bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging plant cell death: GFP-Nit1 aggregation marks an early step of wound and herbicide induced cell death
Authors: Cutler Sean R , Somerville Chris R
Published: March 2005

Background

A great deal is known about the morphological endpoints of plant cell death, but relatively little is known about its sequence of events and / or its execution at the biochemical level. Live cell imaging using GFP-tagged markers is a powerful way to provide dynamic portraits of a cellular process that can in turn provide a descriptive foundation valuable for future biochemical and genetic investigations.

Results

While characterizing a collection of random GFP-protein fusion markers we discovered that mechanical wounding induces rapid aggregation of a GFP-Nitrilase 1 fusion protein in Arabidopsis cells directly abutting wound sites. Time-lapse imaging of this response shows that the aggregation occurs in cells that subsequently die 30 – 60 minutes post-wounding, indicating that GFP-Nit1 aggregation is an early marker of cell death at wound sites. Time-lapse confocal imaging was used to characterize wound-induced cell death using GFP-Nit1 and markers of the nucleus and endoplasmic reticulum. These analyses provide dynamic portraits of well-known death-associated responses such as nuclear contraction and cellular collapse and reveal novel features such as nuclear envelope separation, ER vesiculation and loss of nuclear-lumen contents. As a parallel system for imaging cell death, we developed a chemical method for rapidly triggering cell death using the herbicides bromoxynil or chloroxynil which cause rapid GFP-Nit1 aggregation, loss of nuclear contents and cellular collapse, but not nuclear contraction, separating this response from others during plant cell death.

Conclusion

Our observations place aggregation of Nitrilase 1 as one of the earliest events associated with wound and herbicide-induced cell death and highlight several novel cellular events that occur as plant cells die. Our data create a detailed descriptive framework for future investigations of plant cell death and provide new tools for both its cellular and biochemical analysis.
Practical considerations for estimating clinical trial accrual periods: application to a multi-center effectiveness study
Authors: Carter Rickey E , Sonne Susan C , Brady Kathleen T
Published: March 2005

Background

Adequate participant recruitment is vital to the conduct of a clinical trial. Projected recruitment rates are often over-estimated, and the time to recruit the target population (accrual period) is often under-estimated.

Methods

This report illustrates three approaches to estimating the accrual period and applies the methods to a multi-center, randomized, placebo controlled trial undergoing development.

Results

Incorporating known sources of accrual variation can yield a more justified estimate of the accrual period. Simulation studies can be incorporated into a clinical trial's planning phase to provide estimates for key accrual summaries including the mean and standard deviation of the accrual period.

Conclusion

The accrual period of a clinical trial should be carefully considered, and the allocation of sufficient time for participant recruitment is a fundamental aspect of planning a clinical trial.
Internal fixation of femoral shaft fractures in children by intramedullary Kirschner wires (a prospective study): its significance for developing countries
Authors: Chitgopkar Shashank D
Published: March 2005

Background

To evaluate internal fixation by intramedullary Kirschner wires as a surgical technique in the treatment of femoral shaft fractures in children by a prospective study.

Methods

17 femoral shaft fractures at various levels in 16 children aged 2–15 years were treated by closed intramedullary Kirschner wiring under image intensifier control between May 2000 and October 2003. No external splint was used.

Results

Fracture union was achieved in 6–14 weeks. Non-weight bearing crutch walking was started 2–3 days after surgery. Full weight bearing started 6–14 weeks. Average operative time was 40 min (range 20–72 min). Wires were removed after 8–22 weeks. There were no infections, no limb length disparity. One child had pin track ulceration. A big child of 14 years had angulation of the fracture.

Conclusion

Intramedullary nailing of femoral shaft fractures in children by stainless steel Kirschner wires is an effective method, which compares well with other studies. It is a simple procedure, which can be easily reproduced. Blood loss is minimal, and the operative time short. There is no need pre-bend the wires in a C or S curve. Stainless steel Kirschner wires are cheap, universally available, and can be manufactured locally. The cost of Image intensifiers is affordable in most of the cities of the developing countries. The hospital does not have to maintain a costly inventory. Provides early mobility, return to home and, school. Gives a predictable clinical pathway and reduces occupancy of hospital beds.

The technique was successfully applied for internal fixation of other diaphyseal fractures in children and some selected diaphyseal fractures in adults. Based on my experience and a review of the literature, I recommend this technique as a modality for treatment of femoral shaft fractures in children aged 2 to 14 years.
An ethical framework for cardiac report cards: a qualitative study
Authors: Richard Shawn A , Rawal Shail , Martin Douglas K
Published: March 2005

Background

The recent proliferation of health care report cards, especially in cardiac care, has occurred in the absence of an ethical framework to guide in their development and implementation. An ethical framework is a consistent and comprehensive theoretical foundation in ethics, and is formed by integrating ethical theories, relevant literature, and other critical information (such as the views of stakeholders). An ethical framework in the context of cardiac care provides guidance for developing cardiac report cards (CRCs) that are relevant and legitimate to all stakeholders. The purpose of this study is to develop an ethical framework for CRCs.

Methods

Delphi technique – 13 panelists: 2 administrators, 2 cardiac nurses, 5 cardiac patients, 2 cardiologists, 1 member of the media, and 1 outcomes researcher. Panelists' views regarding the ethics of CRCs were analyzed and organized into themes.

