was significantly better in the L3 group than that in the L4/5 group. Patient's age and body mass index did not affect the satisfaction score. However, male patients and patients who had history of hyperhidrosis operation showed higher satisfaction score than others.

CONCLUSION

Limited video-assisted LSB using clip provided good results with minimal complications and low compensatory hidrosis, contrary to the prejudice toward it. Therefore, surgical treatment is recommended for plantar hyperhidrosis.

Chemical Pleurodesis Using Mistletoe Extraction (ABNOVAviscum(®) Injection) for Malignant Pleural Effusion

PURPOSE

Malignant pleural effusion (MPE) is common in patients with advanced cancer. Chemical pleurodesis can be considered for MPE that do not respond to chemotherapy, radiotherapy, or therapeutic thoracentesis. However, it is not yet clear which agent is more effective and safer in chemical pleurodesis.

METHODS

This study was designed as a single arm, multicenter, and open-label phase III clinical trial to evaluate efficacy and safety of chemical pleurodesis using mistletoe extraction (ABNOVAviscum(®) Injection). References of other agents in chemical pleurodesis were investigated to compare efficacy and safety. Efficacy was evaluated by followed up chest X-ray and changes of clinical symptoms and Karnofsky performance scale. Safety was evaluated by serious adverse event (SAE) and changes of laboratory findings. A follow-up period was 4 weeks after last pleurodesis.

RESULTS

Of 62 patients, 49 (79.0%) had complete response, 11 (17.7%) had partial response, and two had no response. Mean response rate was significantly different in this study comparing with reference response rate which was 64% (p <0.0001). There were two SAEs, but all were recovered without sequelas.

CONCLUSION

The results of this study suggest that mistletoe extraction (ABNOVAviscum(®) Injection) could be an effective and safe agent of chemical pleurodesis in patients with MPE.

Case of bronchoesophageal fistula with gastric perforation due to multidrug-resistant tuberculosis

Gastric perforation and tuberculous bronchoesophageal fistula (TBEF) are very rare complications of extrapulmonary tuberculosis (TB). We present a case of pulmonary TB with TBEF and gastric perforation caused by a multidrug-resistant tuberculosis strain in a non-acquired immune deficiency syndrome male patient. The patient underwent total gastrectomy with Roux-en-Y end-to-side esophagojejunostomy and feeding jejunostomy during intravenous treatment with anti-TB medication, and esophageal reconstruction with colonic interposition and jejunocolostomy were performed successfully after a full course of anti-TB medication. Though recent therapies for TBEF have favored medication, patients with severe stenosis or perforation require surgery and medication with anti-TB drugs based upon adequate culture and drug susceptibility testing.

Extraskeletal osteosarcoma arising from the pleura

A 37-year-old woman was referred to our institution for further management of a mass lesion located in the thoracic cavity. The mass had grown by more than 10 cm over the course of a year and was initially considered to be a scar from previous pulmonary tuberculosis at another hospital. The patient had complained of left-sided flank pain for a year and experienced dyspnea for one month. Chest radiography and chest computed tomography revealed an irregular-shaped mass in the left mid to lower pleural cavity. The mass was widely excised through left thoracotomy. Pathologic examination of the biopsy specimen revealed a malignant spindle cell tumor, which consisted of components of osteosarcoma, pleomorphic sarcoma, and leiomyosarcoma. The patient underwent adjuvant chemotherapy and has been doing well without any evidence of recurrence for 14 months.

Non-infected and Infected Bronchogenic Cyst: The Correlation of Image Findings with Cyst Content

We hereby report a case on bronchogenic cyst which is initially non-infected, then becomes infected after bronchoscopic ultrasound (US)-guided transesophageal fine-needle aspiration (FNA). The non-infected bronchogenic cyst appears to be filled with relatively echogenic materials on US, and the aspirate is a whitish jelly-like fluid. Upon contrast-enhanced MRI of the infected bronchogenic cyst, a T1-weighted image shows low signal intensity and a T2-weighted image shows high signal intensity, with no enhancements of the cyst contents, but enhancements of the thickened cystic wall. The patient then undergo video-assisted thoracic surgery 14 days after the FNA. The cystic mass is known to be completely removed, and the aspirate is yellowish and purulent. To understand the image findings that pertain to the gross appearance of the cyst contents will help to diagnose bronchogenic cysts in the future.

Prospective phase II trial of a combination of gemcitabine and UFT as first-line treatment in elderly patients with advanced non-small cell lung cancer

BACKGROUND

The standard regimen in elderly patients with non-small-cell lung cancer (NSCLC) is still uncertain. Gemcitabine is one of the most widely used drugs for the treatment of NSCLC, and several phase II trials specifically designed for elderly patients with advanced NSCLC have confirmed the role of gemcitabine in this setting. In addition, oral uracil-tegafur (UFT) was associated with a survival advantage in the adjuvant setting. Therefore, we performed a phase II study using the combination of gemcitabine and UFT as first-line therapy in elderly patients with advanced NSCLC.

