bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Mycoplasma pneumoniae MPN229 gene encodes a protein that selectively binds single-stranded DNA and stimulates Recombinase A-mediated DNA strand exchange
Authors: Sluijter Marcel , Hoogenboezem Theo , Hartwig Nico G , Vink Cornelis 
Published: October 2008

Abstract

Background

Mycoplasma pneumoniae has previously been characterized as a micro-organism that is genetically highly stable. In spite of this genetic stability, homologous DNA recombination has been hypothesized to lie at the basis of antigenic variation of the major surface protein, P1, of M. pneumoniae. In order to identify the proteins that may be involved in homologous DNA recombination in M. pneumoniae, we set out to characterize the MPN229 open reading frame (ORF), which bears sequence similarity to the gene encoding the single-stranded DNA-binding (SSB) protein of other micro-organisms.

Results
The MPN229 ORF has the capacity to encode a 166-amino acid protein with a calculated molecular mass of 18.4 kDa. The amino acid sequence of this protein (Mpn SSB) is most closely related to that of the protein predicted to be encoded by the MG091 gene from Mycoplasma genitalium (61% identity). The MPN229 ORF was cloned, and different versions of Mpn SSB were expressed in E. coli and purified to > 95% homogeneity. The purified protein was found to exist primarily as a homo-tetramer in solution, and to strongly and selectively bind single-stranded DNA (ssDNA) in a divalent cation- and DNA substrate sequence-independent manner. Mpn SSB was found to bind with a higher affinity to ssDNA substrates larger than 20 nucleotides than to smaller substrates. In addition, the protein strongly stimulated E. coli Recombinase A (RecA)-promoted DNA strand exchange, which indicated that Mpn SSB may play an important role in DNA recombination processes in M. pneumoniae.

Conclusion
The M. pneumoniae MPN229 gene encodes a protein, Mpn SSB, which selectively and efficiently binds ssDNA, and stimulates E. coli RecA-promoted homologous DNA recombination. Consequently, the Mpn SSB protein may play a crucial role in DNA recombinatorial pathways in M. pneumoniae. The results from this study will pave the way for unraveling these pathways and assess their role in antigenic variation of M. pneumoniae.
Rapid progression of traumatic bifrontal contusions to transtentorial herniation: A case report
Authors: Rehman Tausif , Ali Rushna , Tawil Isaac , Yonas Howard 
Published: October 2008

Abstract
We report a case of mild to moderate traumatic brain injury in which ICP monitoring or quantitative cerebral perfusion data may have allowed earlier recognition of impending herniation, avoidance of a secondary insult, and ultimately resulted in a better outcome, even though the patient did not meet the standard guidelines of the Brain Trauma Foundation. A thirty-five year old male who presented with traumatic bifrontal contusions and GCS of fourteen and twelve hours later progressed rapidly to having dilated pupils and transtentorial/central herniation over the course of fifteen minutes. The patient was taken emergently for a bifrontal craniectomy. Post operatively he had an acute infarct in the posterolateral left temporal lobe with expected evolution of parenchymal contusions as well as infarcts in the splenium of the corpus callosum, left thalamus and medial right occipital lobe. This case signifies an exception from the guidelines submitted by the Brain Trauma Foundation for intracranial pressure monitoring in patients with severe brain injury.
We also point out previous reports which state that in such a patient a more sensitive test for detection would perhaps be quantitative blood flow monitoring, and may have led to a better outcome. We recommend using intracranial pressure monitoring or blood flow measurements to trend patients with bifrontal intraparenchymal contusions and GCS greater than eight to prevent clinically undetected deterioration from transtentorial/central herniation.
Acute hepatic failure due to dengue: A case report
Authors: Giri Subhash , Agarwal Mukul P , Sharma Vishal , Singh Ankur 
Published: October 2008

Abstract
Dengue is an arboviral disease endemic in many parts of the world. Although it is known to cause hepatic involvement commonly, it only occasionally results in acute hepatic failure. We present the case of a young male who developed acute hepatic failure due to dengue. The differentials and the management is discussed.
Bone Morphogenetic Protein-2 Antagonizes Renal Interstitial Fibrosis by Promoting Catabolism of Type I Transforming Growth Factor-β Receptors
Authors: Yang Yu-Lin , Liu Yi-Shiuan , Chuang Lea-Yea , Guh Jinn-Yuh , Lee Tao-Chen , Liao Tung-Nan , Hung Min-Yuan , Chiang Tai-An 
Published: October 2008