Results

We have organized panelists' views into ten principles that emerged from the data: 1) improving quality of care, 2) informed understanding, 3) public accountability, 4) transparency, 5) equity, 6) access to information 7) quality of information, 8) multi-stakeholder collaboration, 9) legitimacy, and 10) evaluation and continuous quality improvement.

Conclusion

We have developed a framework to guide the development and dissemination of CRCs. This ethical framework can provide necessary guidance for those generating CRCs and may help them avoid a number of difficult issues associated with existing ones.
Amplifier spurious input current components in electrode-electrolyte interface impedance measurements
Authors: Felice Carmelo J , Madrid Rossana E , Valentinuzzi Max E
Published: March 2005

Background

In Impedance Microbiology, the time during which the measuring equipment is connected to the bipolar cells is rather long, usually between 6 to 24 hrs for microorganisms with duplication times in the order of less than one hour and concentrations ranging from 101 to 107 [CFU/ml]. Under these conditions, the electrode-electrolyte interface impedance may show a slow drift of about 2%/hr. By and large, growth curves superimposed on such drift do not stabilize, are less reproducible, and keep on distorting all over the measurement of the temporal reactive or resistive records due to interface changes, in turn originated in bacterial activity. This problem has been found when growth curves were obtained by means of impedance analyzers or with impedance bridges using different types of operational amplifiers.

Methods

Suspecting that the input circuitry was the culprit of the deleterious effect, we used for that matter (a) ultra-low bias current amplifiers, (b) isolating relays for the selection of cells, and (c) a shorter connection time, so that the relays were maintained opened after the readings, to bring down such spurious drift to a negligible value. Bacterial growth curves were obtained in order to test their quality.

Results

It was demonstrated that the drift decreases ten fold when the circuit remained connected to the cell for a short time between measurements, so that the distortion became truly negligible. Improvement due to better-input amplifiers was not as good as by reducing the connection time. Moreover, temperature effects were insignificant with a regulation of ± 0.2 [°C]. Frequency did not influence either.

Conclusion

The drift originated either at the dc input bias offset current (Ios) of the integrated circuits, or in discrete transistors connected directly to the electrodes immersed in the cells, depending on the particular circuit arrangement. Reduction of the connection time was the best countermeasure.
Ocean climate and seal condition
Authors: Le Boeuf Burney J , Crocker Daniel E
Published: March 2005

Background

The condition of many marine mammals varies with fluctuations in productivity and food supply in the ocean basin where they forage. Prey is impacted by physical environmental variables such as cyclic warming trends. The weaning weight of northern elephant seal pups, Mirounga angustirostris, being closely linked to maternal condition, indirectly reflects prey availability and foraging success of pregnant females in deep waters of the northeastern Pacific. The aim of this study was to examine the effect of ocean climate on foraging success in this deep-diving marine mammal over the course of three decades, using cohort weaning weight as the principal metric of successful resource accrual.

Results

The mean annual weaning weight of pups declined from 1975 to the late 1990s, a period characterized by a large-scale, basin-wide warm decadal regime that included multiple strong or long-duration El Niños; and increased with a return to a cool decadal regime from about 1999 to 2004. Increased foraging effort and decreased mass gain of adult females, indicative of reduced foraging success and nutritional stress, were associated with high ocean temperatures.

Conclusion

Despite ranging widely and foraging deeply in cold waters beyond coastal thermoclines in the northeastern Pacific, elephant seals are impacted significantly by ocean thermal dynamics. Ocean warming redistributes prey decreasing foraging success of females, which in turn leads to lower weaning mass of pups. Annual fluctuations in weaning mass, in turn, reflect the foraging success of females during the year prior to giving birth and signals changes in ocean temperature cycles.
Lupus erythematosus proliferative glomerulonephritis in fetus
Authors: Daïkha-Dahmane F , Bault J P , Molina-Gomes D , Hillion D , Ville Y
Published: March 2005

We report the case of a fetus with proliferative glomerulonephritis in the context of maternal systemic lupus erythematosus (SLE). The pattern of the renal lesions correspond to the class III of revisited WHO classification of glomerulonephritis in SLE. Amniotic fluid analysis showed a high level of albumin and the presence of anti-Ro and anti-DNA antibodies that were possibly responsible for the renal injury.
Hyperacute renal failure as the initial presentation of systemic lupus erythematosus
Authors: Arbel O , Pizov G , Ben-Yehuda A , Rubinow A , Naparstek Y , Amital H
Published: March 2005

SLE nephritis is usually a slow process that may lead to renal failure many years after its first presentation. Success of different therapeutic modalities in preventing renal failure is therefore evaluated and compared only after many years of treatment. Lately, this conservative philosophy has been challenged with the acknowledgment of collapsing glomerulopathy (CG), a recent recognized clinical-pathological entity, characterized by rapidly progressive renal failure. Despite this ominous description we present an unusual case of a patient who presented with systemic lupus erythematosus (SLE) and clinical and pathological findings of CG, who completely remitted several weeks after commencing immunosuppressive therapy with intravenous cyclophosphamide and prednisolone.
The dietary supplement ephedrine induces b-adrenergic mediated exacerbation of systemic lupus erythematosus in NZM391 mice
Authors: Hudson C A , Mondal T K , Cao L , Kasten-Jolly J , Huber V C , Lawrence D A
Published: March 2005