METHODS

Chemotherapy-naïve, elderly (≥ 70 years) patients who had histologically or cytologically confirmed with stage IIIB or IV NSCLC with a performance status of 1-2 were enrolled. Patients received gemcitabine (1250 mg/m(2) on days 1 and 8, respectively) and UFT (400mg/day on days 1-14) every 3 weeks for up to four cycles. Patients who had not progressed after four cycles continued UFT monotherapy until progression. Primary endpoint was overall response rate and secondary endpoints were overall survival, time to progression and safety profiles.

RESULTS

Between March 2008 and November 2010, 48 patients were enrolled. The median age was 74.5 years (range: 70-84 years), and there were 29 males. The performance status was 1 in 41 and 2 in 7 patients. Thirty-one (64.6%) patients were stage IV and seventeen (35.4%) patients were stage IIIB. Thirty patients (62.5%) completed four cycles of chemotherapy. Response was evaluated in 44 patients. Partial response was achieved in twelve (25.0%) patients and stable disease in 23 (47.9%) patients. Disease control rate was 72.9%. The median survival time was 6.1 months (95% confidence interval [CI]; 5.1-7.0 months), the 1-year survival rate was 29.1% and the median time to progression was 4.6 months (95% CI; 3.7-5.5 months). Toxicities were mild and mostly hematological adverse events. Grade 3/4 neutropenia occurred in 8.3% of patients and one patients experienced febrile neutropenia. Grade 3/4 anemia and thrombocytopenia occurred in 2.1% and 2.1% of patients, respectively. Non-hematological toxicities were tolerable.

CONCLUSIONS

The combination of gemcitabine and UFT was effective in disease control and well tolerated first-line regimen in elderly patients with advanced NSCLC.

Experience without using venoveno bypass in adult orthotopic liver transplantation

BACKGROUND

Venoveno bypass (VVB) has been used to achieve hemodynamic stability and decrease the incidence of renal dysfunction. However, VVB has many complications. The purpose of this study is to verify the safety of total clamping of the suprahepatic inferior vena cava (IVC) without VVB during orthotropic liver transplantation (OLT) in terms of anesthetic management.

METHODS

Twenty-five patients without preoperative renal dysfunction who underwent primary OLT were enrolled in this study. Hemodynamic data and blood gas measurements were collected 1 hour after incision, 30 minutes after IVC total clamping and 30 minutes after reperfusion. Postoperative laboratory data, including blood urea nitrogen (BUN), creatinine (Cr) and glomerular filtration rate (GFR), were assessed at postoperative day (POD) 0-7, 30, 90, 180 and 1 year.

RESULTS

Mean blood pressure was well maintained during IVC total clamping with infusion of inotropics. There was no case of severe acidosis (pH < 7.2) during the anhepatic period. The immediate postoperative Cr and GFR were not significantly different from those of the preoperative values. BUN increased from POD 1 and decreased after POD 6, while Cr increased at POD 90 only.

CONCLUSIONS

In patients without preoperative renal dysfunction, when IVC was totally clamped, VVB does not need to be routinely performed to maintain hemodynamics during the anhepatic phase and renal function after OLT.

Acute Myocardial Infarction Due to Unruptured Aneurysm of Left Sinus of Valsalva with Aortic Valve Regurgitation

This report describes a 35-year-old woman with unruptured aneurysm of the left sinus of Valsalva presenting as non-ST elevation myocardial infarction due to the compression of the left coronary artery by aneurysm. Cardiac multislice CT and angiogram revealed a large aneurysm of the left sinus of Valsalva compressing the left main coronary artery. Surgical repair was performed by closing the entrance of the aneurysm and aortic valve replacement. Postoperative coronary flow was restored and thus anginal symptom disappeared.

A less intensive combination of paclitaxel and carboplatin in advanced non-small cell lung cancer patients who have aged 60 years or more and has a poor performance status

BACKGROUND

The aim of this study was to evaluate the response, survival, and toxicities of a less intensive combination of paclitaxel and carboplatin, which is used in advanced non-small cell lung cancer (NSCLC) patients older than 60 years of age including those with a poor performance status.

METHODS

Thirty patients received 135 mg/m2 of paclitaxel on day 1, and carboplatin was administered to the patients on day 1 every 4 weeks over an area under the concentration-time curve of 6.

