bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing computer skills in Tanzanian medical students: an elective experience
Authors: Samuel Miriam , Coombes John C , Miranda J Jaime , Melvin Rob , Young Eoin JW , Azarmina Pejman 
Published: August 2004

Abstract
Background
One estimate suggests that by 2010 more than 30% of a physician's time will be spent using information technology tools. The aim of this study is to assess the information and communication technologies (ICT) skills of medical students in Tanzania. We also report a pilot intervention of peer mentoring training in ICT by medical students from the UK tutoring students in Tanzania.

Methods
Design: Cross sectional study and pilot intervention study. Participants: Fourth year medical students (n = 92) attending Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania. Main outcome measures: Self-reported assessment of competence on ICT-related topics and ability to perform specific ICT tasks. Further information related to frequency of computer use (hours per week), years of computer use, reasons for use and access to computers. Skills at specific tasks were reassessed for 12 students following 4 to 6 hours of peer mentoring training.

Results
The highest levels of competence in generic ICT areas were for email, Internet and file management. For other skills such as word processing most respondents reported low levels of competence. The abilities to perform specific ICT skills were low – less than 60% of the participants were able to perform the core specific skills assessed. A period of approximately 5 hours of peer mentoring training produced an approximate doubling of competence scores for these skills.

Conclusion
Our study has found a low level of ability to use ICT facilities among medical students in a leading university in sub-Saharan Africa. A pilot scheme utilising UK elective students to tutor basic skills showed potential. Attention is required to develop interventions that can improve ICT skills, as well as computer access, in order to bridge the digital divide.
The solution structure of ChaB, a putative membrane ion antiporter regulator from Escherichia coli
Authors: Osborne Michael J , Siddiqui Nadeem , Iannuzzi Pietro , Gehring Kalle 
Published: August 2004

Abstract
Background
ChaB is a putative regulator of ChaA, a Na+/H+ antiporter that also has Ca+/H+ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy.

Results
The structure of ChaB is composed of 3 α-helices and a small sheet that pack tightly to form a fold that is found in the cyclin-box family of proteins.

Conclusion
ChaB is distinguished from its putative DNA binding sequence homologues by a highly charged flexible loop region that has weak affinity to Mg2+ and Ca2+ divalent metal ions.
Heat shock protein 70 expression, keratin phosphorylation and Mallory body formation in hepatocytes from griseofulvin-intoxicated mice
Authors: Fausther Michel , Villeneuve Louis , Cadrin Monique 
Published: August 2004

Abstract
Background
Keratins are members of the intermediate filaments (IFs) proteins, which constitute one of the three major cytoskeletal protein families. In hepatocytes, keratin 8 and 18 (K8/18) are believed to play a protective role against mechanical and toxic stress. Post-translational modifications such as phosphorylation and glycosylation are thought to modulate K8/18 functions. Treatment of mouse with a diet containing griseofulvin (GF) induces, in hepatocytes, modifications in organization, expression and phosphorylation of K8/18 IFs and leads, on the long term, to the formation of K8/18 containing aggregates morphologically and biochemically identical to Mallory bodies present in a number of human liver diseases. The aim of the present study was to investigate the relationship between the level and localization of the stress inducible heat shock protein 70 kDa (HSP70i) and the level and localization of K8/18 phosphorylation in the liver of GF-intoxicated mice. The role of these processes in Mallory body formation was studied, too. The experiment was carried out parallely on two different mouse strains, C3H and FVB/n.

Results
GF-treatment induced an increase in HSP70i expression and K8 phosphorylation on serines 79 (K8 S79), 436 (K8 S436), and K18 phosphorylation on serine 33 (K18 S33) as determined by Western blotting. Using immunofluorescence staining, we showed that after treatment, HSP70i was present in all hepatocytes. However, phosphorylated K8 S79 (K8 pS79) and K8 S436 (K8 pS436) were observed only in groups of hepatocytes or in isolated hepatocytes. K18 pS33 was increased in all hepatocytes. HSP70i colocalized with MBs containing phosphorylated K8/18. Phophorylation of K8 S79 was observed in C3H mice MBs but was not present in FVB/n MBs.