TGF-β is a therapeutic target for renal fibrosis. Scientists have long sought ways to antagonize TGF-β to ameliorate diabetic nephropathy. Bone morphogenetic protein (BMP-2) is a member of the TGF-β superfamily and is highly regulated in the kidney. Thus, the role of BMP-2 was investigated in NRK-49F cells (rat fibroblasts). We showed that TGF-β1 induces an increase in fibronectin. Treatment with exogenous BMP-2 or pCMV-BMP-2 significantly reversed the TGF-β1-induced increase in fibronectin concomitant with a significant decrease in type I TGF-β receptors (TGF-β RI). Moreover, BMP-2 significantly shortened the half-life of TGF-β RI. These results are related to proteosomal activation because MG132, a proteasome inhibitor, abolished BMP-2-mediated degradation of TGF-β RI. This was confirmed because BMP-2 time course dependently enhanced the ubiquitination level of TGF-β RI. In addition, Smads would seem to be involved in the interaction of BMP-2 and TGF-β. We demonstrated that BMP-2 significantly reversed the TGF-β1-induced increase in pSmad2/3 and reversed the TGF-β1-induced decrease in inhibitory Smad7. Most importantly, Smad7 small interfering RNA abolished the BMP-2-induced decrease in TGF-β RI. We evaluated the clinical efficacy of BMP-2 using unilateral ureteral obstruction rats. BMP-2 was administered ip for 7 d. In the unilateral ureteral obstruction kidneys, interstitial fibrosis was prominent. However, treatment with BMP-2 dramatically reduced Masson’s trichrome staining (collagen) in the interstitial and tubular areas of the kidneys concomitantly with a reduction in TGF-β RI. These results suggest that BMP-2 acts as a novel fibrosis antagonizing cytokine partly by down-regulating TGF-β RI and Smads.Bone morphogenetic protein-2 can antagonize TGF-β-inducing cellular fibrosis by intervening post-receptors signaling, thus disclosing an application of therapeutical potential against fibrosis disorders.
Expression of Scavenger Receptor-BI and Low-Density Lipoprotein Receptor and Differential Use of Lipoproteins to Support Early Steroidogenesis in Luteinizing Macaque Granulosa Cells
Authors: Cherian-Shaw Mary , Puttabyatappa Muraly , Greason Erin , Rodriguez Annabelle , VandeVoort Catherine A. , Chaffin Charles L. 
Published: October 2008

An ovulatory hCG stimulus to rhesus macaques undergoing controlled ovarian stimulation protocols results in a rapid and sustained increase in progesterone synthesis. The use of lipoproteins as a substrate for progesterone synthesis remains unclear, and the expression of lipoprotein receptors [very-low-density lipoprotein receptor (VLDLR), low-density lipoprotein receptor (LDLR), and scavenger receptor-BI (SR-BI)] soon after human chorionic gonadotropin (hCG) (&lt;12 h) has not been characterized. This study investigated lipoprotein receptor expression and lipoprotein (VLDL, LDL, and HDL) support of steroidogenesis during luteinization of macaque granulosa cells. Granulosa cells were aspirated from rhesus monkeys undergoing controlled ovarian stimulation before or up to 24 h after an ovulatory hCG stimulus. The expression of VLDLR decreased within 3 h of hCG, whereas LDLR and SR-BI increased at 3 and 12 h, respectively. Granulosa cells isolated before hCG were cultured for 24 h in the presence of FSH or FSH plus hCG with or without VLDL, LDL, or HDL. Progesterone levels increased in the presence of hCG regardless of lipoprotein addition, although LDL, but not HDL, further augmented hCG-induced progesterone. Other cells were cultured with FSH or FSH plus hCG without an exogenous source of lipoprotein for 24 h, followed by an additional 24 h culture with or without lipoproteins. Cells treated with hCG in the absence of any lipoprotein were unable to maintain progesterone levels through 48 h, whereas LDL (but not HDL) sustained progesterone synthesis. These data suggest that an ovulatory stimulus rapidly mobilizes stored cholesterol esters for use as a progesterone substrate and that as these are depleted, new cholesterol esters are obtained through an LDLR- and/or SR-BI-mediated mechanism.An ovulatory stimulus to primate granulosa cells increases the expression of low-density lipoprotein (LDL) receptor and scavenger receptor class B, type I, while LDL serves as the primary substrate for progesterone synthesis.
Estrogen Receptor-α Mediates the Epidermal Growth Factor-Stimulated Prolactin Expression and Release in Lactotrophs
Authors: Ben-Jonathan Nira , Chen Shenglin , Dunckley Joseph A. , LaPensee Christopher , Kansra Sanjay 
Published: October 2008