RESULTS

The response rate was 40%, the median overall survival was 9.1 months (95% CI, 4.2 to 14 months), and the 1 year survival rate was 31%. The median progression-free survival was 7.7 months (95% CI, 3.1 to 12.2 months). In addition, the toxicities were generally mild and reversible.

CONCLUSION

This study demonstrates that a less intensive combination of paclitaxel/carboplatin is active and well tolerated in advanced NSCLC patients who are older than 60 years including those with a poor PS 3-4.

Preparation and solubility in acid and water of partially deacetylated chitins

Partially deacetylated chitins with different degrees of deacetylation (DD) were prepared by alkaline treatment under homogeneous conditions, and the effect of DD on their solubility was discussed in terms of crystal structure and mode of hydrogen bonding. With an increase in the treatment time, the DD of chitin increased proportionally. The chitin became soluble in dilute acetic acid at the DD of ca. 28% or over and soluble in water at the DD of ca. 49%. The solubility of the partially deacetylated chitins had a close relationship with their crystal structure, crystallinity, and crystal imperfection as well as the glucosamine content. The wide-angle X-ray diffractometry (WAXD) revealed that the chitin with ca. 28% DD retained the crystal structure of alpha-chitin with significantly reduced crystallinity and perfection of the crystallites. The water-soluble chitin of ca. 49% DD had a new crystal structure similar to that of beta-chitin rather than either alpha-chitin or chitosan, suggesting that the homogeneous deacetylation transformed the crystal structure of chitin from the alpha to the beta form. Some hydrogen bonds existing in raw alpha-chitin were found to be missing at a DD of ca. 49%.

Chronic psychosocial stress impairs learning and memory and increases sensitivity to yohimbine in adult rats

BACKGROUND

It is well known that intense and prolonged stress can produce cognitive impairments and hippocampal damage and increase noradrenergic activity in humans. This study investigated the hypothesis that chronic psychosocial stress would affect behavior, drug sensitivity, and hippocampal-dependent learning and memory in rats. The work provides a novel connection between animal and human studies by evaluating the effects of stress on a rat's response to yohimbine, an alpha(2) adrenergic receptor antagonist.

METHODS

Rats were exposed to a cat for 5 weeks and randomly housed with a different group of cohorts each day (psychosocial stress). The effects of the stress manipulations were then assessed on open field behavior, spatial learning and memory in the radial arm water maze and the behavioral response to a low dose of yohimbine (1.5 mg/kg).

RESULTS

Stressed rats displayed impaired habituation to a novel environment, heightened anxiety, and increased sensitivity to yohimbine. In addition, the stressed rats exhibited impaired learning and memory.

CONCLUSIONS

There are commonalities between the current findings on stressed rats and from studies on traumatized people. Thus, psychosocial stress manipulations in rats may yield insight into the basis of cognitive and neuroendocrine disturbances that commonly occur in people with anxiety disorders.

Structural characteristics of size-controlled self-aggregates of deoxycholic acid-modified chitosan and their application as a DNA delivery carrier

Precise control of the size and structure is one critical design parameter of micellar systems for drug delivery applications. To control the size of self-aggregates, chitosan was depolymerized with various amounts of sodium nitrite, and hydrophobically modified with deoxycholic acid to form self-aggregates in aqueous media. Formation and physicochemical characteristics of size-controlled self-aggregates were investigated using dynamic light scattering, fluorescence spectroscopy, and computer simulation method. The size of self-aggregates varied in the range of 130-300 nm in diameter, and their structures were found to depend strongly on the molecular weight of chitosan ranging from 5 to 200 kDa. Due to the chain rigidity of chitosan molecule, the structure of self-aggregates was suggested to be a cylindrical bamboolike structure when the molecular weight of chitosan was larger than 40 kDa, which might form a very poor spherical form of a birdnestlike structure. To explore the potential applications of self-aggregates as a gene delivery carrier, complexes between chitosan self-aggregates and plasmid DNA were prepared and confirmed by measuring the fluorescence intensity of ethidium bromide and electrophoresis on agarose gels. The complex formation had strong dependency on the size and structure of chitosan self-aggregates and significantly influenced the transfection efficiency of COS-1 cells (up to a factor of 10). This approach to control the size and structure of chitosan-derived self-aggregates may find a wide range of applications in gene delivery as well as general drug delivery applications.

Cognitive effects of insulin in the central nervous system

Evidence has been accumulating recently that the hormone insulin may modulate cognitive activity by acting in the central nervous system. Initially derived from the observation that insulin and insulin receptors are found in specific brain areas, this evidence also includes cognitive assessments of humans in insulin-deficient and insulin-resistant disease states and experimental manipulation of rodent models. Additional support is derived from in vivo and in vitro systems that are used to investigate the neurophysiological basis of learning and memory. This article is a brief review of the literature that suggests a connection between insulin and memory and draws together some of the findings relevant to possible physiological mechanisms for this cognitive effect.