Conclusions
Our results indicate that GF intoxication represents a stress condition affecting all hepatocytes, whereas induction of K8/18 phosphorylation is not occurring in every hepatocyte. We conclude that, in vivo, there is no direct relationship between GF-induced stress and K8/18 phosphorylation on the studied sites. The K8/18 phosphorylation pattern indicates that different cell signaling pathways are activated in subpopulations of hepatocytes. Moreover, our results demonstrate that, in distinct genetic backgrounds, the induction of K8/18 phosphorylation can be different.
Regulatory role of E-NTPase/E-NTPDase in Ca2+/Mg2+ transport via gated channel
Authors: Schreiber Hans M , Kannan Subburaj 
Published: August 2004

Abstract
Background
E-NTPase/E-NTPDase is activated by millimolar concentrations of Ca2+ or Mg2+ with a pH optimum of 7.5 for the hydrolysis of extracellular NTP and NDP. It has been generally accepted that E-NTPase/E-NTPDase plays regulatory role in purinergic signalling, but other functions may yet be discovered.

Results
In this article it is proposed on the basis of published data that E-NTPase/E-NTPDase could play a role in the influx and efflux of Ca2+and Mg2+ in vivo.

Conclusions
Attenuation of extracellular Ca2+ influx by rat cardiac sarcoplasmic anti-E-NTPase antibodies and oligomerization studies on mammalian CD39 conclusively point towards the existence of a new channel in the membrane. Further studies on these properties of the E-NTPase/E-NTPDase may provide detailed mechanisms and identify the potential patho-physiological significance.
A prospective study of conditions associated with multiple sclerosis in a cohort of 658 consecutive outpatients attending a multiple sclerosis clinic
Authors: Edwards L J , Constantinescu C S 
Published: August 2004

The cause of multiple sclerosis (MS) remains unknown. It is largely regarded as being an inflammatory autoimmune disease and has been reported in association with other inflammatory/autoimmune diseases. We performed a prospective study in 658 consecutive patients diagnosed with MS attending our outpatient MS management clinic between June 2002 and June 2003. Prevalence of associated conditions in these patients was calculated and compared with values from population studies using chi-square tests, odds ratios and confidence intervals. The MS population had significantly increased rates of asthma, inflammatory bowel disease, type I diabetes mellitus, pernicious anaemia, autoimmune thyroid disease, uveitis, seronegative spondyloarthropathies, bipolar disorder and melanoma compared to the general population. Both T helper type 1 (Th1)-mediated and T helper type 2 (Th2)-mediated diseases were significantly increased compared to the general population. There were also interesting associations seen with polyglandular autoimmune syndrome and rare single case associations. MS is associated with several other conditions. This work does not give evidence for the hypothesis that MS and atopy, reflecting Th1 and Th2 polarization, respectively, are mutually exclusive. Further work, ideally with a matched control population, is indicated.
Allogeneic Lymphocytes Induce Tumor Regression of Advanced Metastatic Breast Cancer
Authors: Bishop Michael R. , Fowler Daniel H. , Marchigiani Donna , Castro Kathleen , Kasten-Sportes Claude , Steinberg Seth M. , Gea-Banacloche Juan C. , Dean Robert , Chow Catherine K. , Carter Charles , Read Elizabeth J. , Leitman Susan , Gress Ronald 
Published: August 2004

