bluuebunny/crossref_metadata_2025 huggingface dataset:
A matrix‐assisted laser desorption/ionization mass spectrometry study of the non‐enzymatic glycation products of human globins in diabetes
Authors: Lapolla A. , Tubaro M. , Fedele D. , Reitano R. , Aricò N. C. , Ragazzi E. , Seraglia R. , Vogliardi S. , Traldi P.
Published: January 2005

The molecular species present in globins from healthy and diabetic subjects with and without chronic complications have been analyzed by matrix‐assisted laser desorption/ionization mass spectrometry. The technique demonstrated the presence of glycated and glyco‐oxidated species of both α‐ and β‐globins. Their abundances show a good linear relationship with respect to HbA1c values and with the mean daily plasma glucose levels over the 6 weeks preceding the investigation. Interestingly, slightly different behaviour is observed in the data from patients with and without chronic complications; the plots of HbA1c vs. the abundance of glycated and glyco‐oxidated species show different slopes and different intercepts with the y‐axis. To investigate this aspect the mean abundances of glyco‐oxidated species from healthy subjects and from diabetic patients with and without complications were calculated. Higher values were found for the two last sets of samples, but no significant difference was found between them. These data could indicate different individual proclivities to oxidation and/or different oxidation kinetics related to behavioural and environmental factors. Copyright © 2004 John Wiley & Sons, Ltd.
A simple method for the characterization and quantification of soy isoflavone metabolites in the serum of MMTV‐Neu mice using high‐performance liquid chromatography/electrospray ionization mass spectrometry with multiple reaction monitoring
Authors: Morandi Sheila , Locati Daniela , Ferrario Francesca , Chiesa Giulia , Arnoldi Anna
Published: January 2005

In a study aimed at elucidation of the possible role of dietary phytoestrogens in the growth of breast cancer, it was necessary to develop a convenient, accurate, and reproducible method for the characterization and quantification of isoflavone metabolites in the serum of MMTV mice that were fed diets containing different amounts of these polyphenols. The analytical method is based on liquid chromatography with mass spectrometry in multiple reaction monitoring mode, using deuterated genistein as internal standard. The identified metabolites were genistein and dihydrodaidzein (DHD); their average concentrations in serum were 0.71 and 0.21 μM, respectively, for animals fed 1.5 mg/day of genistein and 0.7 mg/day of daidzein. This method assured a limit of quantification of 0.04 μM for genistein and 0.08 μM for DHD, and a limit of detection of 0.018 μM for genistein and 0.035 μM for DHD. The coefficient of variation was 8.9% for genistein and lower than 15% for DHD. This study provides the first data indicating the presence of dihydrodaidzein in serum of mice fed diets containing soy proteins. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of inorganic chlorine stable isotopes by continuous flow isotope ratio mass spectrometry
Authors: Shouakar‐Stash Orfan , Drimmie Robert J. , Frape Shaun K.
Published: January 2005

Chlorine stable isotope analyses of inorganic samples were conducted using continuous flow isotope ratio mass spectrometry (CF‐IRMS) coupled with gas chromatography (GC). Inorganic chloride was precipitated in the form of silver chloride (AgCl) by using silver nitrate in a standard methodology. Chlorine stable isotope analysis was carried out on methyl chloride (CH3Cl) after converting AgCl into CH3Cl by reacting it with methyl iodide (CH3I). The reaction between AgCl and CH3I took place in 20 mL size vials. Addition of CH3I was performed in a glove bag under helium flow. An Agilent 6890 gas chromatograph equipped with a CTC Analytics CombiPAL autosampler and a DB‐5MS 60 m column was used to separate CH3Cl from CH3I. This new technique uses samples as small as 0.2 mg of AgCl (1.4 μmol of Cl−). The chlorine stable isotope analysis using continuous flow technology showed excellent precision and accuracy. The internal precision using pure CH3Cl gas is better than ±0.04‰ (±STDV). The external precision using seawater standard is better than ±0.07‰ (±STDV) for n = 12. Moreover, the sample analysis time is much shorter and many more samples can be analyzed in one day than by using the conventional off‐line techniques. Copyright © 2004 John Wiley & Sons, Ltd.
A method for routine quantitation of urinary 8‐hydroxy‐2′‐deoxyguanosine based on solid‐phase extraction and micro‐high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Sabatini Laura , Barbieri Anna , Tosi Marco , Roda Aldo , Violante Francesco Saverio
Published: January 2005

8‐Hydroxy‐2′‐deoxyguanosine (8OHdG), one of the major oxidative DNA lesions induced by radical agents, is commonly used as a biomarker for oxidative stress, nowadays preferably in urine. In the absence of a commercially available internal standard a micro‐high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry (micro‐HPLC/ESI‐MS/MS) method, suitable for routine analysis of 8OHdG in human urine using external calibration, was developed. Evaluation of the matrix effect showed that the method allows highly sensitive and accurate quantitation despite the absence of an internal standard. HPLC analysis was performed using gradient elution at a flow rate of 10 μL min−1 using a capillary reversed‐phase column and an injection volume of 0.5 μL, with detection of 8OHdG in positive multiple reaction monitoring (MRM) mode. The absolute limit of detection was 0.35 fmol using m/z 168 as a quantifier (fragment) ion. A linear (R2 > 0.999) calibration curve in urine was obtained over a range 0.2–10 ng mL−1. This method is about 20 times more sensitive than previously described procedures, and is characterized by high accuracy (mean 90%) and good reproducibility (RSD < 10%). The optimized method was applied to determination of 8OHdG in 18 urinary samples derived from three healthy volunteers. 8OHdG urinary excretion ranged from 3.0–7.9 μg/day, and a large intra‐individual variation was found. This method, which effectively circumvents the need for isotopically labeled 8OHdG (internal standard), is suitable for routine monitoring of exposure to DNA‐damaging factors in a large number of subjects. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of phenolic acids and flavonoids in dandelion (Taraxacum officinale WEB. ex WIGG.) root and herb by high‐performance liquid chromatography/electrospray ionization mass spectrometry
Authors: Schütz Katrin , Kammerer Dietmar R. , Carle Reinhold , Schieber Andreas
Published: January 2005

