bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of aqueous Enicostemma littorale Blume extract on key carbohydrate metabolic enzymes, lipid peroxides and antioxidants in alloxan-induced diabetic rats
Authors: Srinivasan M , Padmanabhan M , Prince P Stanely Mainzen 
Published: March 2005

Abstract
The present study investigates the effect of oral administration of an aqueous Enicostemma littorale whole plant extract on some key carbohydrate metabolic enzymes and antioxidant defence in alloxan-induced diabetes in rats. Rats were rendered diabetic by alloxan (150 mg kg−1 body weight) administration. Oral administration of E. littorale extract for 45 days increased the activity of hexokinase and decreased the activities of glucose 6-phosphatase and fructose 1,6-bisphosphatase significantly in the serum, liver and kidney of diabetic rats. The extract lowered the concentration of thiobarbituric acid reactive substances and lipid hydroperoxides significantly in brain and increased it significantly in heart in diabetic rats. E. littorale administration increased the concentration of reduced glutathione and the activity of glutathione peroxidase in diabetic rats. The activities of superoxide dismutase and catalase were increased significantly by E. littorale treatment in diabetic rats. The effect of a 2 g kg−1 dose was greater than that of a 1 g kg−1 dose. Insulin (6 units kg−1) normalized all the parameters in diabetic rats. Our study has provided evidence for the antidiabetic activity of E. littorale aqueous extract. This study can also be extrapolated to clinical studies in future.
Nifedipine enhances cGMP production through the activation of soluble guanylyl cyclase in rat ventricular papillary muscle
Authors: Seya Kazuhiko , Furukawa Ken-Ichi , Yoshida Kazuhiko , Narita Reina , Motomura Shigeru 
Published: March 2005

Abstract
It is known that nifedipine, an L-type calcium channel blocker, increases cGMP production, which partially contributes to the relaxation of vascular smooth muscle. The aim of our investigation was to clarify whether or not nifedipine regulates cGMP production, which has a physiological role in cardiac muscle. To measure contractile responses and tissue cGMP levels, left ventricular papillary muscles prepared from male Wistar rats (350–400 g) were mounted in the isolated organ chamber under isometric conditions and electrically paced by means of platinum punctate electrodes (1 Hz, 1 ms duration). In papillary muscle preparation, the negative inotropic effect induced by nifedipine (30 to 300 nm) was significantly inhibited in the presence of ODQ (1H-[1,2,4]oxidazolo[4,3-a]quinoxaline-1-one; 10 μm), a soluble guanylyl cyclase inhibitor. Furthermore, nifedipine (100 nm) strongly increased the tissue cGMP level, which was significantly decreased in the presence of ODQ. On the other hand, NG-monomethyl-l-arginine (100 μm), a nitric oxide synthase inhibitor, did not inhibit either the negative inotropic effect or cGMP production induced by nifedipine. These results indicate that in rat left ventricular papillary muscle, nifedipine augments its negative inotropic effect at least partly through direct activation of cardiac soluble guanylyl cyclase but not nitric oxide synthase.
Selective β1-adrenoreceptor blocking activity of newly synthesized acyl amino-substituted aryloxypropanolamine derivatives, DPJ 955 and DPJ 890, in rats
Authors: Nandakumar K , Bansal S K , Singh Randhir , Bodhankar S L , Jindal D P , Coumar Mohane S , Balaraman R , Bhardwaj S H 
Published: March 2005

Abstract
The in-vivo β-adrenoreceptor antagonistic activity of test compounds DPJ 955 and DPJ 890 was assessed against β-adrenoreceptor agonist (isoprenaline) induced tachycardia in anaesthetized rats. The selectivity to block isoprenaline responses on different β-adrenoreceptor subtypes (β1, β2 and β3) of the test compounds was carried out on isolated rat right atria, isolated rat uterus and isolated rat colon preparations, respectively. Intravenous injection of isoprenaline alone in anaesthetized rats caused hypotension and tachycardia. DPJ 955 or DPJ 890 alone produced a fall in mean arterial pressure and bradycardia in a dose-dependent manner. Administration of isoprenaline to anaesthetized rats pre-treated with test compounds significantly blocked both the tachycardial and hypotensive responses induced by isoprenaline. The test compounds shifted the concentration response curves of isoprenaline towards the right for isolated rat right atrial preparations, rat uterus and rat colon, indicating β1, β2 and β3 adrenoreceptor blockade, respectively. The selectivity ratio for β1/β-adrenoreceptors to DPJ 955 and DPJ 890 was 64.6 and 83.2, respectively. DPJ 890 was more potent in blocking β1-adrenoreceptors and was more selective towards β1 receptors than to other β-adrenoreceptor subtypes. In conclusion, DPJ 955 and DPJ890 have β-adrenoreceptor blocking activity with high selectivity for the β1-adrenoreceptor subtype.
Mechanism of cell death induced by cationic dendrimers in RAW 264.7 murine macrophage-like cells
Authors: Kuo Jung-hua Steven , Jan Ming-shiou , Chiu Hsuan Wen 
Published: March 2005