Intracerebroventricular insulin enhances memory in a passive-avoidance task

Previous studies have indicated a possible enhancing effect of hyperinsulinemia on certain cognitive tasks in human subjects. Further, brain areas important in these tasks have high concentrations of insulin receptors, suggesting that insulin might modulate memory by activity at specific central sites. Extending this observation to the laboratory rat would provide a convenient model system for determining factors important for this possible cognitive effect. The present experiment determined whether intracerebroventricular administration of insulin improves memory formation in rats. Long-Evans rats were trained on a step-through passive-avoidance task, in which they were either shocked or not after entering a darkened compartment. After training, the animals received an intracerebroventricular injection of 4 mU insulin, heat-deactivated insulin or saline vehicle. After 24 h, the animals were tested for retention of the task. Rats receiving insulin after being shocked had an increased latency to enter the dark compartment, compared to those rats that had received saline or heat-deactivated insulin after shock. This difference is consistent with an enhanced memory for the negative consequences of entering.

Exposing rats to a predator impairs spatial working memory in the radial arm water maze

This series of studies investigated the effects of predator exposure on working memory in rats trained on the radial arm water maze (RAWM). The RAWM is a modified Morris water maze that contains four or six swim paths (arms) radiating out of an open central area, with a hidden platform located at the end of one of the arms. The hidden platform was located in the same arm on each trial within a day and was in a different arm across days. Each day rats learned the location of the hidden platform during acquisition trials, and then the rats were removed from the maze for a 30-min delay period. During the delay period, the rats were placed either in their home cage (nonstress condition) or in close proximity to a cat (stress condition). At the end of the delay period, the rats were run on a retention trial, which tested their ability to remember which arm contained the platform that day. The first experiment confirmed that the RAWM is a hippocampal-dependent task. Rats with hippocampal damage were impaired at learning the location of the hidden platform in the easiest RAWM under control (non-stress) conditions. The next three experiments showed that stress had no effect on memory in the easiest RAWM, but stress did impair memory in more difficult versions of the RAWM. These findings indicate that the capacity for stress to impair memory is influenced not only by the brain memory system involved in solving the task (hippocampal versus nonhippocampal), but also by the difficulty of the task. This work should help to resolve some of the confusion in the literature regarding the heterogeneous effects of stress on hippocampal-dependent learning and memory.

Exposing rats to a predator impairs spatial working memory in the radial arm water maze

This series of studies investigated the effects of predator exposure on working memory in rats trained on the radial arm water maze (RAWM). The RAWM is a modified Morris water maze that contains four or six swim paths (arms) radiating out of an open central area, with a hidden platform located at the end of one of the arms. The hidden platform was located in the same arm on each trial within a day and was in a different arm across days. Each day rats learned the location of the hidden platform during acquisition trials, and then the rats were removed from the maze for a 30-min delay period. During the delay period, the rats were placed either in their home cage (nonstress condition) or in close proximity to a cat (stress condition). At the end of the delay period, the rats were run on a retention trial, which tested their ability to remember which arm contained the platform that day. The first experiment confirmed that the RAWM is a hippocampal-dependent task. Rats with hippocampal damage were impaired at learning the location of the hidden platform in the easiest RAWM under control (non-stress) conditions. The next three experiments showed that stress had no effect on memory in the easiest RAWM, but stress did impair memory in more difficult versions of the RAWM. These findings indicate that the capacity for stress to impair memory is influenced not only by the brain memory system involved in solving the task (hippocampal versus nonhippocampal), but also by the difficulty of the task. This work should help to resolve some of the confusion in the literature regarding the heterogeneous effects of stress on hippocampal-dependent learning and memory.

Taste aversion learning in fyn mutant mice

Conditioned taste aversion (CTA) learning is a robust form of classical conditioning in which animals rapidly associate a flavor with aversive internal symptoms. The present study assessed CTA learning in transgenic mice deficient in a specific nonreceptor tyrosine kinase (the fyn mutant). Fyn mutants show impaired long-term potentiation and marked deficits in acquisition of spatial learning tasks. To assess whether they are also impaired in CTA learning, fyn mutant and wild-type mice received 2 conditioning trials consisting of access to a flavored solution followed by administration of LiCl. Fyn mutant mice acquired significant CTAs following a single conditioning trial and these aversions were comparable to those seen in wild-type mice. These results indicate that the fyn mutation does not interfere with the acquisition of CTAs and hence that this mutation is not associated with a global learning deficit.