Phenolic acids and flavonoids were extracted from a dandelion (Taraxacum officinale WEB. ex WIGG.) root and herb juice and characterized by high‐performance liquid chromatography/electrospray ionization mass spectrometry. Among the 43 compounds detected, 5 mono‐ and dicaffeoylquinic acids, 5 tartaric acid derivatives, 8 flavone and 8 flavonol glycosides were characterized based on their UV spectra and their fragmentation patterns in collision‐induced dissociation experiments. The predominant compound was chicoric acid (dicaffeoyltartaric acid). Furthermore, several caffeoylquinic acid isomers were distinguished in dandelion extracts for the first time by their specific mass spectral data. The present study reveals that even more quercetin glycosides were found in dandelion than hitherto assumed. The occurrence of di‐ and triglycosylated flavonoids in particular has not yet been described. This paper marks the first report on HPLC‐DAD/ESI‐MSn investigations of phenolic compounds in dandelion. Copyright © 2004 John Wiley & Sons, Ltd.
Ketosteroid profiling using Girard T derivatives and electrospray ionization tandem mass spectrometry: direct plasma analysis of androstenedione, 17‐hydroxyprogesterone and cortisol
Authors: Johnson David W.
Published: January 2005

A function of concentrations of three ketosteroids, [(androstenedione + 17α‐hydroxyprogesterone)/cortisol], has been shown to provide better discrimination than the concentration of 17α‐hydroxyprogesterone alone, for the diagnosis of the inherited disease congenital adrenal hyperplasia (CAH). A rapid, direct infusion electrospray ionization tandem mass spectrometry (ESI‐MS/MS) method has been developed to measure this ratio in plasma (100 μL). Sensitivity and specificity result from the preparation of mono‐Girard T derivatives. Androstenedione, 17α‐hydroxyprogesterone and cortisol are individually quantitated by isotope dilution. Excellent statistical correlation with radioimmunoassay (RIA) results for the analysis of 17α‐hydroxyprogesterone is demonstrated. The value of the ratio function of the three ketosteroids is 0.01–0.16 for normal controls (n = 26) and 1.83–18.7 for patients with severe CAH (n = 4). Profiles of ketosteroids derivatized with Girard T from the plasma of a child with severe CAH, generated by ESI‐MS/MS analysis, are shown. Neutral loss scans for 29.5 and 59 Da assist in the identification of the ketosteroids. Copyright © 2004 John Wiley & Sons, Ltd.
State of the Art in Burn Treatment
Authors: Atiyeh Bishara S. , Gunn S. William , Hayek Shady N.
Published: January 2005

Optimal treatment of burn victims requires deep understanding of the profound pathophysiological changes occurring locally and systemically after injury. Accurate estimation of burn size and depth, as well as early resuscitation, is essential. Good burn care includes also cleansing, debridement, and prevention of sepsis. Wound healing, is of major importance to the survival and clinical outcome of burn patients. An ideal therapy would not only promote rapid healing but would also act as an antiscarring therapy. The present article is a literature review of the most up‐to‐date modalities applied to burn treatment without overlooking the numerous controversies that still persist.
Gallstone Disease after Extended (D2) Lymph Node Dissection for Gastric Cancer
Authors: Akatsu Tomotaka , Yoshida Masashi , Kubota Tetsuro , Shimazu Motohide , Ueda Masakazu , Otani Yoshihide , Wakabayashi Go , Aiura Koichi , Tanabe Minoru , Furukawa Toshiharu , Saikawa Yoshiro , Kawachi Shigeyuki , Akatsu Yukako , Kitajima Koichiro Kumai Masaki
Published: January 2005

Few studies have reported the incidence and clinical outcomes of gallstone disease after extended (D2) lymph node dissection for gastric cancer. The present study was designed to retrospectively compare limited (D1) and D2 dissections in terms of gallstone formation, presentation of gallstones, and surgery for gallstone disease. A total of 805 Japanese gastric cancer patients (595 male, 210 female) who underwent curative resection with D1 (n = 490) or D2 (n= 315) dissection were retrospectively reviewed. Of those subjects followed for 70.5 ± 44.3 months (range: 2‐196 months), 102 (12.7%) developed gallstones. The incidence of gallstone formation was higher in the D2 group than in the D1 group (17.8% vs. 9.4%, p= 0.001). The interval between gastrectomy and detection of gallstones was shorter in the D2 group than in the Dl group (18.8 ± 11.4 months vs. 29.4 ± 18.3 months, p = 0.002). Of those with gallstones followed for 48.0 ± 28.6 months (range: 1‐158 months), 74 (72.5%) remained asymptomatic, and 15 (14.7%) experienced mild biliary pain. Thirteen patients (12.7%) developed recurrent biliary pain (n = 3) or biliary complications (n = 10; 6 acute cholecystitis, 3 obstructive jaundice, and 1 cholangitis), and required surgical treatment. Surgery was more frequently sought in the D2 group than in the D1 group (19.5% vs. 4.3%, p = 0.033). In conclusion, patients with D2 dissection developed gallstones more frequently and earlier than patients with D1 dissection. Of those with gallstones, patients with D2 dissection required surgery more often than patients with D1 dissection. A closer follow‐up should be mandatory for gallstone disease after D2 dissection, but further studies are needed before generalizations can be made.
Predictive Value of Procalcitonin for the Diagnosis of Bowel Strangulation
Authors: Ayten Refik , Dogru Osman , Camci Cemalettin , Aygen Erhan , Cetinkaya Ziya , Akbulut Handan
Published: January 2005