Epidermal growth factor (EGF) is a potent regulator of cell function in many cell types. EGF-receptor (EGFR/ErbB1)-activated Erk1/2 has been reported to activate estrogen receptor (ER) in an estrogen (E2)-independent manner. In the pituitary lactotrophs, both EGF and E2 stimulate prolactin (PRL) release, but the nature of interactions between ErbB and ERα signaling is unknown. Our objectives were to 1) characterize EGF-induced PRL release, 2) determine whether this effect requires ERα, and 3) determine the molecular basis for cross talk between ErbB and ERα signaling pathways. Using GH3 cells, a rat lactotroph cell line, we report that EGF stimulates PRL gene expression and release in a dose- and time-dependent manner. EGF caused a rapid and robust activation of Erk1/2 via ErbB1 and induced phosphorylation of S118 on ERα in an Erk1/2-dependent manner. The global antiestrogen ICI 182780 and the ERα-specific antagonist 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylet hoxy)phenol]-1H-pyrazole dihydrochloride (MPP), but not the ERβ-specific antagonist 4-[2-Phenyl-5,7-bis(trifluoromethyl) pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP), blocked the EGF-induced PRL release, indicating an ERα requirement. This was further supported by using ERα knockdown by small interfering RNA. Because the antiestrogens did not block EGF-induced Mek-1 or Erk1/2 phosphorylation, ERα is placed downstream from the ErbB1-activated Erk1/2. These results provide the first evidence that ErbB1-induced PRL release is ERα dependent.Epidermal growth factor-stimulated prolactin release in lactotrophs is dependent upon estrogen receptor α.
Inactivation of the Human Vitamin D Receptor by Caspase-3
Authors: Malloy Peter J. , Feldman David 
Published: October 2008

Calcitriol actions are mediated by the vitamin D receptor (VDR), a nuclear transcription factor of the steroid-retinoid-thyroid nuclear receptor gene superfamily. Calcitriol inhibits the growth of many cells including cancer cells by inducing cell cycle arrest. In some cancer cell lines, calcitriol also induces apoptosis. In the LNCaP prostate cancer cell line, induction of apoptosis and caspase-3/7 activities by staurosporine (STS) abolished [3H]1,25-dihydroxy vitamin D3 binding and VDR protein, suggesting that the VDR may be targeted for inactivation by caspases during apoptosis. A potential caspase-3 site (D195MMD198S) was identified in the human VDR ligand-binding domain. Mutations D195A, D198A, and S199A were generated in the putative capase-3 cleavage site. In transfected COS-7 cells, STS treatment resulted in the cleavage of the wild-type (WT) VDR and S199A mutant VDR but not the D195A or D198A mutants. In in vitro assays, the WT VDR and S199A mutant VDR were cleaved by caspase-3, although the D195A and D198A mutants were resistant to caspase-3. In vitro, the WT VDR was also cleaved by caspase-6 and caspase-7 and in extracts of STS-treated LNCaP cells. In STS-treated LNCaP cells and human skin fibroblasts, the proteasome inhibitor MG-132 protected the VDR caspase cleavage fragment from further degradation by the 26S proteasome. The rat VDR that does not contain the caspase-3 cleavage site was not cleaved in STS-treated COS-7 cells. In conclusion, our results demonstrate that the human VDR is a target of caspase-3 and suggest that activation of caspase-3 may limit VDR activity.
The vitamin D receptor contains a caspase-3 cleavage site in the ligand-binding domain that can be cleaved by caspase-3 in vitro and in intact cells.
Decreased Oocyte-Granulosa Cell Gap Junction Communication and Connexin Expression in a Type 1 Diabetic Mouse Model
Authors: Ratchford Ann M. , Esguerra Cybill R. , Moley Kelle H. 
Published: October 2008