The dietary supplement and adrenergic receptor agonist ephedrine has been a controversial topic as its safety has been questioned. b-adrenergic receptor (b-AR) activation causes immunomodulation, which may contribute to promotion of autoimmune pathology. This report investigated the ability of ephedrine to exacerbate processes associated with autoimmune disease in a lupus-prone mouse model. To mimic human supplementation, ephedrine was administered to NZM391 (lupus-prone) and BALB/c (nonlupus prone) mice orally twice a day for three months at a dose of 50 and 100 mg/day. Some ephedrine-treated NZM391 mice also were preadministered the b-AR antagonist propranolol to investigate b-AR involvement. Mice were bled monthly, and sera were assayed for a variety of lupus manifestations and immunological measurements. In NZM391 males and females, both doses of ephedrine significantly increased lupus manifestations, including IgG production and organ-directed autoantibody titers, and significantly lowered the ratio of IgG2a/IgG1 compared to controls. Ephedrine significantly decreased female lifespan and significantly increased circulating populations of plasma cells (CD38hi CD19lo cytoplasmic IgG+) and CD40+ B1a cells, while preventing an age-related decrease in the B1a cell population expressing a high level of CD5. While ephedrine induced gender-specific immunomodulation in BALB/c mice, increases in the lupus manifestations of anti-dsDNA titers and serum urea nitrogen were not detected. Preadministration of propranolol decreased lupus manifestations and serum levels of IgG and IgE in ephedrine-treated mice, but did not block the shift towards IgG1 production. These findings indicate that ephedrine via b-AR can exacerbate lupus symptoms in NZM391 mice and that blockade of the b-ARs on B cells, and not T cells, apparently was of greater importance as the inhibition of lupus symptoms corresponded to an inhibition of immunoglobulin levels, not a change of Th1/Th2 balance.
Long-term outcome of patients with diffuse proliferative lupus nephritis treated with prednisolone and oral cyclophosphamide followed by azathioprine
Authors: Chan T M , Tse K C , Tang C SO , Lai K N , Li F K
Published: March 2005

The short-term outcome of patients with diffuse proliferative lupus nephritis (DPLN) has improved with advances in immunosuppressive treatment. However, the impact of different immunosuppressive regimens on long-term renal function remains to be defined.

This prospective cohort study examined the long-term renal function and disease relapse in adults with biopsy-proven DPLN, significant proteinuria, and hypoalbuminemia, who had been treated with sequential immunosuppression comprising prednisolone and oral cyclophosphamide as induction followed by low-dose prednisolone and azathioprine as maintenance.

Sixty-six patients with 68 episodes of DPLN were included, with follow-up of 91.7 + 36.7 months. 82.4% achieved complete remission and 39.1% relapsed during follow-up. Patients in partial remission were at higher risk of relapse compared with those in complete remission (hazard ratio 6.2, P, 0.001). Serum creatinine remained stable over time (P = 0.931), while creatinine clearance showed a significant increase with time after treatment (P = 0.032). Three (4.4%) patients had doubling of baseline creatinine, but none reached end-stage renal failure or died. Univariate and mixed model analyses showed that the evolution of long-term renal function was significantly influenced by the chronicity score and creatinine clearance at baseline, and by the renal function at one year after treatment.

These data demonstrate the efficacy of sequential immunosuppression in preserving renal function in most Chinese subjects with DPLN. The results also indicate that irreversible renal scarring (as reflected by baseline chronicity score), renal reserve (as reflected by renal function at baseline and one year), and an induction regimen that is effective in preserving the nephron mass are critical determinants of long-term renal outcome.
Autoimmune rheumatic diseases in the intensive care unit: experience from a tertiary referral hospital and review of the literature
Authors: Camargo J F , Tobón G J , Fonseca N , Diaz J L , Uribe M , Molina F , Anaya J-M
Published: March 2005

Autoimmune rheumatic diseases (AIRD) are not uncommon in the general population and up to one third of hospitalized patients with AIRD may need admission to intensive care unit (ICU). This paper describes the causes of admission, the clinical features and outcome of 24 AIRD patients admitted to a medical ICU from a third level hospital. Thirteen patients had systemic lupus erythematosus (54.2%), three rheumatoid arthritis (12.5%), three pulmonary renal syndrome (12.5%), two dermatopolymyositis (8.3%), two scleroderma (8.3%) and one antiphospholipid syndrome (4.2%). The main causes for ICU admission were rheumatic disease flare-up (37.5%), infection (37.5%) and complications derived from rheumatic disease (29.1%). Mortality during ICU stay was 16.7% (four patients). Excluding shock requiring vasopressor support, no statistical difference was found between survivors and nonsurvivors; although there was a trend to higher test severity scores (APACHE II, ODIN) in nonsurvivors. Our results reveal a lower mortality rate in AIRD patients admitted to the ICU than reported previously. Severity scores such as APACHE II are predictors of mortality in patients with AIRD in the ICU.
Phase II Study of Efficacy, Safety, and Pharmacokinetics of Trastuzumab Monotherapy Administered on a 3-Weekly Schedule
Authors: Baselga José , Carbonell Xavier , Castañeda-Soto Noel-Jaime , Clemens Michael , Green Michael , Harvey Vernon , Morales Serafin , Barton Claire , Ghahramani Parviz
Published: March 2005

Purpose

This phase II study investigated the efficacy, safety, and pharmacokinetics of trastuzumab monotherapy given as first-line treatment once every 3 weeks (3-weekly) in women with human epidermal growth factor receptor 2 (HER2) -positive metastatic breast cancer (MBC).