Intestinal obstruction is responsible for 3% of admissions to hospital emergency surgical departments, but it is difficult to distinguish simple obstruction from strangulation. Simple criteria for this distinction are sought. In this experimental study, procalcitonin, a known marker of bacterial inflammation, was used to detect strangulation. The predictive value of procalcitonin for small bowel strangulation was evaluated. Thirty male New Zealand rabbits (mean weight: 3.0 kg) were divided into three groups. In the first (control) group, only laparatomy was performed. In the second group, simple obstruction was created by ligating a 10‐cm distal ileum segment. In the third group, distal strangulation was created by ligating a 10‐cm distal ileum segment with the mesentery. Blood (1 cc) was taken from the right auricular vein of each animal for measuring the procalcitonin level. In both the control group and the simple obstruction group the procalcitonin levels were normal. In the strangulation group, elevation of procalcitonin was detected after 30 minutes, and the elevation was statistically significant at 120th minute compared with the control and simple obstruction groups. In patients with small bowel obstruction, measurement of procalcitonin levels is easy to perform and can be used in the follow‐up. A more extensive clinical study is needed to evaluate the accuracy of the test as a marker.
Addition of Rectus Sheath Relaxation Incisions to Emergency Midline Laparotomy for Peritonitis to prevent Fascial Dehiscence
Authors: Marwah Sanjay , Marwah Nisha , Singh Mandeep , Kapoor Ajay , Karwasra Rajender Kumar
Published: January 2005

The incidence of fascial dehiscence and incisional hernia after two methods for abdominal wound closure (rectus sheath relaxation incisions and conventional mass closure) was studied in a randomized prospective clinical trial in a consecutive series of 100 patients undergoing midline laparotomy for peritonitis. The two groups were well matched for etiologies of peritonitis, the surgical procedures performed, and the presence of known risk factors for fascial dehiscence. Fifty patients each were randomized either to the conventional continuous mass closure procedure or the rectus sheath relaxation incision technique (designed to increase wound elasticity and decrease tension in the suture line) using identical polypropylene sutures. The incidence of postoperative complications such as duration of ileus, chest infection, and wound infection were not statistically different between the two groups. The intensity of postoperative pain in the rectus sheath relaxation incision group was significantly less. The incidence of wound hematoma was significantly increased in the rectus sheath relaxation incision group. The incidences of fascial dehiscence (16% vs,28%; p < 0.05) and incisional hernia (18% vs, 30%; p < 0.05) were significantly lower after rectus sheath relaxation incisions compared to conventional mass closure. Closure of the midline laparotomy wound in cases of peritonitis using the rectus sheath relaxation technique is safe and less painful, provides increased wound elasticity and decreased tension on the suture line, and significantly decreases the incidence of wound dehiscence.
Impact of Age on Quality of Life in Patients with Rectal Cancer
Authors: Schmidt Christian E. , Bestmann Beate , Kuchler Thomas , Longo Walter E. , Kremer Bernd
Published: January 2005

Some studies indicate that age at the time of surgery has a general effect on outcomes. The impact of age on the quality of life (QOL) of patients with rectal cancer, however, has not been investigated. The present study was conducted to address this issue. Over a 5‐year period the European Organization for Research and Treatment of Cancer (EORTC)‐QLQ‐C‐30 and a tumor‐specific module were prospectively administered to patients before surgery, at discharge, and at 3, 6, 12, and 24 months postoperatively. Comparisons were made between age groups. A total of 519 patients participated in the study. QOL data were available for 253 patients. Significant differences were observed only between patients aged 69 years and younger (≤69 years) (169/253) and those aged 70 years and older (≥70 years) (85/253). Physical and role functioning was better for patients ≤69 years; patients ≥70 years suffered from increased pain and fatigue. Younger patients had more difficulty with sexual enjoyment, and over time sexual strain was worse for patients aged ≥70 years during the early postoperative period but improved, whereas patients aged ≤69 years had increasing levels of strain over time. The findings in this study confirmed that QOL is dynamic over time and that age has an impact on QOL and sexuality. Patients aged ≥70 years are affected by impaired physical functioning, global health, and fatigue, whereas increased treatment strain during the early postoperative period improves over time. Patients aged ≤69 years experience increased strain because of impaired sexual function.
Hemorrhage after Duodenopancreatectomy: Impact of Neoadjuvant Radiochemotherapy and Experience with Sentinel Bleeding
Authors: Turrini Olivier , Moutardier Vincent , Guiramand Jerome , Lelong Bernard , Bories Erwan , Sannini Antoine , Magnin Valerie , Viret Frederic , Blache Jean‐Louis , Giovannini Marc , Delpero Jean‐Robert
Published: January 2005