Abstract
Cationic dendrimers possess attractive nano-sized architectures that make them suitable as targeted drug/gene delivery systems. However, very little is known about their mechanisms of cell death in cellular systems. In the current study, the apoptotic and necrotic effects of starburst polyamidoamine (PAMAM) and polypropylenimine (DAB) dendrimers in cultured RAW 264.7 murine macrophage-like cells were investigated. Cationic dendrimer treatment produced a typically dose-dependent cytotoxic effect on macrophage cells. RAW 264.7 cells exposed to cationic dendrimers exhibited morphological features of apoptosis. Apoptotic ladders were observed in DNA extracted from RAW 264.7 cells treated with cationic dendrimers. Analysis from flow cytometry demonstrated an increase in hypodiploid DNA population (sub-G1) and a simultaneous decrease in diploid DNA content, indicating that DNA cleavage occurred after exposure of the cells to cationic dendrimers. Also, cells treated with DAB dendrimer induced a higher percentage of sub-G1 population than those treated with PAMAM dendrimer at the same dose. In addition, it was shown that pre-treatment of RAW 264.7 cells with the general caspase inhibitor zVAD-fmk prevented some degree of apoptosis induced by cationic dendrimers, suggesting that apoptosis in macrophage cells involves a caspasedependent pathway. Macrophage cells were also found to be sensitive to induction of apoptosis by dendrimers, whereas NIH/3T3 cells (mouse fibroblast) and BNL CL.2 (mouse liver) cells did not undergo apoptosis. These results could be helpful for optimizing the biocompatibility of dendrimers used for targeted drug/gene delivery.
Citrus extract modulates genotoxicity induced by cyclophosphamide in mice bone marrow cells
Authors: Hosseinimehr Seyed Jalal , Karami Mohmmad 
Published: March 2005

Abstract
The protective effect of citrus extract was investigated by using the micronucleus assay for anticlastogenic activity in mouse bone marrow cells; liver glutathione (GSH) content was determined against toxicity induced by cyclophosphamide. Mice were orally (gavage) pretreated with solutions of citrus peel extract (Citrus aurantium var. amara) prepared at three different doses (100, 200 and 400 mg kg−1 body weight) for 7 consecutive days. Then mice were injected intraperitoneally on the seventh day with cyclophosphamide (50 mg kg−1) and after 24 h killed for the evaluation of micronucleated polychromatic erythrocytes (MnPCEs) in bone marrow cells. Non-protein thiol levels in liver were estimated in mice injected with citrus extract with or without cyclophosphamide treatment. Administration of citrus extract before cyclophosphamide treatment significantly reduced the frequency of MnPCEs in mice bone marrow compared with the group treated with cyclophosphamide alone (P&lt;0.0001–0.05). Citrus extract at a dose of 400 mg kg−1 reduced MnPCEs 2.8 fold against genotoxicity induced by cyclophosphamide. Administration of cyclophosphamide depleted the GSH level in liver. Citrus extract showed excellent scavenging effects on 1,1-diphenyl-2-picryl hydrazyl radical (DPPH) at a concentration of 1.6 mg mL−1. Application of citrus extract 1 h before cyclophosphamide treatment allowed GSH content to reach the normal level. It appeared that citrus extract, particularly flavonoids constituents with antioxidative activity, may return the GSH level to normal in stress conditions and reduces genotoxicity induced by cyclophosphamide in bone marrow cells.
Experimental modelling of drug membrane permeability by capillary electrophoresis using liposomes, micelles and microemulsions
Authors: Örnskov Eivor , Gottfries Johan , Erickson Magnus , Folestad Staffan 
Published: March 2005