Patients and Methods

Patients with previously untreated HER2-positive MBC received a loading dose of trastuzumab, 8 mg/kg intravenously (IV) and then 6 mg/kg IV at 3-week intervals until disease progression or patient withdrawal.

Results

In total, 105 patients received a median of five cycles of therapy (range, 1 to 35+). The overall response rate was 19% (23% in patients with measurable centrally confirmed immunohistochemistry [IHC] 3+ and/or fluorescence in situ hybridization [FISH] -positive disease) and clinical benefit rate (complete and partial responses plus stable disease for at least 6 months) was 33% (36% in patients with measurable centrally confirmed IHC 3+ and/or FISH-positive disease). Median time to progression was 3.4 months (range, 0.6 to 23.6 months). The most common treatment-related adverse events were rigors, pyrexia, headache, nausea, and fatigue. Median baseline left ventricular ejection fraction was 63%; this did not significantly change over the course of the study. The average exposure to trastuzumab observed in this study was similar to that in previous studies of the weekly regimen. However, as expected, mean trough trastuzumab concentrations were lower and peak levels were higher with 3-weekly trastuzumab compared with weekly treatments.

Conclusion

Administering higher doses on a 3-weekly schedule did not compromise the efficacy and safety of trastuzumab in women with HER2-positive MBC, and average exposure was similar to that observed with weekly therapy. Three-weekly trastuzumab may represent a convenient alternative to weekly administration.
Extracapsular Extension of Pelvic Lymph Node Metastases From Urothelial Carcinoma of the Bladder Is an Independent Prognostic Factor
Authors: Fleischmann Achim , Thalmann George N. , Markwalder Regula , Studer Urs E.
Published: March 2005

Purpose

To analyze the prognostic impact of risk factors for urothelial carcinoma of the bladder (UCB) with pelvic lymph node (LN) metastases.

Patients and Methods

We analyzed a consecutive series of 507 patients with UCB who were preoperatively staged N0M0. One hundred one of 124 eligible patients who were treated with radical cystectomy and standardized extended bilateral pelvic lymphadenectomy with curative intent and had postoperatively confirmed LN metastases were evaluated in regard to recurrence-free and overall survival.

Results

A median of 22 nodes per patient (range, 10 to 43 nodes) were removed and examined. Median recurrence-free and overall survival durations were 17 months and 21 months (range for both, 1 to 191 months), respectively. In the multivariate analysis for recurrence-free survival, extracapsular extension of LN metastases was the strongest prognostic factor (P = .019). Other variables such as tumor stage (pT1/2 v pT3 and pT4), the number (< five v ≥ five), and the percentage (< 20% v ≥ 20%) of metastatic nodes had a significant influence on recurrence-free and overall survival in the univariate analysis. However, they all failed to be significant prognostic factors in the multivariate analysis.

Conclusion

The results of this study indicate that radical cystectomy with bilateral lymphadenectomy can have a curative effect in a subset of patients with pelvic LN positive UCB. Provided that a representative number of LNs are removed by meticulous lymphadenectomy and that a thorough histologic examination is performed, prognosis for such patients can be determined quite reliably. In the multivariate analysis, extracapsular extension of LN metastases was the strongest factor predicting prognosis.
Possible Future Issues in the Treatment of Glioblastomas: Special Emphasis on Cell Migration and the Resistance of Migrating Glioblastoma Cells to Apoptosis
Authors: Lefranc Florence , Brotchi Jacques , Kiss Robert
Published: March 2005

Purpose

The present review aims to emphasize that malignant gliomas are characterized by the diffuse invasion of distant brain tissue by a myriad of single migrating cells that exhibit decreased levels of apoptosis (programmed cell death type I), thus a resistance to cytotoxic insult.

Methods

The present review surveys the molecular mechanisms of migration in malignant gliomas and potential issues arising from treatments, in addition to relationships between glioma cell migration and resistance to apoptosis in terms of the molecular signaling pathways.

Results

Clinical and experimental data demonstrate that glioma cell migration is a complex combination of multiple molecular processes, including the alteration of tumor cell adhesion to a modified extracellular matrix, the secretion of proteases by the cells, and modifications to the actin cytoskeleton. Intracellular signaling pathways involved in the acquisition of resistance to apoptosis by migrating glioma cells concern PI3K, Akt, mTOR, NF-κB, and autophagy (programmed cell death type II).