Postoperative hemorrhage (PH) after duodenopancreatectomy (DP) is frequently lethal. The aim of this study was to delineate guidelines of management. Between August 1994 and July 2003, 172 patients underwent DP for cancer. Altogether, 26 patients were subjected to an institutional protocol (IP) with standard‐dose chemoradiation (CRT) and 4 patients to an extrainstitutional protocol (EIP) with high‐dose CRT. Sixteen patients (9.3%) were reoperated for PH. Hemorrhage occurred in 23% of irradiated patients (4 EIP, 3 IP) and in 6% of nonirradiated patients [confidence interval (CI) 1.8‐6.5]. Pancreatic leak occurred in nine patients with PH (56%). Sentinel bleeding (SB) was noted in eight patients (50%) with a mean delay of 10 days after DP. Overall mortality after hemorrhage was 56%. Morality rates of patients with EIP or IP were, respectively, 100% and 0%. Mortality rates of patients with or without SB were similar. Mortality rates of axial bleeding (hepatic artery, mesenteric vessels) or lateral bleeding (pancreas remnant, splenic vessels) were, respectively, 88% and 25% (CI 1.6‐8.6). Completion of pancreatectomy was achieved in 75% without rebleeding. Preoperative high‐dose CRT increased the risk of fatal PH. Because SB occurs before massive hemorrhage, prompt reoperation could reduce mortality. Completion of pancreatectomy was essential during reintervention. Axial bleeding supports high mortality. Moving to the left, the pancreatojejunostomy could avoid contact of pancreatic juice with axial vessels in the case of pancreatic leakage. Ligating the gastroduodenal artery during DP had to leave a stump of around 1 cm to facilitate hemorrhage control without ligating the common hepatic artery.
Occult Intrabiliary Rupture of Hydatid Cysts in the Liver
Authors: Hamamci Enver Okan , Besim Hasan , Sonisik Muhittin , Korkmaz Atila
Published: January 2005

The aim of this study was to investigate the effects of various surgical modalities directed at the cavity of hydatid cysts in patients with occult intrabiliary rupture. In this respect, 324 patients with hydatid cyst of the liver operated on during 1983‐2003 were analyzed; among them, 39 patients with occult intrabiliary rupture were included in the study. Clinical symptomatology, physical examination, laboratory findings, results of imaging studies, the localization and size of the cyst, and operative findings were reviewed. Twelve patients had complications, and there was no mortality. The most common complication was bile fistula. The average postoperative hospital stay was 7.0 ± 3.8 days for patients with omentoplasty and 6.0 ± 2.5 days for those who underwent cavitary drainage. For patients who do not have bile‐stained cystic fluid, the utilization of scolicidal agents is appropriate. Although the opening of the duct is sutured when it is identified, the risk of biliary fistula is not clearly correlated with this approach. In such cases, omentoplasty provides a good alternative to cavitary drainage.
A Critical Evaluation of Hepatic Resection in Cirrhosis: Optimizing Patient Selection and Outcomes
Authors: Emond Jean C. , Samstein Benjamin , Renz John F.
Published: January 2005

Hepatic resection has long been the mainstay of treatment of primary liver cancers, particularly hepatocellular carcinoma (HCC). Because of the high incidence of cirrhosis in patients with HCC, the use of resection was initially limited by the ability of the cirrhotic liver to sustain the surgical insult and the mass reduction. Today, hepatectomy in cirrhosis is undergoing a remarkable evolution. Although surgical and anesthetic improvements have increased the safety of this option, the rapid development of alternative therapies has decreased the need for it. Local excision for small HCC is likely to be replaced by image‐guided, percutaneous ablative techniques. Furthermore, total replacement of a cirrhotic liver may be a more effective long‐term cure than resection. Unquestionably, resection remains the optimal approach for patients with large tumors and healthy underlying liver function. The role of rapidly evolving new approaches will remain the subject of intensive inquiry in the years to come. In this report, we have attempted to clarify current practice with respect to the evaluation, selection, and technique of resection in cirrhosis, and identify areas of active inquiry.
Confidentiality Governing Surgical Research Practice
Authors: Mavroforou Anna , Giannoukas Athanasios D. , Mavrophoros Dimitrios , Michalodimitrakis Emmanuel
Published: January 2005

Healthy subjects or patients volunteering to participate in trials expect that their privacy and autonomy will be protected. The aim of this article is to highlight issues related to confidentiality governing surgical research practice. A search of the current relevant literature was undertaken. Consent to the disclosure of any information should be sought wherever practicable, but disclosures should be kept to the minimum necessary. The data should be made anonymous where unidentifiable data serve the purpose. Where the previously described actions are not practicable for various reasons, data may be disclosed for research, provided participants have been given information about access to their records and about their right to object. Personal information may only be disclosed without individual’s consent when it is for the protection of the public interest, but this has proved too ambiguous a rubric to be useful without proper clarification. Hampering of noncommercial medical research should also be avoided, as it may cause serious damage to public health. Confidentiality in research is an important issue in the protection of the participants’ rights to privacy and autonomy, and it should be considered in the design of each study. Breach of confidentiality is legally justifiable for the sake of the public interest, but proper clarification of the law is required in order to avoid hampering noncommercial medical research that is vital for the public health.
Factors Predicting Long‐term Graft Survival after Kidney Transplantation: Multicenter Study in Japan
Authors: Akioka Kiyokazu , Takahara Sirou , Ichikawa Seiji , Yoshimura Norio , Akiyama Takahiro , Ohshima Shinichi
Published: January 2005