A comparison of the effects of food deprivation and 2,5-anhydro-D-mannitol on metabolism and ingestion

Using respiratory quotient as an index of metabolic state, we compared the effects of administrations of the fructose analogue 2,5-anhydro-D-mannitol (2,5-AM) at a dose of 300 mg/kg with the effect of 10 h of food deprivation. We measured behavioral and physiological responses of the animals receiving the two treatments, including food intake, energy expenditure, rates of carbohydrate and fatty acid utilization, and plasma levels of glucose, insulin, corticosterone, epinephrine, and norepinephrine. A vehicle-treated control group was also included. Fasting produced a greater food intake than 2,5-AM administration. Although plasma glucose, insulin, and norepinephrine levels were similar between the two treatments, plasma corticosterone and epinephrine levels were significantly elevated in animals receiving 2,5-AM. We conclude that although 2,5-AM can produce a metabolic state similar to fasting, as measured by an index of whole body metabolic state (respiratory quotient), there remain factors that influence food intake that are not similar in the two conditions.

The evaluation of insulin as a metabolic signal influencing behavior via the brain

The intent of this paper is to evaluate decreases of food intake and body weight that occur when a peptide is administered to an animal. Using the pancreatic hormone insulin as an example, the case is made that endogenous insulin is normally secreted in response to circulating nutrients as well as in proportion to the degree of adiposity. Hence, its levels in the blood are a reliable indicator of adiposity. A further case is then made demonstrating that insulin is transported through the blood-brain barrier into the brain, where it gains access to neurons containing specific insulin receptors that are important in the control of feeding and metabolism. Finally, experimentally-induced changes of insulin in the brain cause predictable changes of food intake and body weight. Given these observations, the question is then asked: since endogenous insulin, acting within the brain, appears to decrease food intake, can a decrease of food intake caused by exogenous insulin administered into the same area of the brain be ascribed to the same, naturally-occurring response system, or should it be attributed to malaise or a non-specific depression of behavior? Arguments are presented supporting the former position that exogenous insulin, when administered in small quantities directly into the brain, taps into the natural caloric/metabolic system and hence influences food intake and body weight.

Whole body energy expenditure and fuel oxidation after 2,5-anhydro-D-mannitol administration

The fructose analogue 2,5-anhydro-D-mannitol (2,5-AM) increases food intake in nondeprived rats. Several lines of evidence indicate that vagal signals arising from the liver are critical for this effect. In addition, 2,5-AM decreases plasma glucose and increases lipolysis, resulting in an increase in plasma free fatty acids and ketone bodies. In these respects 2,5-AM produces a state analogous to that observed after food deprivation. Using an indirect calorimeter, we determined that 2,5-AM (300 mg/kg ip) causes a potent and long-lasting decrease in respiratory quotient, indicating a decrease in the fraction of total energy derived from carbohydrate oxidation and an increase in the fraction derived from fatty acid oxidation. These metabolic variables were altered without affecting total metabolic rate. This dose of analogue also stimulated significantly greater food intake than injections of vehicle. These results support the continued use of 2,5-AM as a tool to probe the metabolic controls of food intake.

Chronic alcohol consumption increases sensitivity to the anorexic effect of cholecystokinin

In this study we examined the ability of intraperitoneal cholecystokinin COOH-terminal octapeptide (CCK-8; 0.2, 0.6, and 2.0 micrograms/kg) to suppress food intake in rats that had consumed a control diet, 6-8 g.kg-1.day-1 of ethanol (EtOH) in sucrose, or sucrose alone for 6 mo. Both the EtOH- and sucrose-fed rats developed significant dietary obesity. After 3 mo, the EtOH group was significantly more sensitive to CCK-8 than the sucrose and control groups, while the responses of the sucrose and control groups were comparable. In contrast, after 6 mo the EtOH and sucrose groups' response to CCK-8 was no longer significantly different. After 6 mo there were no significant differences in basal or postprandial plasma CCK-8 levels. The sucrose group had significantly higher basal insulin levels than the control and EtOH groups, and postprandial insulin levels, relative to basal, were significantly elevated in the EtOH group. Basal glucose levels did not differ among groups. Postprandial glucose levels (relative to baseline) were significantly lower in the EtOH group compared with the other groups and in fact never rose above baseline levels. These results are consistent with the hypothesis that EtOH, when taken on a chronic basis, increases the sensitivity to CCK-8.