Conclusion

A number of signaling pathways can be constitutively activated in migrating glioma cells, thus rendering these cells resistant to cytotoxic insults. However, these pathways are not all constitutively activated at the same time in any one glioma. Particular inhibitors should therefore only be chosen if the target is present in the tumor tissue, but this is only possible if individual patients are submitted to the molecular profiling of their tumors before undergoing any treatment to combat their migratory glioma cells. Specific antimigratory compounds should be added to conventional radio- and/or chemotherapy.
Efficacy of Prophylactic Mastectomy in Women With Unilateral Breast Cancer: A Cancer Research Network Project
Authors: Herrinton Lisa J. , Barlow William E. , Yu Onchee , Geiger Ann M. , Elmore Joann G. , Barton Mary B. , Harris Emily L. , Rolnick Sharon , Pardee Roy , Husson Gail , Macedo Ana , Fletcher Suzanne W.
Published: March 2005

Purpose

We investigated the efficacy of contralateral prophylactic mastectomy (CPM) in reducing contralateral breast cancer incidence and breast cancer mortality among women who have already been diagnosed with breast cancer.

Methods

This retrospective cohort study comprised approximately 50,000 women who were diagnosed with unilateral breast cancer during 1979 to 1999. Using computerized data confirmed by chart review, we identified 1,072 women (1.9%) who had CPM. We obtained covariate information for these women and for a sample of 317 women who did not undergo CPM.

Results

The median time from initial breast cancer diagnosis to the end of follow-up was 5.7 years. Contralateral breast cancer developed in 0.5% of women with CPM, metastatic disease developed in 10.5%, and subsequent breast cancer developed in 12.4%; 8.1% died from breast cancer. Contralateral breast cancer developed in 2.7% of women without CPM, and 11.7% died of breast cancer. After adjustment for initial breast cancer characteristics, treatment, and breast cancer risk factors, the hazard ratio (HR) for the occurrence of contralateral breast cancer after CPM was 0.03 (95% CI, 0.006 to 0.13). After adjustment for breast cancer characteristics and treatment, the HRs for the relationship of CPM with death from breast cancer, with death from other causes, and with all-cause mortality were 0.57 (95% CI, 0.45 to 0.72), 0.78 (95% CI, 0.57 to 1.06), and 0.60 (95% CI, 0.50 to 0.72), respectively.

Conclusion

CPM seems to protect against the development of contralateral breast cancer, and although women who underwent CPM had relatively low all-cause mortality, CPM also was associated with decreased breast cancer mortality.
Combining Gemcitabine and Capecitabine in Patients With Advanced Biliary Cancer: A Phase II Trial
Authors: Knox Jennifer J. , Hedley David , Oza Amit , Feld Ron , Siu Lillian L. , Chen Eric , Nematollahi Mahsan , Pond Gregory R. , Zhang Jessica , Moore Malcolm J.
Published: March 2005

Purpose

Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer.

Patients and Methods

Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m2 orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m2 intravenously over 30 minutes on days 1 and 8.

Results

Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment.

Conclusion

The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points.
Terpinen-4-ol: mechanisms of relaxation on rabbit duodenum
Authors: Nascimento Nilberto R F , Leal-Cardoso José H , Lessa Lucília M A , Roriz-Filho Jarbas S , Cunha Karina M A , Fonteles Manassés C
Published: March 2005

The effect of terpinen-4-ol was studied on rabbit duodenum in-vitro. Terpinen-4-ol induced relaxation of the basal tonus (IC50 170.2 (95% confidence interval, 175–204) μm) with a maximal relaxant response of 180.4 ± 3.9% (n = 6) of the contraction induced by 60 mm [K+]. The maximal relaxation induced in control conditions was not affected (P>0.05) by pretreatment of the tissues with phentolamine (50 μm) or propranolol (10 μm), Ng nitro-l-arginine methyl ester (L-NAME; 1 mm), 1H-(1,2,4)-oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 100 μm), hexamethonium (1 mm), tetrodotoxin (1 μm), the mixture charybdotoxin-apamin (1 μm), glibenclamide (10 μm), 4-aminopyridine (10 μm) or tetraethylammonium (100 μm). In addition, terpinen-4-ol completely relaxed tissues precontracted with 60 mm [K+] solutions (IC50 325.9 (245.1–433.1) μm) and also blocked (IC50 154.7 (117.7–191.7) μm) the phasic component of this contraction. At a concentration of 195 and 650 μm it reduced by 41.3 ± 3.4% and 75.4 ± 3.1%, respectively the maximal contractile response to Ca2+ in depolarized duodenum. Terpinen-4-ol completely blocked the component of carbachol-induced contraction, which was resistent to nifedipine (100 μm) pretreatment or to a Ca2+-free solution. These data show that terpinen-4-ol relaxes intestinal smooth muscle and suggest that this effect is myogenic in nature and depends on calcium antagonism.
Effect of enzyme inducers and inhibitors on the pharmacokinetics of oltipraz in rats
Authors: Bae Soo Kyung , Lee Shin Jung , Kim Young Hoon , Kim Taekrho , Lee Myung Gull
Published: March 2005