Abstract
Capillary electrophoresis (CE) was evaluated as an in-vitro format for experimental modelling of membrane permeability using only nanogram quantities of drug compounds. The rationale for the CE technique emanates from emulation of a lipid-like pseudo-stationary phase that governs separations mainly as a result of differences in molecular size, lipophilicity, hydrogen bonding and charge, all of which also have a strong influence on in-vivo drug absorption. By means of micellar, microemulsion and liposome electrolytes, the migration behaviour was studied at 37°C for 22 model drug compounds. The generated CE retention factor data were then compared with membrane permeability reference data. Both simple log D and more common Caco-2 cell parameters were evaluated. In addition, permeation through intestinal segments of rat ileum and rat colon was included. An improved correlation was obtained in the order: micellar&lt;microemulsion&lt;liposome systems. Although the correlation for the best liposome CE system was only R2 = 0.77, the evaluation results for all emphasized the strength and flexibility of CE for assessing specific drug-membrane interaction through tailor-made lipophilic media.
Tumour targeting: biological factors and formulation advances in injectable lipid nanoparticles
Authors: Shenoy V S , Vijay I K , Murthy R S R 
Published: March 2005

Abstract
Cancer chemotherapeutic agents are often administered systemically. Following systemic administration, numerous biological factors associated with the tumours influence the delivery of the drugs to the tumours. These factors have been extensively studied for the last 2 decades. The influence of these biological factors has brought about a drastic change in the design of drug delivery systems to solid tumours. This review discusses the various biological factors influencing drug delivery to tumours and the subsequent development of injectable delivery systems (i.e., lipid-based nanoparticles (SLNs)) for adequate delivery of drug to solid tumours.
Decompressive Hemicraniectomy for Acute Disseminated Encephalomyelitis: Case Report
Authors: Refai Daniel , Lee Max C. , Goldenberg Fernando D. , Frank Jeffrey I. 
Published: March 2005

Abstract

OBJECTIVE AND IMPORTANCE:
Acute disseminated encephalomyelitis (ADEM) varies widely in symptoms and severity. Some cases are associated with massive life-threatening cerebral edema refractory to conventional medical management.

CLINICAL PRESENTATION:
A 51-year-old woman with ADEM who developed severe brain swelling and herniation despite aggressive medical management is described.

INTERVENTION:
A decompressive hemicraniectomy and durotomy led to rapid improvement and an excellent outcome.

CONCLUSION:
This case report reinforces the place of this procedure in the armamentarium of treatment options for patients with medically refractory brain swelling and elevated intracranial pressure caused by ADEM. The potential for an increase in the incidence of ADEM with more frequent smallpox vaccinations emphasizes the significance of redefining the full range of management options for this treatable disease.
Surgical Outcome in Rheumatoid Ranawat Class IIIb Myelopathy
Authors: Nannapaneni Ravindra , Behari Sanjay , Todd Nicholas V. 
Published: March 2005

Abstract

OBJECTIVE:
Rheumatoid arthritis frequently affects the craniovertebral junction (CVJ) and may lead to severe neck pain, quadriparesis, and respiratory dysfunction. Surgery in rheumatoid nonambulatory (Ranawat Class IIIb) patients carries a significant risk. This study presents the surgical outcome of Class IIIb patients with CVJ rheumatoid myelopathy and reviews the literature.

METHODS:
One hundred twelve consecutive patients with rheumatoid cervical myelopathy underwent surgical decompression and stabilization. Thirty-two of the patients (mean age, 66.81 ± 10.25 yr) with CVJ rheumatoid arthritis were in Class IIIb, and all had atlantoaxial subluxation. A halo brace was applied before surgery and continued during surgery. Eleven patients with reducible atlantoaxial subluxation underwent direct posterior fusion. Twenty-one patients with fixed atlantoaxial subluxation underwent transoral decompression and then posterior fusion while they were under anesthesia.

RESULTS:
At a mean follow-up of 39 months, four patients improved to Class II and 14 improved to Class IIIa, whereas six remained in Class IIIb. Neck pain was relieved in all patients. There was one perioperative death after transoral surgery (posterior fusion not done), and seven other patients died subsequently of causes unrelated to surgery. The morbidity of surgery included construct failure, cerebrospinal fluid leak, superficial wound or graft donor site infection, transient dysphagia, and lung infection.