AbstractIn women, type 1 diabetes is associated with an increased risk of poor prenatal outcomes such as congenital anomalies and early miscarriage. In murine models of type 1 diabetes, impaired oocyte meiotic maturation, abnormal oocyte metabolism, and increased granulosa cell apoptosis have been noted. because gap junction communication is critical for the regulation of oocyte growth and meiotic maturation, we investigated the level of communication between the oocyte and surrounding cumulus cells in a streptozotocin-induced type 1 diabetic B6SJL/F1 mouse model and the expression of gap junction proteins known as connexins. Fluorescence recovery after photobleaching analyses of cumulus cell-enclosed oocytes (CEOs) from diabetic mice showed a 60% decrease in communication as compared with CEOs from nondiabetic mice. Real-time RT-PCR analyses confirmed the presence of Cx26, Cx37, and Cx57 mRNA and revealed a significant decrease in Cx37 mRNA expression in oocytes from diabetic mice compared with nondiabetic mice. Western analyses detected Cx26 expression in CEO but not denuded oocyte (DO) samples, and Cx37 in DO samples. Cx26 protein levels were decreased by 78% in CEOs from diabetic mice, and Cx37 protein levels were decreased 36% in DOs from diabetic mice. This decrease in connexin expression and gap junction communication in CEOs from diabetic mice may be responsible for the impaired oocyte meiotic maturation and poor pregnancy outcomes.
Civilian Abdominal Gunshot Wounds in Durban, South Africa: A Prospective Study of 78 Cases
Authors: Chamisa Inchien 
Published: October 2008

INTRODUCTION Violence has become part and parcel of the daily routine of living in South Africa. This prospective study of 78 patients who sustained abdominal gunshot wounds was undertaken to evaluate the pattern of injuries, treatment outcome and the role of selective conservative management. PATIENTS AND METHODS All patients with abdominal gunshot wounds admitted into the accident and emergency department of Prince Mshyeni Memorial Hospital (PMMH) between January 2005 and June 2005 were included in this prospective study. Case notes were reviewed and data entered on a standard proforma by a single observer (IC). RESULTS A total of 78 patients who sustained abdominal gunshot wounds were included in the study. There were 68 males and 10 females with an age range of 16–60 years (median age, 25 years). Of these, 59 (76%) underwent emergency laparotomy and 19 (24%) were initially observed. Two patients in the observed group needed a delayed laparotomy, both with positive findings. Fifty-five (71%) patients had one entrance wound each and 23 (29%) had multiple entrance wounds. Forty-one (53%) patients had exit wounds and in 37 (47%) the bullet remained lodged in the body. The entrance wounds were in anterior abdominal wall in 50 patients, posterior trunk in 13, gluteal region in 11 and thorax in 4 patients, respectively. Twelve patients died, all from the emergency laparotomy group. There were two negative laparotomies from the laparotomy group. CONCLUSIONS Management of gunshot wounds is expensive and requires a variety of surgical skills. We recommend that a national database to which all gunshot wounds must be reported is required in order to assess the magnitude of the problem nationally as well as funding of research in injury control. This study along with many others shows that selective conservative management is feasible without the use of expensive investigations.
Management of Gingivobuccal Complex Cancer
Authors: Misra Sanjeev , Chaturvedi Arun , Misra NC 
Published: October 2008

INTRODUCTION Squamous cell carcinoma of the oral cavity ranks as the 12th most common cancer in the world and the 8th most frequent in males. It accounts for up to one-third of all tobacco-related cancers in India. Cancer of the gingivobuccal complex is especially common in Indians due to their tobacco habits. This review focuses on the management of lower gingivobuccal complex cancers. PATIENTS AND METHODS References for this review were identified by search of Medline and other bibliographic information available in the PubMed database. The search terms carcinoma oral cavity, and cancer oral cavity, buccal mucosa, gingiva, gingivobuccal complex, and alveolus cancer/carcinoma were used. References from relevant articles and abstracts from international conferences were also included. Only articles published in the English language were used. RESULTS Treatment of gingivobuccal complex cancer is primarily surgical. Radical neck dissection, or its modification, is the standard treatment for the node-positive neck. Supraomohyoid neck dissection is the accepted treatment for the node-negative neck. Radiotherapy is usually not the preferred modality of treatment for early gingivobuccal complex cancer. It is used either as postoperative adjuvant treatment or as definitive treatment for advanced cancer with or witihout chemotherapy. Chemotherapy has been used as neo-adjuvant, adjuvant or palliative treatment. Advanced cancers are common and continue to pose a challenge to the multidisciplinary team. CONCLUSIONS Gingivobuccal complex cancer remains a major public health problem despite being highly preventable and easily detectable. Advanced cancers constitute a major proportion of patients presenting for treatment. These patients are difficult to treat and have a poor outcome.
Assessment of Magnification of Digital Pelvic Radiographs in Total Hip Arthroplasty Using Templating Software
Authors: White SP , Bainbridge J , Smith EJ 
Published: October 2008