Purpose Allogeneic T lymphocytes can induce regression of metastatic breast cancer through an immune-mediated graft-versus-tumor (GVT) effect in murine models. To determine if a clinical GVT effect exists against metastatic breast cancer, allogeneic lymphocytes were used as adoptive cellular therapy after a reduced-intensity chemotherapy conditioning regimen and allogeneic hematopoietic stem-cell transplantation (HSCT) from human leukocyte antigen–matched siblings. Patients and Methods Sixteen patients with metastatic breast cancer that had progressed after treatment with anthracyclines, taxanes, hormonal agents, and trastuzumab, received allogeneic HSCT. The reduced-intensity transplant conditioning regimen consisted of cyclophosphamide and fludarabine. To distinguish an immunological GVT effect from any antitumor effect of cytotoxic chemotherapy in the transplant-conditioning regimen, allogeneic T lymphocytes were removed from the stem-cell graft and were subsequently administered late postallogeneic HSCT. Allogeneic lymphocytes containing 1 × 106, 5 × 106, and 10 × 106 CD3+ cells/kg were infused on days +42, +70, and +98 post–allogeneic HSCT, respectively. Results Objective tumor regressions occurred after day +28 post–allogeneic HSCT in six patients and were attributed to allogeneic lymphocyte infusions. Two of these responding patients had disease progression post–allogeneic HSCT before subsequent tumor regression. Tumor regressions occurred concomitantly with the establishment of complete donor T-lymphoid engraftment, were associated with the development of graft-versus-host disease (GVHD), and were abrogated by subsequent systemic immunosuppression for GVHD. Conclusion Allogeneic lymphocytes can induce regression of advanced metastatic breast cancer. These results indicate that an immunological GVT effect from allogeneic lymphocytes exists against metastatic breast cancer and provide rationale for further development of allogeneic cellular therapy for this largely incurable disease.
Gamma Knife Radiosurgery for Pituitary Adenoma: Early Results
Authors: Petrovich Zbigniew , Yu Cheng , Giannotta Steven L. , Zee Chi-Shing , Apuzzo Michael L.J. 
Published: August 2004

Abstract

OBJECTIVE
In recent years, gamma knife radiosurgery (GKRS) has emerged as an important treatment modality in the management of pituitary adenomas. Treatment results after performing GKRS and the complications of this procedure are reviewed.

METHODS
Between 1994 and 2002, a total of 78 patients with pituitary adenomas underwent a total of 84 GKRS procedures in our medical center. This patient group comprised 46 men (59%) and 32 women (41%). All patients were treated for recurrent or residual disease after surgery or radiotherapy, with 83% presenting with extensive tumor involvement. The cavernous sinus was involved in 75 patients (96%), and 22 patients (28%) had hormone-secreting adenomas. This latter subset of patients included 12 prolactinomas (15%), 6 growth-hormone secreting tumors (8%), and 4 adrenocorticotropic hormone-secreting tumors (5%). The median tumor volume was 2.3 cm3, and the median radiation dose was 15 Gy defined to the 50% isodose line. The mean and median follow-up periods were 41 and 36 months, respectively.

RESULTS
GKRS was tolerated well in these patients; acute toxicity was uncommon and of no clinical significance. Late toxicity was noted in three patients (4%) and consisted of VIth cranial nerve palsy. In two patients, there was spontaneous resolution of this palsy, and in one patient, it persisted for the entire 3-year duration of follow-up. Of the 15 patients who presented with cranial nerve dysfunction, 8 (53%) experienced complete recovery and 3 (20%) showed major improvement within 12 months of therapy. Tumor volume reduction was slow, with 30% of patients showing decreased tumor volume more than 3 years after undergoing GKRS. None of the 56 patients with nonfunctioning tumors showed progression in the treated volume, and 4 (18%) of the 22 hormone-secreting tumors relapsed (P = 0.008). Of the four patients with adrenocorticotropic hormone-secreting adenomas, therapy failed in two of them. All six patients with growth hormone-producing tumors responded well to therapy. Of the 12 patients with prolactinomas 10 (83%) had normalization of hormone level and 2 patients experienced increasing prolactin level. Two patients with prolactinomas had three normal pregnancies after undergoing GKRS.