Effect of meal pattern during food restriction on body weight loss and recovery after refeeding

The present study was designed to assess whether the pattern of meal feeding and the degree of caloric restriction have an effect on the body weights and refeeding patterns of restricted 4-month-old Long-Evans rats, relative to ad lib-fed controls. Four experimental groups of rats (n = 6 each) were put on different paradigms of food restriction, and a fifth group fed ad lib throughout served as controls. Twelve rats were restricted to receiving 50% of their mean baseline food intake, and 12 rats received only 70% of their baseline food intake. Each experimental group was further subdivided with one subgroup receiving all of their calories in one meal/day and the other with caloric intake equally divided into two meals/day. There was no statistical difference in the final body weights of the restricted groups. Although there appeared to be identical patterns of weight regain, none of the restricted groups ever reached the mean body weight of the controls because of an asymptotic leveling off of rate of body weight regain. Rats that had received 50% of baseline calories as two meals/day had significantly more adipose mass than did any other group. The present findings suggest that in the rat, refeeding and, hence, regulation, occurs to normalize rate of weight gain rather than absolute body weight.

Effect of diet-induced obesity and experimental hyperinsulinemia on insulin uptake into CSF of the rat

We examined the hypothesis that the uptake of plasma insulin into cerebrospinal fluid (CSF) is saturable in two rat models. Dietary obese and control female Osborne Mendel rats received 24-h infusions of vehicle or insulin. CSF insulin levels in cafeteria- and chow-fed rats were comparable at all levels of plasma insulin (4.5 +/- 2.8, 7.6 +/- 2.4, and 23.9 +/- 6.4 microU/ml in cafeteria diet vs. 4.5 +/- 0.9, 6.8 +/- 1.1, and 17.0 +/- 4.0 microU/ml in chow rats). CSF insulin uptake as a percentage of plasma insulin decreased with increased plasma insulin in both groups. A similar relationship was observed in Wistar rats receiving 6-day infusions of vehicle or insulin (plasma insulin = 55 +/- 12 vs. 365 +/- 98 microU/ml; CSF/plasma insulin ratio = 0.022 +/- .007 vs. 0.013 +/- .006, respectively). Hyperinsulinemic Wistar rats did not demonstrate decreased brain capillary insulin binding vs. vehicle-infused controls. The results suggest that a saturable transport process contributes insulin transport into CSF in normal rats and that this process is not altered by moderate diet-induced obesity or hyperinsulinemia per se.

Intraventricular insulin reduces food intake and body weight of marmots during the summer feeding period

The study presented below describes experiments that investigate the ability of insulin to inhibit food intake in awake, active marmots during the summer season. Our results suggest that increasing intraventricular insulin concentration during the summer active feeding period will cause a decrease in food intake and body weight of marmots. When infused with insulin into their lateral ventricles (Alzet #2002 minipumps), animals had significantly lower food intake as compared to their food intake during the control period. In addition, these animals lost body weight during the period of the insulin infusion. We suggest that during the summer when marmots are not hibernating and are actively feeding, brain insulin levels may play a role in regulating food intake.

Energy metabolism of the untrained muscle of elite runners as observed by 31P magnetic resonance spectroscopy: evidence suggesting a genetic endowment for endurance exercise

The purpose of this study was to investigate whether genetically determined properties of muscle metabolism contribute to the exceptional physical endurance of world-class distance runners. ATP, phosphocreatine, inorganic phosphate, and pH were quantitatively determined by 31P nuclear magnetic resonance spectroscopy in the wrist flexor muscles of elite long-distance runners and sedentary control subjects. These muscles had not been exposed to any specific program of exercise training in either group of subjects. The "untrained" muscles were examined at rest, during two cycles of three grades of exercise, and in recovery. The flexor muscles of the athletes had higher concentrations of phosphocreatine and ATP than did those of the control subjects at rest and during exercise. The athletes' muscles possessed a higher capacity for generation of ATP by oxidative metabolism than did control subjects' muscles according to the following criteria: (i) high force output, 60% of maximum voluntary contraction, was more easily reached and better maintained in both exercise cycles; (ii) the ratio of inorganic phosphate to phosphocreatine rose less during exercise and recovered faster in the postexercise period; (iii) there was no loss of adenine nucleotides or total phosphate from the athletes' muscles but significant losses from the control subjects' muscles; and (iv) the pH decreased no more than 0.1 unit in the athletes' muscles during exercise, attesting to a relatively slow glycolysis and/or a rapid oxidation of lactate. In the muscles of the control subjects, on the other hand, the pH decreased nearly 0.4 unit early in the first exercise cycle, indicating a relatively fast glycolysis and/or slower oxidation of lactate. In the second exercise cycle, the pH returned to near normal in the control subjects' muscles, reflecting diminished lactate formation because of glycogen depletion and lactate washout by the high blood flow induced by exercise. By the end of the exercise program, the maximum voluntary contractile force for the control subjects had declined to less than 60% of the initial value. This decline could be explained best by exhaustion of the glycolytic contribution to muscle contraction. Therefore, the residual maximum strength provided a measure of the oxidative capacity to support contraction, as is discussed. In conclusion, we suggest that a greater oxidative capacity relative to glycolytic capacity for support of contraction in untrained muscle of world-class runners reflects a genetic endowment for physical endurance. Additional systemic effects of training cannot be completely excluded. 31P magnetic resonance spectroscopy provides a noninvasive method for assessing this endowment.