A series of in-vitro and in-vivo experiments, using various inducers and inhibitors of hepatic microsomal cytochrome P450 (CYP) isozymes, was conducted to study oltipraz pharmacokinetics in rats. In in-vivo studies, oltipraz at a dose of 10 mg kg−1 was administered intravenously to rats. In rats pretreated with SKF 525-A (a nonspecific CYP isozyme inhibitor in rats; n = 9), the time-averaged total body clearance (CL) of oltipraz was significantly slower (56.6% decrease) than that in untreated rats (n = 9). This indicated that oltipraz is metabolized via CYP isozymes in rats. Hence, various enzyme inducers or inhibitors were used in in-vitro and in-vivo studies in rats. In rats pretreated with 3-methylcholanthrene (n = 9 and 8 for untreated and treated groups, respectively), phenobarbital (n = 7 and 10 for untreated and treated groups, respectively) or dexamethasone (n = 7 and 12 for untreated and treated groups, respectively) (main inducers of CYP1A1/2, 2B1/2 and 3A1/2 in rats, respectively), the CL values were significantly faster (38.4, 94.4 and 33.6% increase, respectively). In rats pretreated with sulfaphenazole (n = 8 and 9 for untreated and treated groups, respectively), quinine (n = 7 and 9 for untreated and treated groups, respectively) or troleandomycin (n = 8 and 9 for untreated and treated groups, respectively) (main inhibitors of CYP2C11, 2D1 and 3A1/2 in rats, respectively), the CL values were significantly slower (31.0, 27.6 and 36.3% decrease, respectively). The in-vivo results with various enzyme inhibitors correlated well with the in-vitro intrinsic clearance for disappearance of oltipraz (CLint) (n = 5, each). The above data suggested that oltipraz could be metabolized in male rats mainly via CYP1A1/2, 2B1/2, 2C11, 3A1/2 and 2D1.
Dermal delivery of desmopressin acetate using colloidal carrier systems
Authors: Getie Melkamu , Wohlrab Johannes , Neubert Reinhard H H
Published: March 2005

Recently, the transdermal route has received attention as a promising means to enhance the delivery of drug molecules, particularly peptides, across the skin. In this work, the skin penetration profiles of desmopressin acetate from a colloidal system (water-in-oil microemulsion) and an amphiphilic cream, a standard formulation, were determined using Franz diffusion cells and compared. In the case of the microemulsion, the total percentages of dose obtained from different skin layers (stratum corneum to subcutaneous tissue) were 3.30 ± 0.67, 7.37 ± 2.43 and 15.54 ± 2.72 at 30, 100 and 300 min, respectively. Similarly, 5.19 ± 0.96, 8.04 ± 0.97 and 14.4 ± 5.15% of the dose applied was extracted from the skin treated with the cream. About 6% of the applied dose reached the acceptor compartment from the microemulsion instead of 2% from the cream within 300 min. The concentration of drug that penetrated into the upper layers of the skin was higher from the cream than from the microemulsion at all time intervals. On the other hand, a higher amount of drug was found in the deeper skin layers and in the acceptor compartment from the microemulsion.
Hydroquinone modulates reactivity of peroxynitrite and nitric oxide production
Authors: Kim Ae Ra , Cho Jae Youl , Lee Ji Yeon , Choi Jae Sue , Chung Hae Young
Published: March 2005

Peroxynitrite (ONOO−), a potent cytotoxic oxidant formed by the reaction of nitric oxide (*NO) and superoxide radical (*O2−), may be rapidly lethal in a cellular milieu due to oxidization and nitration processes. In the present study, hydroquinone displayed strong ONOO− scavenging activity and inhibitory effect on NO production in murine macrophage RAW264.7 cells. Hydroquinone strongly scavenged ONOO− induced dihydrorhodamine 123 oxidation in a dose-dependent manner compared with other reactive species such as *O2− and *NO. Hydroquinone also decreased levels of ONOO− induced nitrotyrosine of glutathione reductase and consequently prevented the enzyme from ONOO− induced damage. Furthermore, hydroquinone suppressed NO production, a cellular pathway for ONOO− formation, in lipopolysaccharide-activated RAW264.7 cells via inhibition of inducible NO synthase expression. The inhibitory effect by hydroquinone seems to be mediated by interruption of lipopolysaccharide-induced signalling such as activation of nuclear factor-kB and extracellular signal-related kinases 1 and 2. The results suggest that hydroquinone may potently modulate reactivity of ONOO− and may therefore be a useful agent against ONOO− mediated diseases.
Nicardipine, a calcium antagonist, does not aggravate intracerebral haemorrhage in an intracerebral haemorrhage model in rats
Authors: Suzuki Masanori , Hayashi Aska , Sasamata Masao
Published: March 2005

Despite controversy over their safety in patients with intracerebral haemorrhage, calcium antagonists are widely used in the treatment of hypertensive emergencies. Here, we investigated the effects of nicardipine on haematoma size and neurological deficit in a rat model of collagenase-induced intracerebral haemorrhage. Injection of collagenase (0.014 U) into the striatum induced haematoma (19.9 ± 3.4 mm3) in the striatum and brain oedema. Drugs were infused from 30 min after collagenase injection for 3 h under conscious conditions. Nicardipine intravenously at 0.1, 1 and 10 μg kg−1 min−1 affected neither haematoma size nor the degree of brain oedema. Nicardipine at these doses provided a stable and dose-dependent decrease in mean blood pressure of 6%, 13% and 33%, respectively, with an increase in heart rate that was apparently caused reflexively. Further, nicardipine did not aggravate the neurological deficits in these intracerebral haemorrhage rats, primarily forearm flexion behaviour on suspension by the tail and circling behaviour. These results indicate that nicardipine infusion stably decreased blood pressure without affecting intracerebral haemorrhage in an intracerebral haemorrhage model in rats.
High-speed digital imaging method for ciliary beat frequency measurement
Authors: Dimova Svetlana , Maes Frederik , Brewster Marcus E , Jorissen Mark , Noppe Mark , Augustijns Patrick
Published: March 2005