CONCLUSION
GKRS is a safe and effective therapy in selected patients with pituitary adenomas. None of the patients in our study experienced injury to the optic apparatus. A radiation dose higher than 15 Gy is probably needed to improve control of hormone-secreting adenomas. Longer follow-up is required for a more complete assessment of late toxicity and treatment efficacy.
Limited Benefit of Intraoperative Low-field Magnetic Resonance Imaging in Craniopharyngioma Surgery
Authors: Nimsky Christopher , Ganslandt Oliver , Hofmann Bernd , Fahlbusch Rudolf 
Published: August 2004

Abstract

OBJECTIVE
To investigate the benefit of intraoperative low-field magnetic resonance imaging (MRI) in craniopharyngioma surgery.

METHODS
We used a 0.2-T Magnetom Open scanner (Siemens Medical Solutions, Erlangen, Germany) that was located in a radiofrequency-shielded operating theater for intraoperative MRI. The head of the patient was placed in the fringe field of the scanner, so that standard microinstruments could be used. In transsphenoidal surgery, T1-weighted coronal and sagittal images were acquired. In transcranial surgery, a three-dimensional, gradient echo, T1-weighted, fast low-angle shot sequence was measured, thus allowing multiplanar reformatting.

RESULTS
A total of 21 surgical procedures in craniopharyngioma patients were investigated. In 10 patients, a bifrontal-translaminar approach was used; in 6 patients, the craniopharyngioma was removed via a transsphenoidal approach; and in 5 patients, intraoperative MRI was used to monitor cyst puncture and aspiration. In the craniotomy group, intraoperative imaging depicted a clear tumor remnant in one patient, which was subsequently removed. In another patient, an area of contrast enhancement was interpreted as artifact; however, postoperative follow-up at 3 months was suspicious for a minor remnant. Two of the eight patients with complete removal developed a recurrence during the follow-up period. In the group of patients who underwent primary transsphenoidal surgery (n = 4), complete removal was estimated by the surgeon in three cases. Intraoperative imaging depicted a remaining tumor in one case, leading to further tumor removal; however, follow-up revealed recurrent cysts.

CONCLUSION
Intraoperative low-field MRI allows an ultraearly evaluation of the extent of tumor removal in craniopharyngioma surgery in most cases. Imaging showing an incomplete resection offers the chance for further tumor removal during the same operation. However, intraoperative low-field MRI depicting a complete resection does not exclude craniopharyngioma recurrence.
The Natural History of Incidental Meningiomas
Authors: Nakamura Makoto , Roser Florian , Michel Julia , Jacobs Cornelius , Samii Madjid 
Published: August 2004

Abstract

OBJECTIVE
Little information about the natural history of incidental meningiomas exists in the literature. The aim of this study was to determine the natural history of asymptomatic meningiomas by comparing different methods of growth rate calculation to establish a strategy for dealing with these tumors.

METHODS
In 47 asymptomatic patients, hospital charts, follow-up records, and imaging studies were reviewed. Of these patients, 6 underwent surgery. Tumor growth rates were determined by calculating the absolute and relative growth rates and the tumor volume doubling times.

RESULTS
In 41 patients with conservative management, the average tumor size was 9 cm3, and the majority (66%) of growth rates were less than 1 cm3/yr. The absolute growth rate ranged from 0.03 to 2.62 cm3/yr (mean, 0.796 cm3/yr). Relative annual growth rates ranged from 0.48 to 72.8% (mean, 14.6%). The tumor doubling time ranged from 1.27 to 143.5 years (mean, 21.6 yr). A moderate correlation between the age and growth rates was found. In young patients, annual growth rates tended to be higher and tumor doubling times shorter. There was no clear correlation between the initial tumor size and tumor doubling time. The mean annual growth rate of meningiomas with calcification was lower than in tumors without calcification. Also, tumors with hypointense or isointense T2 signals on magnetic resonance imaging had a lower growth rate. In the group of six patients with surgical excision, tumor growth rates were higher and tumor doubling times shorter than in the nonsurgical group.