A multicenter retrospective study was conducted in 936 living donor kidney transplant recipients treated with cyclosporine (CsA) or tacrolimus (FK) from April 1982. The influences of acute rejection, hyperlipidemia, and hypertension were estimated by Kaplan‐Meier’s analysis and Wilcoxon’s analysis. Of 916 recipients, 532 (58.1%) had acute rejections. The 5‐ and 10‐year graft survival rates in the recipients with acute rejection were 75.2% and 55.2%, respectively. The corresponding rates of the recipients without acute rejection were 80.2% and 70.6%, respectively. The graft survival rate was worse in recipients with late‐phase rejection and multiple rejection episodes (p < 0.00006). Of 451 recipients, 176 (39.0%) had hypercholesterolemia 3 years after kidney transplantation. The 5‐ and 10‐year graft survival rates in the recipients with hypercholesterolemia were 88.7% and 68.7%, respectively. Those of the recipients without hypercholesterolemia were 95.2% and 83.9%, respectively. The graft survival rate in the recipients with hypercholesterolemia was lower than that in the recipients without hypercholesterolemia (p = 0.003). Of 323 recipients, 123 (38.1%) had hypertriglyceridemia 3 years after kidney transplantation. The 5‐ and 10‐year graft survival rates in the recipients with hypertriglyceridemia were 93.7% and 80.5%, respectively. Those in the recipients without hypertriglyceridemia were 95.1% and 86.5%, respectively. The graft survival rate in the recipients with hypertriglyceridemia was lower than that in the recipients without hypertriglyceridemia (p = 0.371). Of 367 recipients, 151 (41.1%) had systolic hypertension 3 years after kidney transplantation. The 5‐ and 10‐year graft survival rates in the recipients with hypertension were 85.6% and 64.7%, respectively. Those of the recipients without hypertension were 95.6% and 83.8%, respectively. The graft survival rate in the recipients with hypertension was lower than that in the recipients without hypertension (p < 0.001). Acute rejection, hyperlipidemia (hypercholesterolemia and hypertriglyceridemia), and hypertension are predictive factors for long‐term graft survival. Especially the onset time, number of rejections, and efficacy of treatment for acute rejection would have a significant influence on long‐term graft survival.
Identification of different specificity requirements between SGK1 and PKBα
Authors: Murray James T. , Cummings Lorna A. , Bloomberg Graham B. , Cohen Philip
Published: January 2005

NDRG1 is phosphorylated by SGK1 (but not PKB) in vivo at three residues each contained within three nonapeptide repeats. Here, we demonstrate that this nonapeptide, like the NDRG1 protein, is phosphorylated by SGK1, but not by PKBα or RSK1 in vitro. The inability of PKBα and RSK1 to phosphorylate the nonapeptide was traced to residues n
+ 1, n
+ 2 and n
− 4 (where n is the phosphorylation site). Changing them from Ser, Glu and Ser to Phe, Ala and Pro, respectively, transformed the nonapeptide into an excellent substrate for PKBα and RSK1. Our results identify a specific substrate for SGK1 and may facilitate detection of additional physiological substrates for this enzyme.
p53 is a NF‐Y‐ and p21‐independent, Sp1‐dependent repressor of cyclin B1 transcription
Authors: Innocente Steven A. , Lee Jonathan M.
Published: January 2005

The p53 tumour suppressor protein is a DNA‐binding transcription factor activated in response to DNA damage. Inactivation of the p53 gene occurs in 40–60% of human tumours and a substantial body of work indicates that loss of p53 activity is a critical step in oncogenesis. p53 helps to protect against neoplasia by inducing death in cells that have sustained irreparable DNA damage or by blocking cell cycle progression to allow time for DNA repair. We have previously reported that p53 prevents G2/M transition by decreasing intracellular levels of cyclin B1 protein and attenuating the activity of the cyclin B1 promoter [S.A. Innocente, J.L. Abrahamson, J.P. Cogswell, J.M. Lee, p53 regulates a G2 checkpoint through cyclin B1, Proc. Natl. Acad. Sci. USA 96 (1999) 2147–2152]. The ability of p53 to control mitotic initiation by regulating intracellular cyclin B1 levels suggests that a cyclin B1‐dependent G2 checkpoint has a role in preventing neoplastic transformation. Here, we show that p53‐mediated attenuation of the cyclin B1 promoter occurs in both p21+/+ and p21−/− cell lines. Furthermore, promoter attenuation is dependent on the presence of functional Sp1 binding sites and is independent of the NF‐Y binding sites. We also find that wild‐type, but not mutant, p53 protein binds Sp1 and the cyclin B1 promoter. This suggests that wild‐type p53 mediates transcriptional repression of cyclin B1 through the Sp1 transcription factor.
A Rieske ferredoxin typifying a subtype within Rieske proteins: spectroscopic, biochemical and stability studies
Authors: Kletzin Arnulf , Ferreira Ana S. , Hechler Torsten , Bandeiras Tiago M. , Teixeira Miguel , Gomes Cláudio M.
Published: January 2005

A new subtype of archaeal Rieske ferredoxin (RFd) has been identified in the genome of the thermoacidophilic archaeon Acidianus ambivalens. The gene is inserted in an atypical genomic context in a gene cluster encoding a NiFe hydrogenase. Sequence and phyletic analysis showed that the protein is related to bacterial RFd but not to any of the known archaeal Rieske proteins. The recombinant 14 kDa protein isolated from Escherichia coli behaved as a dimer in solution. It contained ∼2 Fe/mol and all visible and EPR spectroscopic features typical of Rieske centre‐containing proteins. However, its redox potential (+170 mV) was significantly higher than those of canonical RFd. This difference is rationalized in terms of the protein structure environment, as discrete amino acid substitutions in key positions around the metal centre account for the higher potential.
Small Jab1‐containing subcomplex is regulated in an anchorage‐ and cell cycle‐dependent manner, which is abrogated by ras transformation
Authors: Fukumoto Akihisa , Tomoda Kiichiro , Kubota Makoto , Kato Jun-ya , Yoneda-Kato Noriko
Published: January 2005