INTRODUCTION Templating of pelvic radiographs traditionally involved using implant-company provided acetates which assumed a magnification of 115–120%. With the introduction of digital imaging, many departments are becoming filmless. Templating software has been designed to allow on-screen templating of digital images. Knowledge of the true magnification of the image is required for accurate measurement. PATIENTS AND METHODS Fifty consecutive postoperative pelvic radiographs were analysed using templating software. The implanted component was measured using an assumed magnification factor of 115%. The template image was then reset to the known component size, and the magnification factor was adjusted until the template covered the true component. RESULTS An assumed magnification factor of 115% oversized the acetabular component by a mean of 6 mm (three component sizes) in all 50 components. The mean true magnification in our department was 127%. CONCLUSIONS Validation of the true magnification produced by a radiology department using templating software is a simple and reproducible technique. It is recommended to all departments using digital images and templating software. Assumption of a magnification factor of 115% risks oversizing components by 6mm.
From Small Acorns – Developing a Laparoscopic Colorectal Surgical Service
Authors: Smith JK , Acheson AG , Simpson JAD , Stewart J , Beckingham IJ , Gornall CB , Williams JP , Robinson MH , Maxwell-Armstrong CA 
Published: October 2008

INTRODUCTION Randomised controlled trials have shown that laparoscopic colorectal surgery is equal in terms of safety to open surgery. Benefits have been seen for length of stay, blood loss, immune suppression and analgesia requirements. The aim of this study was to assess the safety and feasibility of introducing laparoscopic colorectal surgery to our unit. PATIENTS AND METHODS Prospectively collected cases of all patients undergoing laparoscopic colorectal surgery between July 2003 and July 2007 were reviewed. RESULTS A total of 143 patients (75 males and 68 females) with amean age of 65.8 years (range, 21–95 years) underwent surgery. Laparoscopic resection for colorectal malignancy was performed in 93 patients (65%). The conversion rate for all cases was 14.7%. Mean operative time was 203 min (range, 100–400 min), with amean blood loss of 180 ml. The mean number of lymph nodes in malignant cases was 13.8 with clear resection margin in all but one case. The mean postoperative stay was 5.6 days (median, 4 days; range, 2–35 days). UKCCR standard for lymph node retrieval was achieved in 62.6% of cases. There were four postoperative deaths. The overall 30-day morbidity rate was 21.7%. The service is consultant-led with 9.8% of cases performed by senior trainees and 37% of procedures performed by two consultants. CONCLUSIONS Laparoscopic colorectal surgery is technically feasible and safe in our hands. Although operative time is longer, this is counterbalanced by shorter hospital stay. The results from this series support the findings of others and continuing development of this service.
The Cost of Shoulder Arthroscopy: A Comparison with National Tariff
Authors: Hearnden Anthony , Tennent Duncan 
Published: October 2008

INTRODUCTION ‘Payment by results’ was introduced with the aim of providing each trust with a transparent and fair remuneration for the work done. Hospitals are paid a tariff for each Healthcare Resource Group (HRG). The tariff is calculated at a national level, by means of a complex manipulation of historic financial data. However, the financial viability of a hospital relies on these payments and so accuracy is vital. PATIENTS AND METHODS We conducted a cost analysis of shoulder arthroscopic procedures carried out at an elective orthopaedic unit. This unit is self contained and well audited, providing an unique opportunity to make a more accurate cost analysis. We calculated the cost of the facility, consumables/implants, anaesthetics and staff pay. This was then compared with the amount paid to the trust. RESULTS All arthroscopic operations performed at our institution attract a tariff of £1780. Our cost of a subacromial decompression was £1307, a profit of £473. A rotator cuff repair was £2672, a loss of £892. CONCLUSIONS The tariff is inaccurate. The arthroscopic HRG is too general and fails to address the extra time and expense of equipment some procedures utilise. We found cost was very sensitive to length of operation. Delays and even teaching can make a ‘profitable operation’ lose money for the trust.