CONCLUSION:
A large subset of patients with CVJ rheumatoid myelopathy may reach Class IIIb. These patients have unique management considerations. Surgery (despite high morbidity) often remains the best therapeutic option available to them. Improvement of even one grade in their Ranawat score from Class IIIb to Class IIIa brought about by surgery confers on them a significant benefit in terms of their quality of life and survival.
Assessment of the Learning Curve for Lumbar Microendoscopic Discectomy
Authors: Nowitzke Adrian M. 
Published: March 2005

AbstractOBJECTIVE:An understanding of the learning curve of a new surgical procedure is essential for its safe clinical integration, teaching, and assessment. This knowledge is currently deficient for lumbar microendoscopic discectomy (MED). The present article aims to profile the learning curve for MED of an individual surgeon in a hospital not previously exposed to this procedure.METHODS:The first 35 cases of MED for posterolateral lumbar disc prolapse causing radiculopathy performed at the Princess Alexandra Hospital, Brisbane, Australia, were studied prospectively. The learning curve was assessed using surgery time, conversion rate, complication rate, surgeon “comfort,” and key learning steps.RESULTS:The duration of surgical operating time decreased over the course of the study, initially rapidly and then more gradually. There were three conversions to open discectomy in the first 7 cases and none in the next 28 cases. The complexity of cases increased over the series, and the complication rate decreased. The asymptote of the learning curve seems to be approximately 30 cases. The specific learning tasks of MED include lateral lamina radiology, scope vision, visuospatial orientation, smaller field of view, angle of approach and tube position, and care and handling of endoscope equipment.CONCLUSION:A learning curve for MED has been demonstrated. Further assessment of this curve for a population of surgeons is necessary before a clinical assessment of open discectomy versus MED can be embarked upon.
Surgical Site Infections after Pediatric Intracranial Surgery for Craniofacial Malformations: Frequency and Risk Factors
Authors: Yeung Laurence C. , Cunningham Michael L. , Allpress Amanda L. , Gruss Joseph S. , Ellenbogen Richard G. , Zerr Danielle M. 
Published: March 2005

Abstract

OBJECTIVE:
Surgical site infections (SSIs) after pediatric intracranial surgery for craniofacial malformations are relatively common and potentially serious nosocomial infections. Despite this, few studies have been published on this topic. We performed a retrospective study to determine the incidence of and factors associated with SSIs after intracranial surgery for craniofacial malformations at a single multidisciplinary craniofacial center during a 6-year period.

METHODS:
Retrospective chart review was performed on 254 patients who underwent 281 intracranial procedures during a 6-year period. Patients with SSIs (cases) were compared with those without SSIs (controls). National Nosocomial Infection Surveillance System criteria were used to identify cases of SSI.

RESULTS:
SSIs occurred in 9 (3.2%) of 281 intracranial procedures that took place during the study period. Factors associated with an SSI included a complicated diagnosis comprising a diagnosis of syndromic craniosynostosis, frontonasal dysplasia, or oblique facial cleft (odds ratio [OR], 13.0; 95% confidence interval [CI], 2.6–64.4); duration of surgery longer than 426 minutes (OR, 12.1; 95% CI, 2.4–59.9); closure of skin under tension (OR, 12.5; 95% CI, 3.0–52.6); use of bovine pericardium (OR and 95% CI undefined); more than four surgeons present during surgery (OR, 6.3; 95% CI, 1.2–32); pediatric intensive care unit stay longer than 2 days (OR, 10.8; 95% CI, 2.2–53.3); and use of a ventilator after surgery (OR, 4.8; 95% CI, 1.2–18.6).

CONCLUSION:
In this study, the presence of a complicated diagnosis and a number of other factors were associated with an SSI after pediatric intracranial surgery for craniofacial malformations. We speculate that a complicated diagnosis may be a marker for other factors that contribute to the risk of an SSI. Future studies investigating SSIs after intracranial surgery should consider these factors.
Bilateral Reversible Deafness after Surgery for Unilateral Epidermoid Tumor: An Unusual Complication: Case Report
Authors: Colpan Mustafa Efkan , Sekerci Zeki , Berk Caglar 
Published: March 2005

Abstract

OBJECTIVE AND IMPORTANCE:
We present an unusual complication of bilateral hearing loss after surgery for unilateral epidermoid tumor situated at the right pontocerebellar junction. The neurosurgeon must know the possible causes of this catastrophic complication and should take every possible measure to avoid it.

CLINICAL PRESENTATION:
A 43-year-old male patient presented with progressive hearing loss in the right ear. A radiological examination demonstrated a mass lesion at the right pontocerebellar junction. A pure tone audiogram revealed sensorineural hearing impairment of the right ear. A brainstem auditory evoked potential test confirmed this with reduced amplitudes and a prolonged I–V interval.

INTERVENTION:
The patient was operated on via a right paramedian suboccipital craniectomy. The tumor was completely excised, and all of the cranial nerves were preserved during the operation. Postoperatively, the patient developed total bilateral hearing loss, which improved significantly over time.