CONCLUSION
The majority of incidental meningiomas show minimal growth; thus, they may be observed without surgical intervention unless specific symptoms appear. Tumor growth is associated with patient age. The initial tumor size is not considered a predictive factor for tumor growth. Radiological features, such as calcification or T2 signal intensity, may provide useful information to predict the growth potential of meningiomas.
Recombinant Activated Factor VII for the Rapid Correction of Coagulopathy in Nonhemophilic Neurosurgical Patients
Authors: Park Paul , Fewel Matthew E. , Garton Hugh J. , Thompson B. Gregory , Hoff Julian T. 
Published: August 2004

AbstractOBJECTIVECoagulopathy is a significant contraindication for neurosurgery. Unfortunately, many coagulopathic patients require urgent neurosurgical intervention. Standard use of blood products, including fresh-frozen plasma or prothrombin complexes, to correct the coagulopathy often leads to significant delays in treatment. Recombinant activated factor VII (rFVIIa) is a medication originally designed to treat bleeding in hemophiliacs but also seems to correct a wide variety of coagulopathies rapidly and safely in nonhemophilic patients.METHODSThe medical records of nine patients with coagulopathy requiring urgent neurosurgical intervention were reviewed retrospectively. Each patient was given a dose ranging from 40 to 90 μg/kg of rFVIIa before undergoing surgery. Pre-rFVIIa coagulation and post-rFVIIa coagulation parameters were obtained. Once correction of the coagulopathy was verified, each patient underwent the appropriate neurosurgical procedure.RESULTSThe average age of the patients was 40.9 years; six were women. The causes of the coagulopathy included anticoagulant medication, liver dysfunction, and dilutional coagulopathy after traumatic hemorrhage. Neurosurgical indications included intraparenchymal/intraventricular hemorrhage, hydrocephalus, diffuse cerebral edema, and epidural hematoma. Post-rFVIIa coagulation parameters obtained as early as 20 minutes after infusion of the medication showed normalization of values. There were no procedural or operative complications and no postoperative hemorrhagic complications. No associated thromboembolic or other complications with the use of rFVIIa were observed.CONCLUSIONThe use of rFVIIa for the urgent surgical treatment of coagulopathic patients is quite promising. Further studies, including randomized, prospective trials using rFVIIa to address issues such as optimal dosing, efficacy, surgical indications, cost-effectiveness, morbidity, and mortality are needed.
Routine Placement of a Ventricular Reservoir at Endoscopic Third Ventriculostomy
Authors: Aquilina Kristian , Edwards Richard J. , Pople Ian K. 
Published: August 2004

Abstract

OBJECTIVE
Endoscopic third ventriculostomy (ETV) failure may be abrupt in onset, causing a potentially life-threatening increase in intracranial pressure. ETV failure may also have a more insidious onset, and in these cases, diagnosis on clinical and radiological grounds can be difficult. This study evaluates the usefulness of routine ventricular reservoir placement at the time of ETV for subsequent emergency ventricular access or the diagnosis of ETV failure.

METHODS
A retrospective review of 84 consecutive patients undergoing ETV with routine insertion of a ventricular reservoir during a 4-year period (1996–2000) was undertaken. The mean follow-up period was 14.8 months. End points for ETV failure were shunt insertion or revision of ETV. The diagnostic and therapeutic use of the reservoir was quantified.

RESULTS
The reservoir was used in 32% of patients (n = 27). The reservoir allowed life-saving emergency ventricular access in two cases of acute recurrent hydrocephalus. In patients with symptoms but equivocal radiological evidence of recurrent hydrocephalus, the reservoir allowed for assessment of intracranial pressure (n = 19) and/or a therapeutic trial of cerebrospinal fluid aspiration (n = 5). Seven of these patients subsequently required revision ETV or shunt insertion. In the 14 patients who had normal intracranial pressure, conservative management was successful. The reservoir also facilitated intrathecal drug administration for postoperative ventriculitis (n = 2). No patients requested reservoir removal.

CONCLUSION
Routine insertion of a ventricular reservoir allows life-saving emergency therapeutic cerebrospinal fluid aspiration to be performed for sudden neurological deterioration caused by ventriculostomy failure. It also assists in the diagnosis of ETV failure and allows intrathecal drug administration.