Jab1 interacts with a variety of cell cycle and signal transduction regulators to control cell proliferation, differentiation, and tumorigenesis. In this study, we employed a non‐denaturing gel electrophoresis method to separate different Jab1‐containing complexes, the COP9 signalosome complex and the small Jab1‐containing subcomplex. The formation of the small Jab1 complex was dependent on a low cell density and anchorage to a solid support, and enhanced during the early G1 phase of the cell cycle, which was abrogated in ras‐transformed cells. The small Jab1‐containing subcomplex may be a novel mediator of anchorage and cell–cell contact‐dependent signal transduction.
An investigation of the activity of recombinant rat skeletal muscle cytosolic sialidase
Authors: Albouz-Abo Samia , Turton Richard , Wilson Jennifer C. , von Itzstein Mark
Published: January 2005

Rat cytosolic sialidase is expressed at elevated levels in skeletal muscle and is believed to play a role in the myogenic differentiation of muscle cells. Here, we observed varying levels of enhancement of sialidase activity in the presence a range of divalent cations. In particular, a significant enhancement of activity was observed in the presence of Ca2+. Conversely, inhibition of the sialidase activity was found when the enzyme was incubated in the presence of Cu2+, EDTA, and a range of carbohydrate‐based inhibitors. Finally, an investigation of the enzymatic hydrolysis of a synthetic substrate, 4‐methylumbelliferyl N‐acetyl‐α‐d‐neuraminide, by 1H NMR spectroscopy revealed that the reaction catalysed by rat skeletal muscle cytosolic sialidase proceeds with overall retention of anomeric configuration. This result further supports the notion that all sialidases appear to be retaining enzymes.
Interchange of aequorin and obelin bioluminescence color is determined by substitution of one active site residue of each photoprotein
Authors: Stepanyuk Galina A. , Golz Stefan , Markova Svetlana V. , Frank Ludmila A. , Lee John , Vysotski Eugene S.
Published: January 2005

The bioluminescence spectra from the Ca2+‐regulated photoproteins aequorin (λ
max
= 469 nm) and obelin (λ
max
= 482 nm) differ because aequorin has an H‐bond from its Tyr82 to the bound coelenteramide, not present in obelin at the corresponding Phe88. Substitutions of this Phe88 by Tyr, Trp, or His shifted the obelin bioluminescence to shorter wavelength with F88Y having λ
max
= 453 nm. Removal of the H‐bond by the substitution of Y82F in aequorin shifted its bioluminescence to λ
max
= 501 nm. All mutants were stable with good activity and were expressible in mammalian cells, thereby demonstrating potential for monitoring multiple events in cells using multi‐color detection.
IFN‐γ/IRF‐1‐induced p27kip1 down‐regulates telomerase activity and human telomerase reverse transcriptase expression in human cervical cancer
Authors: Lee Seung-Hoon , Kim Jung-Whan , Oh Sun-Hee , Kim Yong-Jin , Rho Seung-Bae , Park Kyungsook , Park Kui-Lea , Lee Je-ho
Published: January 2005

Telomerase activation is regulated by the expression of human telomerase reverse transcriptase (hTERT) and is a key step in the development of human cancers. Interferon‐γ (IFN‐γ) signaling induces growth arrest in many tumors through multiple regulatory mechanisms. The p27 tumor suppressor protein inhibits the formation of tumors through the induction of cell cycle arrest and/or apoptosis. We demonstrate here that p27
Kip1
inhibits hTERT mRNA expression and telomerase activity through post‐transcriptional up‐regulation by IFN‐γ/IRF‐1 signaling. The ectopic expression of p27 suppressed hTERT expression and telomerase activity in human cervical cancer cell lines, HeLa and HT3. Furthermore, hTERT promoter activity of mouse embryonic fibroblasts (MEFs) deficient in p27 (p27−/− MEFs) was significantly higher than that of wild‐type MEFs. Overexpression of p27 suppressed hTERT promoter activity and telomerase activity of p27−/− MEFs. In addition p27 down‐regulated E7 protein expression and in transiently transfected HeLa cells, E7 increased hTERT promoter activity. In conclusion, we propose that inhibition of the hTERT expression and telomerase activity may be a novel tumor suppressor function of p27.
Zizimin2: a novel, DOCK180‐related Cdc42 guanine nucleotide exchange factor expressed predominantly in lymphocytes
Authors: Nishikimi Akihiko , Meller Nahum , Uekawa Natsuko , Isobe Ken-ichi , Schwartz Martin A. , Maruyama Mitsuo
Published: January 2005