The aim of this study was to develop a high-speed digital imaging system and related software for ciliary beat frequency (CFB) analysis in order to establish an automated and reliable method that is observer independent and faster compared to the conventional computerized microscope photometry method. Using primary human nasal epithelial cell cultures, the CBF was recorded with a computerized microscope photometry system and a high-speed digital imaging system. To obtain a wide range of frequencies, glycocholate (0.5%) and chlorocresol (0.005%) were used as ciliostimulatory and cilio-inhibitory reference compounds, respectively. The mean values in hertz (± s.d.) obtained with the photometry and high-speed digital imaging systems were: controls 8.2 ± 0.9 and 7.9 ± 1.1; chlorocresol 5.0 ± 0.9 and 5.1 ± 1.1; glycocholate 9.8 ± 1.0 and 9.7 ± 0.8. A similar increase (by 20 and 24%) and decrease (by 38 and 35%) in CBF was determined by the two methods after glycocholate and chlorocresol treatment, respectively. The mean difference between the photometry and high-speed digital imaging methods was 0.2 ± 0.6 Hz, and the Bland-Altman limits of agreement were from −1.0 to + 1.4 Hz, suggesting that the results obtained by these two methods could be used interchangeably. These results show the reliability of the high-speed digital imaging system and the software developed for in-vitro CBF measurements. The advantages of the system include: (i) fast data acquisition and calculation, (ii) whole field automated CBF analysis and (iii) reduction in selection bias.
Investigation of oral bioavailability and brain distribution of the Ind(8)-Val conjugate of indinavir in rodents
Authors: de Oliveira Manuela Pereira , Olivier Jean-Christophe , Pariat Claudine , Roche Dominique , Greiner Jacques , Vierling Pierre , Couet William
Published: March 2005

Protease inhibitors are successfully used for the treatment of acquired immune deficiency syndrome (AIDS) although their biopharmaceutical characteristics are not optimal. Prodrugs have therefore been synthesized to increase protease inhibitor bioavailability and brain distribution. Among several compounds tested, a valine derivative of indinavir (Ind(8)-Val) showed promising characteristics using an in-vitro Caco-2 cell model. The objective of this study was to further investigate this compound using in-situ and in-vivo approaches. The pharmacokinetics of indinavir (Ind) and Ind(8)-Val were investigated in rats after intravenous and oral administration. Free indinavir resulting from in-vivo hydrolysis of Ind(8)-Val could not be detected in the plasma of rats receiving Ind(8)-Val. Furthermore Ind(8)-Val bioavailability was only 32% on average compared with 76% for indinavir, and effective permeability coefficients determined with a single-pass intestinal perfusion method were close to 25 times 106 cms−1 for the two compounds. Brain-to-plasma concentration ratios in the post equilibrium phase after intravenous administration to mice were 9.7 ± 8.1% for indinavir and 2.5 ± 2.7% for Ind(8)-Val. In conclusion, the promising biopharmaceutical characteristics of Ind(8)-Val suggested from previous in-vitro experiments with the Caco-2 cell model were not confirmed by in-situ and in-vivo experiments.
Influence of magnesium aluminium silicate on rheological, release and permeation characteristics of diclofenac sodium aqueous gels in-vitro
Authors: Pongjanyakul Thaned , Priprem Aroonsri , Puttipipatkhachorn Satit
Published: March 2005

The effect of magnesium aluminium silicate (MAS) on rheological, release and permeation characteristics of diclofenac sodium (DS) aqueous gels was investigated. DS aqueous gels were prepared using various gelling agents, such as 15% w/w poloxamer 407 (PM407), 1% w/w hydroxypropylmethylcellulose (HPMC), and 1% w/w high and low viscosity grades of sodium alginate (HV-SA and LV-SA, respectively). Different amounts of MAS (0.5, 1.0 and 1.5% w/w) were incorporated into the DS gels. Incorporation of MAS into the DS gels prepared using SA or PM407 caused a statistical increase in viscosity (P<0.05) and a shift from Newtonian flow to pseudoplastic flow with thixotropic property. The DS release rates of these composite gels were significantly decreased (P<0.05) when compared with the control gels. This was due to an interaction between MAS and PM407 or SA, and adsorption of DS onto MAS particles. Moreover, a longer lag time and no change in DS permeation flux were found when MAS was added to the gels. The findings suggest that the rheological characteristics of gels prepared using PM407 or SA could be improved by incorporating MAS. However, the use of MAS could retard the DS release and extend the lag time of DS permeation.
Development of simple thiol-reactive liposome formulations, one-step analysis and physicochemical characterization
Authors: Kaourma E , Hatziantoniou S , Georgopoulos A , Kolocouris A , Demetzos C
Published: March 2005