CONCLUSION:
Controlled cerebrospinal fluid drainage during exposure and tumor excision may reduce the possibility of shift and traction on the neural structures and help to prevent ischemic injury. Frequent irrigation of the surgical field and minimizing the spilling of the tumor contents may reduce the risk of chemical irritation. The use of corticosteroids may also help during the postoperative period.
Factors Associated with Outcome after Hemicraniectomy for Large Middle Cerebral Artery Territory Infarction
Authors: Curry William T. , Sethi Manish K. , Ogilvy Christopher S. , Carter Bob S. 
Published: March 2005

AbstractOBJECTIVE:Large or malignant middle cerebral artery infarction is associated with a high mortality rate. Hemicraniectomy reduces intracranial pressure and has been demonstrated to increase survival. Questions remain regarding selection of patients for surgery and functional outcomes.METHODS:We retrospectively reviewed the charts, operative reports, and images of patients who underwent hemicraniectomy for cerebral infarction at our institution between 1990 and 2002. Stroke volume and craniectomy area image analyses were performed with National Institutes of Health Image J software. Short-term outcome was measured with the Glasgow Outcome Scale. The requirement for second surgical decompression was also used as a measure of short-term outcome. Outcome 1 year after stroke was assessed with mailed self-report questionnaires to patients or providers with answers yielding information pertinent to the Barthel Index for physical disability, the Reintegration to Normal Living Index, and the Zung Depression Index. Univariate and multivariate logistic regression analyses were used to consider factors associated with outcome.RESULTS:Thirty-eight patients with large hemispheric infarcts (average volume, 407 cm3) were treated with hemicraniectomy during the study period. Thirty-two patients survived more than 1 year after surgery. Twenty patients responded to a questionnaire scoring late physical disability (Barthel Index), quality of life (Reintegration to Normal Living Index), and depression (Zung Depression Index). The average Barthel Index score was 67. Barthel Index score and ability to walk were strongly correlated with age but not time to surgery, volume of infarction, or craniectomy size. Patients exhibited moderate to severe decrements in quality of life and increased incidence of depression across all age groups. Reoperation, an indicator for early operative failure, was required in six patients. These patients were significantly younger and had significantly higher volumes of cerebral infarction.CONCLUSION:Hemicraniectomy is life-saving treatment for large middle cerebral artery infarction. Good functional outcomes can be obtained but are less likely in older patients. Younger patients with large-volume strokes may benefit from multiple decompressions, if necessary.
Radiosurgery for Cranial Base Chordomas and Chondrosarcomas
Authors: Krishnan Sunil , Foote Robert L. , Brown Paul D. , Pollock Bruce E. , Link Michael J. , Garces Yolanda I. 
Published: March 2005

Abstract

OBJECTIVE:
To evaluate the efficacy and toxicity of radiosurgery in the treatment of cranial base chordoma and chondrosarcoma.

METHODS:
We reviewed 29 patients with cranial base chordoma (n = 25) or chondrosarcoma (n = 4) who underwent stereotactic radiosurgery between September 1990 and December 2002. The median patient age was 45 years (range, 10–81 yr). Nineteen patients also had radiation therapy before or in conjunction with radiosurgery (median dose, 50.4 Gy). The median tumor volume was 14.4 cm3 (range, 0.6–65.1 cm3). The median tumor margin dose was 15 Gy (range, 10–20 Gy); the median maximum radiation dose was 30 Gy (range, 20–40 Gy). Median clinical and imaging follow-up periods were 4.8 and 4.5 years, respectively.

RESULTS:
Seven chordoma patients (28%) had tumor progression (in-field, n = 3; out-of-field, n = 4), whereas 18 had stable disease or tumor shrinkage. No patient with a chondroid chordoma had tumor enlargement. The actuarial tumor control rates were 89 and 32% at 2 and 5 years, respectively. All 4 patients with chondrosarcoma had tumor control. Clinically, 7 patients (24%) had improvement of pretreatment symptoms, 16 (55%) remained stable, and 6 (21%) worsened. Three patients with tumor progression died. Ten patients (34%) had radiation-related complications. Complications included cranial nerve deficits (n = 6), radiation necrosis (n = 5), and pituitary dysfunction (n = 3). Patients having radiosurgery alone had no toxicity.

CONCLUSION:
Cranial base chordomas and chondrosarcomas remain a formidable management challenge. Radiosurgery as an adjunct to surgical resection provides in-field tumor control for some patients, but radiation-related complications are relatively high, especially when radiosurgery is combined with fractionated radiation therapy.