A novel superfamily of guanine nucleotide exchange factors for Rho GTPases includes DOCK180 and zizimin1. The zizimin subfamily includes three genes of which only zizimin1 has been cloned. We report here the cloning of zizimin2, identified in a screen for genes enriched in germinal center B cells. Zizimin2 and zizimin1 have similar primary structures and both proteins bound and activated Cdc42 but not the Cdc42‐related proteins TC10 or TCL. Their tissue distributions are distinct, however, with zizimin2 expressed predominantly in lymphocytes and an opposite pattern for zizimin1. Zizimin3 was also analyzed and showed distinct GTPase specificity and tissue distribution.
Food and feeding ecology of juvenile albacore, Thunnus alalunga, off the Bay of Biscay: a case study
Authors: Pusineri C. , Vasseur Y. , Hassani S. , Meynier L. , Spitz J. , Ridoux V.
Published: January 2005

Although immature albacore tuna, Thunnus alalunga, are of economic and social importance in the Bay of Biscay, little is known about their diet and feeding ecology there. For this study, the diet of 78 albacore caught in the French driftnet fishery during summer 1993 is analysed. Fish dominated the diet in terms of relative abundance (86%N), and reconstituted mass (60%M), the most important being Maurolicus muelleri (79%N, 23%M), Scomberesox saurus (2%N, 30%M), and Arctozenus risso (4%N, 4%M). Crustaceans were also important in the diet (12%N, 2%M), but given their small size, it is questionable whether they were primary or secondary prey. Foraging on cephalopods seemingly took place only occasionally: they represented 2%N and 39%M of the total diet, but were absent from the fresh fraction of stomach contents. Prey sizes ranged from 6 to 228 mm. Juvenile albacore consume either epipelagic prey by day, or vertically migrating mesopelagic species that reach the surface layer by night.
Ethnic background and in vitro fertilization outcomes
Authors: Bendikson K. , Cramer D.W. , Vitonis A. , Hornstein M.D.
Published: January 2005

Objective

To compare IVF outcomes among women of different ethnic backgrounds.

Method

This was a retrospective cohort study. Between August 1994 and March 1998, the first IVF cycles of 1039 white, 43 African American, 18 Hispanic, and 35 Asian women were examined.

Result

Ages and day 3 FSH levels did not differ significantly among patients. African Americans weighed more than other ethnic groups and were also more likely to have tubal factor infertility than whites. IVF cycle characteristics did not vary among the ethnic groups with the exception that African Americans had a higher level of estradiol on day of HCG than whites. Pregnancy outcomes did not differ among the ethnic groups. The percentage of ectopic pregnancies, spontaneous abortions, and successful live births was similar among the groups.

Conclusion

Our data showed no significant difference in pregnancy outcomes with IVF among the ethnic groups.
Role of late glacial to mid-Holocene climate in catchment weathering in the central Tibetan Plateau
Authors: Jin Zhang-Dong , Wu Yanhong , Zhang Xiaohui , Wang Sumin
Published: January 2005

The lightness (L*) and concentrations of Rb, Sr and organic carbon (Corg) have been measured in the age-constrained lake sediment cores recovered from Co Ngoin in the central Tibetan Plateau. Dissolved Sr flux is a dominant control on the variation of Rb/Sr ratios in the sediments. Variations in color and geochemical proxies of Co Ngoin sediments display a continuous history of late glacial to mid-Holocene chemical versus physical weathering intensity in response to past climatic changes between approximately 13,500 and 4500 cal yr B.P. A lower chemical weathering under a late glacial climate was followed by a higher weathering during the Holocene Optimum. Weathering intensity in the central Tibetan Plateau catchment also responds to well-known climatic events, such as the Younger Dryas (YD), and possibly the Holocene Event 5 (HE-5). Although there are differences in time or duration of the climatic events, many of the well-known late glacial to mid-Holocene events occurred in high-elevation Co Ngoin where atmospheric circulation might play a hemispherical role in climatic forcing. The sediment hiatus since c. 4200 14C yr B.P. in the Co Ngoin indicates a period of desiccation that was probably associated with a sharp decrease in summer monsoon strength. Our lascustrine results not only imply catchment weathering variations in response to late glacial to mid-Holocene climatic conditions in the central plateau, but also provide further evidence for global connections between regional climates.
Climate change on the Yucatan Peninsula during the Little Ice Age
Authors: Hodell David A. , Brenner Mark , Curtis Jason H. , Medina-González Roger , Ildefonso-Chan Can Enrique , Albornaz-Pat Alma , Guilderson Thomas P.
Published: January 2005

We studied a 5.1-m sediment core from Aguada X'caamal (20° 36.6′N, 89° 42.9′W), a small sinkhole lake in northwest Yucatan, Mexico. Between 1400 and 1500 A.D., oxygen isotope ratios of ostracod and gastropod carbonate increased by an average of 2.2‰ and the benthic foraminifer Ammonia beccarii parkinsoniana appeared in the sediment profile, indicating a hydrologic change that included increased lake water salinity. Pollen from a core in nearby Cenote San José Chulchacá showed a decrease in mesic forest taxa during the same period. Oxygen isotopes of shell carbonate in sediment cores from Lakes Chichancanab (19° 53.0′N, 88° 46.0′W) and Salpeten (16° 58.6′N, 89° 40.5′W) to the south also increased in the mid-15th century, but less so than in Aguada X'caamal. Climate change in the 15th century is also supported by historical accounts of cold and famine described in Maya and Aztec chronicles. We conclude that climate became drier on the Yucatan Peninsula in the 15th century A.D. near the onset of the Little Ice Age (LIA). Comparison of results from the Yucatan Peninsula with other circum-Caribbean paleoclimate records indicates a coherent climate response for this region at the beginning of the LIA. At that time, sea surface temperatures cooled and aridity in the circum-Caribbean region increased.
A New Species in the Lecanora Subfusca Group Containing Usnic Acid in Addition to Atranorin
Authors: Lumbsch H. Thorsten
Published: January 2005