The aim of this study was to synthesize simple thiol-reactive conjugates from maleimide and lipoamines (stearylamine or oleylamine) and to develop a simple, fast and low-cost method for the preparation of lyophilized general-purpose thiol-reactive liposomes. A formulation of egg phosphatidylcholine-dipalmitoylphoshatidylglycerol (9:0.1 molar ratio) was developed and characterized. Freeze-drying methodology was established to produce a stock of liposomes and the physicochemical characteristics of the reconstituted liposomes were compared with those of the initial preparation. The physicochemical properties (size and ζ-potential) of the new liposomal formulations were studied. High-performance thin-layer chromatography coupled to a flame ionization detector was applied for one-step analysis of the liposomal components and for determining the maleimide-lipoamine conjugates phospholipid molar ratio. The differences concerning the incorporation efficiency of the synthetic conjugates into liposomes were discussed on the basis of their conformational properties. The small difference in structure between the two thiol-reactive conjugates (i.e., the C18 alkyl chain double bond) causes a considerable difference in phospholipids packing of the resulting lipidic bilayers of the liposomes; the conformational bending of conjugate maleimide-oleylamine may contribute to the final architecture of liposomes.
Clinical Features of Aneurysms of the Posterior Cerebral Artery: A 15-year Experience with 21 Cases
Authors: Hamada Jun-ichiro , Morioka Motohiro , Yano Shigetoshi , Todaka Tatemi , Kai Yutaka , Kuratsu Jun-ichi
Published: March 2005

OBJECTIVE:

To investigate the characteristic clinical behavior and develop guidelines for the clinical management of posterior cerebral artery aneurysms, we reviewed 21 cases treated during a 15-year period.

METHODS:

Between 1988 and 2002, we treated 21 patients (10 male, 11 female; mean age, 49.8 yr) with posterior cerebral artery aneurysms at Kumamoto University Hospital and its affiliated hospitals. Data relating to the clinical, radiological, and surgical approaches were analyzed.

RESULTS:

There were 20 saccular aneurysms, 6 of which were giant or large aneurysms, and 1 dissecting aneurysm. Of the 21 patients, 15 presented with subarachnoid hemorrhage; in 3 patients, an unruptured saccular aneurysm was found incidentally during an evaluation for other cerebral pathological conditions. Two patients presented with progressive homonymous hemianopsia because of the mass effect of the aneurysm, and 1 patient experienced the sudden onset of homonymous hemianopsia because of thrombosis of the aneurysm and afferent artery. Open or endovascular surgery was performed in 19 patients: 14 made a good recovery, 2 had a moderate disability because of angiospasm or infarction after aneurysm trapping, 1 had a severe disability because of angiospasm and cerebral contusion, and 2 died because of severe angiospasm. Of 2 conservatively treated patients, 1 made a good recovery but the other died as a result of rebleeding.

CONCLUSION:

Posterior cerebral artery aneurysms have specific clinical characteristics compared with aneurysms located elsewhere. The aneurysmal site and size and the surgical technique did not significantly influence treatment outcomes.
Factors Associated with Neurological Outcome and Lesion Progression in Traumatic Subarachnoid Hemorrhage Patients
Authors: Chieregato Arturo , Fainardi Enrico , Morselli-Labate Antonio Maria , Antonelli Vincenzo , Compagnone Christian , Targa Luigi , Kraus Jess , Servadei Franco
Published: March 2005

OBJECTIVE:

Traumatic subarachnoid hemorrhage (tSAH) is a frequent finding after closed-head injuries, and its presence is a powerful factor associated with poor outcome. The exact mechanism linking tSAH and an adverse outcome is poorly understood. The aim of this study was to identify the factors that may predict outcomes and changes in the computed tomographic (CT) scans of lesions in a selected population of tSAH patients.

METHODS:

We evaluated 141 patients admitted consecutively from January 1, 1997, to January 31, 1999, with a CT diagnosis of tSAH. The admission and “worst” CT scans were recorded. CT scan changes were reported as “significant CT progression” (changes in the Marshall classification) or “any CT progression.” The amount of subarachnoid blood was recorded using a modified Fisher classification. Outcome was assessed at 6 months after injury with the Glasgow Outcome Scale.

RESULTS:

Twenty-eight patients (19.9%) had an unfavorable Glasgow Outcome Scale outcome. In the univariate analysis, prognosis was significantly related to age, admission Glasgow Coma Scale score, Marshall CT classification score at admission and on the worst CT scan, amount of tSAH, and volume of the associated brain contusions. From multivariate analysis, the only factors independently related to outcome were the Glasgow Coma Scale score (P < 0.01) and size of the tSAH at admission (P < 0.001). Thirty-four patients (24.1%) had significant CT lesion progression, and 66 patients (46.8%) had some lesion progression. Patients having significant progression of the lesion had a higher risk of an unfavorable outcome (32 versus 10%; P = 0.004). Unadjusted factors predicting CT progression were the Glasgow Coma Scale score at admission, the Marshall classification at admission, the amount of subarachnoid blood, and the presence or volume of associated brain contusions at admission. Independent factors associated with significant CT progression were the amount of tSAH (P < 0.001) and the presence or volume of brain contusions at admission (P < 0.001).

CONCLUSION:

The outcome of patients with tSAH at admission is related in a logistic regression analysis to the admission Glasgow Coma Scale score and to the amount of subarachnoid blood. These patients also have a significant risk of CT progression. The amount of subarachnoid blood and the presence of associated parenchymal damage are powerful independent factors associated with CT progression, thus linking poor outcomes and CT changes.