Functional pools of oxidative and glycolytic fibers in human muscle observed by 31P magnetic resonance spectroscopy during exercise

Quantitative probing of heterogeneous regions in muscle is feasible with phosphorus-31 magnetic resonance spectroscopy because of the differentiation of metabolic patterns of glycolytic and oxidative fibers. A differential recruitment of oxidative and glycolytic fibers during exercise was demonstrated in 4 of 10 untrained young men by following changes in phosphate metabolites. Concentrations of inorganic phosphate (Pi), phosphocreatine, and ATP were estimated in the wrist flexor muscles of the forearm at rest, during two cycles of three grades of exercise, and in recovery. At high work levels (40% of maximum strength), two distinct Pi peaks were observed and identified with Pi pools at pH 6.9 and pH 5.9-6.4, respectively. These could be accounted for as follows. At the lowest level of work (using 20% of maximum strength), early recruitment primarily of oxidative (type I) and possibly some intermediate (type IIA) muscle fibers occurs with relatively little net lactate production and consequently little decrease in pH. At higher work loads, however, primarily glycolytic (type IIB) muscle fibers are recruited, which have relatively high net lactate production and therefore generate a second pool of Pi at low pH. ATP depletion (35-54%) and Pi losses accompanied the reduction in ability to perform during the first exercise cycle. When the cycle of graded exercise was repeated immediately, the total Pi remained high but gave rise to only one peak at pH 6.8-7.0. These observations indicated exhaustion of glycolytic type IIB fibers, removal of lactate by high local blood flow, and sustained contractions largely by oxidative type I and IIA fibers. A functional differentiation of fiber types could also be demonstrated during recovery if exercise was stopped while two pools of Pi were still apparent. In the first 3 min of recovery, the Pi peak at pH 6.8-6.9 disappeared almost entirely, whereas the Pi peak at pH 6.0 remained unaltered, reflecting the faster recovery of oxidative type I fibers. The potential of magnetic resonance spectroscopy to characterize oxidative and glycolytic fibers, predict capacity for aerobic performance, and signal the presence of muscle pathology is discussed.

Interactions of vitamin E and penicillamine in the treatment of hereditary avian muscular dystrophy

Our prior work demonstrated that penicillamine treatment of dystrophic chickens delayed the onset of symptoms, partially alleviated contractures, improved muscle function, and lowered serum creatine kinase. Penicillamine, a sulfhydryl compound with reducing properties, also prevented inactivation of glycolytic enzymes by protecting thiol groups. The present study shows that vitamin E enhances the therapeutic effects of penicillamine. Interaction of these two reductants is dose related. With vitamin E as adjunct therapy, the dosage level of penicillamine could be lowered by 50%, thereby minimizing side effects. The therapeutic rationale for two antioxidants is that penicillamine may act primarily in the cytoplasm to prevent oxidative damage, whereas the more hydrophobic vitamin E may protect membrane bilayers. Additionally, penicillamine may prevent collagen cross-linking and, deposition of insoluble collagen in muscle and thus decrease contracture formation. General applications of combined penicillamine and vitamin E therapy are discussed regarding prevention of free radical and oxidative damage in Duchenne dystrophy and a wide range of human diseases.

Catecholamine activation of the membrane transport of long chain fatty acids in adipocytes is mediated by cyclic AMP and protein kinase

Membrane transport of long chain fatty acids in the isolated adipocyte can be stimulated 5-10-fold by epinephrine (Abumrad, N. A., Perry, P. R., and Whitesell, R. R. (1985) J. Biol. Chem. 260, 9969-9971). This study shows that isoproterenol and norepinephrine are more potent than epinephrine in activating the transport process. The stimulatory effect on transport is mediated by beta-receptor interaction and cAMP. This was shown by the following. alpha-Receptor agonists and antagonists were ineffective; methylisobutylxanthine at low concentration (3 microM) potentiated the effect of a suboptimal dose (0.01 microgram/ml) of epinephrine and was stimulatory at high concentration (100 microM) in the absence of epinephrine; and cAMP analogs were very effective activators. Involvement of the cAMP-dependent protein kinase was indicated by two lines of evidence. 1) Combinations of cAMP analogs which are specific for sites 1 and 2 of the protein kinase, respectively, had synergistic effects on fatty acid transport. Combinations of analogs specific for the same site were only additive in their effects. This is similar to the pattern of protein kinase activation in vitro and to that of lipolysis activation in the intact adipocyte (Beebe, S. J., Holloway, R., Rannels, S. R., and Corbin, J. D. (1984) J. Biol. Chem. 259, 3539-3547). 2) Treatment of cells with various metabolic poisons abolished the stimulatory effect of norepinephrine. The response of fatty acid transport to catecholamines showed multiple parallels with that documented for lipolysis except that it was much more rapid. This suggested that the transport process was a regulatory step in fatty acid mobilization. This interpretation is supported by the observation that basal Vmax for transport is much too slow to accommodate the rate of fatty acid release which is observed following stimulation of intact cells with adrenergic hormones.