Lecanora pseudogangaleoides spec. nov. is a saxicolous lichen in southeastern Australia. It fits anatomically into the L. subfusca group (=Lecanora s.str.), but differs from most previous concepts of that group in containing usnic acid in addition to atranorin. The presence of usnic acid is now considered to be of less importance in that group, and species containing usnic acid may well belong to Lecanora s.str. Within L. pseudogangaleoides chemical variation with respect to the presence of xanthones was observed and two subspecies are distinguished. Lecanora pseudogangaleoides s.str. lacks xanthones, whereas L. pseudogangaleoides subsp. verdonii subsp. nov. contains the arthothelin chemosyndrome in addition to the normal occurrence of the psoromic acid chemosyndrome. A key orthe distinction of L. pseudogangaleoides and similar species is included.
Medullary Structure of the Umbilicariaceae
Authors: Valladares Fernando , Sancho Leopoldo G.
Published: January 2005

The medullary structure of 24 Umbilicariaceae species was studied by light microscopy. The objective was to investigate the variability of the medulla of these lichens and to assess the possible implications for thallus ecophysiology and the taxonomic relevance of the anatomy of this layer. Several methods of embedding, sectioning and staining together with the comparison of radial with transverse sections showed important differences in the degree of cohesion of hyphae and their spatial orientation within the medulla. Other important characteristics were the existence of more than one structurally homogeneous layer within the medulla, the frequency of hyphal branching, the relative thickness of the cell wall and lumen and the abundance of gelatinous matter in the intercellular spaces. The medullae studied were grouped into seven main types. The constancy of the types of medulla for certain groups of species makes it a useful secondary character to be considered in the taxonomy of the Umbilicariaceae. The important role of the structure of the medulla in the water relations of the Umbilicariaceae is discussed and a general relationship between medulla type and hydration strategy is suggested
Secondary Metabolites from Isolated Lichen Mycobionts Cultured Under Different Osmotic Conditions
Authors: Hamada Nobuo , Miyagawa Hisashi
Published: January 2005

Growth of the mycobiont of Ramalina siliquosa and the secondary metabolites subsequently produced under various osmotic culture conditions were examined. The secondary metabolite content and the growth rate changed greatly when different quantities of sucrose were added to the culture medium. Salazinic acid was found only in mycobionts cultured on a medium with 10 or 20% sucrose, the mycobiont growth rate being higher than on conventional medium. Similarly, in Lobaria discolor, gyrophoric acid was found only in mycobionts cultured on a medium with 10% sucrose.
A Rapid and Inexpensive Method for the Purification of DNA from Lichens and their Symbionts
Authors: Armaleo Daniele , Clerc Philippe
Published: January 2005

A simple DNA extraction method is described, applicable to many different kinds of lichens. The method involves the use of the detergents DTAB and CTAB and yields DNA that can be directly amplified with the polymerase chain reaction or digested with restriction enzymes
Effect of Acute Gamma Radiation on some Physiological Features of Lichens
Authors: Nifontova M. G. , Ravinskaya A. P. , Shapiro I. A.
Published: January 2005

The influence of acute gamma radiation on four physiological characteristics of lichens was investigated. Membrane permeability in irradiated thalli of Cladonia arbuscula, Cetraria islandica and Hypogymnia physodes increased considerably compared to controls. The nitrogen content in Peltigera aphthosa appeared to be stable to acute gamma radiation. Up to 1000 Gy there was no essential decrease in respiration intensity in H. physodes and P. aphthosa or of peroxidase activity in P. aphthosa..
Status of nesting loggerhead turtles Caretta caretta at Bald Head Island (North Carolina, USA) after 24 years of intensive monitoring and conservation
Authors: Hawkes Lucy A. , Broderick Annette C. , Godfrey Matthew H. , Godley Brendan J.
Published: January 2005

A 24-year set of data from monitoring of a nesting beach at Bald Head Island, North Carolina, USA, was analysed in parallel with limited data from nearby rookeries to investigate trends in loggerhead turtle Caretta caretta nesting numbers. There was no statistical evidence of an increasing or decreasing trend in numbers of clutches laid per year, although a significant decrease in the number of turtles nesting and number of clutches laid per year was found from 1991. Remigrating turtles were larger and had larger annual clutch frequencies than neophyte turtles. Annual levels of nesting at beaches within the Cape Fear area were significantly correlated. The stable trend in number of clutches laid across more than two decades is discussed in relation to other factors affecting marine turtles in North American waters.
Calving of large tabular icebergs from ice shelf rift systems
Authors: Joughin Ian , MacAyeal Douglas R.
Published: January 2005

We used Interferometric Synthetic Aperture Radar to study the detachment process that allowed two large icebergs to calve from the Ross Ice Shelf, Antarctica. Time series of rift geometries indicate that rift widths increased steadily, whereas rift lengths increased episodically through several discrete rift‐tip propagation events. We also conducted modeling experiments constrained by the observed rift geometry. Both the observations and model suggest that rift opening, and, thus, tabular‐iceberg calving, are largely driven by “glaciological” stresses—stress introduced by the effect of gravity on the ice shelf—rather than by stress introduced by the ocean and atmosphere, e.g., tides and storms. This style of rift propagation is expected to determine the steady, background calving rate of ice shelves and, thus, differs significantly from styles that led to the recent disintegration of ice shelves in response to climate warming, e.g., the Larsen B Ice Shelf on the Antarctic Peninsula.