Permeation of long-chain fatty acid into adipocytes. Kinetics, specificity, and evidence for involvement of a membrane protein

This study extends our earlier work (Abumrad, N. A., Perkins, R.C., Park, J.H., and Park, C.R. J. Biol. Chem. 256, 9183-9191) which showed that oleate permeates the plasma membrane of the rat adipocyte principally by a transport process with the characteristics of facilitated diffusion. In the present study, fatty acid (FA) transport is characterized with regard to its specificity and susceptibility to inhibition by protein modifiers. The kinetics of competitive inhibition for transport of oleate and stearate are shown under conditions where complications due to competition for binding of FAs to the albumin in the medium are minimized. Stearate inhibits influx of tracer oleate with a Ki that closely approximates its Km and, conversely, oleate inhibits similarly the influx of tracer stearate. Specificity of the FA transport system is shown in studies using a variety of natural FAs of different chain length, or FA analogues. Oleate (Km = 0.06 microM), stearate (Km = 0.16 microM), linoleate (Km = 0.22 microM), palmitate, (Km = 0.2 microM), and laurate (Km = 1.5 microM) are good substrates, but octanoate is not transported. An oxazolidine ring on C-5 but not on C-16 of stearate blocks binding to the transporter. Methylation of the carboxyl function but not alpha-bromination inhibits transport. These studies suggest that a FA must have a hydrocarbon chain of at least nine carbons and a free carboxyl function to be recognized by the transporter. FA transport does not require Na or ATP. Pronase but not trypsin treatment of intact cells reduces fatty acid influx. Transport is insensitive to maleimides. It is strongly and irreversibly blocked by pretreatment of the cells with the stilbene compounds, 4,4'-diisothiocyanostilbene-2,2'-disulfonate and 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid, but only slightly inhibited by dipyridamole. Polyacrylamide gel electrophoresis of plasma membrane proteins from cells treated with [3H] 4,4'-diisothiocyanostilbene-2,2'-disulfonate shows a peak of radioactivity at about Mr = 85,000. When cells are incubated in various concentrations of this agent, the counts recovered in the peak reach a maximum coincident with maximum inhibition of transport. We conclude that permeation of the plasma membrane of the adipocyte by long-chain FAs at physiological concentrations is mediated by a protein transporter with distinct specificity requirements.

Equilibrium binding of spin-labeled fatty acids to bovine serum albumin: suitability as surrogate ligands for natural fatty acids

Electron paramagnetic resonance (EPR) and saturation transfer EPR (ST-EPR) spectroscopies were used to characterize the binding of spin-labeled fatty acid (SLFA) to bovine serum albumin (BSA). Association constants of three stearic acid derivatives labeled with a nitroxyl radical at C-5, C-12, or C-16 were estimated by EPR spectroscopy as the ratio of SLFA to BSA was increased from about 0 to 9. The values were compared to those for unmodified stearate. With all three SLFA, it was apparent that the nitroxyl residue modified the binding pattern. For SLFA:BSA ratios up to 1, which probably involves the site(s) on BSA most specific for long-chain FA, the C-16 derivative bound with an affinity similar to that of the natural FA. At higher ratios, the association constants for this SLFA were lower than those for stearate. The C-12 and C-5 derivatives showed only low-affinity binding relative to stearate. The spectral parameter, W, was constant for SLFA:BSA ratios between 0 and 1 in the case of C-16 compound, indicating physical homogeneity of the high-affinity binding site. At higher ratios, the spectra changed progressively, indicating inhomogeneity of the lower affinity binding sites although parallel changes in association constants were not observed. Changes in W due to Heisenberg spin exchange were ruled out. By examining the mobility profile of the bound SLFA by both EPR and ST-EPR techniques, it was shown that the nitroxyl group was maximally immobilized when attached near the center of the carbon chain of the bound SLFA.