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J Weber

Publications and source records attributed to J Weber.

At least 55 records · Page 3Linked to original sources
PubMed2002

[Parasagittal meningioma in a skull dated 32500 years before present from southwestern Germany].

Summary. During excavation in 1931 by Riek in the cave of Vogelherd close to Stetten in the Lone Valley in southwestern Germany there was found an anatomically modern human skull (called: "Stetten 2") dated 32500 years before present. The skull was excavated without postcranial skeleton in the cave and showed no signs of burial. Paleopathological examinations of the calvarium reveals skeletal abnormalities that indicate parasagittal meningioma next to the bregma. Paracentral Meningiomas cause seizures and focal weakness, followed by headache. These observations are discussed in the context of modern medical knowledge. Our theory integrated archaeological, anthropological and paleopathological knowledge and helped to create the understanding of Paleolithic and earliest modern man knew regarding the "brain" and illness.

Germany↗
PubMed2002

Ortho and para interstitial H2 in silicon.

A Raman scattering study of H2 trapped at the interstitial T site in Si is presented. Both ortho and para nuclear-spin states of H2 and D2 have been observed. It is shown that the Raman signals of H2 and D2 in the J=0 state, where J is the rotational quantum number, disappear preferentially from the spectra during laser excitation or prolonged storage at room temperature in the dark. This surprising behavior is tentatively explained by different diffusion rates of H2 in the J=0 and J=1 states.

Journal Article↗
PubMed2002

Temozolomide and whole brain irradiation in melanoma metastatic to the brain: a phase II trial of the Cytokine Working Group.

PURPOSE: To evaluate the antitumor effects and toxicities of whole brain irradiation (WBI) with temozolomide (TMZ) administered by prolonged oral dosing in patients with melanoma metastatic to the brain. BACKGROUND: Patients with melanoma metastatic to the central nervous system (CNS) have an extremely poor prognosis and appear to benefit little from WBI. TMZ is an alkylating agent chemically similar to dacarbazine (DTIC) with good oral bioavailability and CNS penetration. TMZ has broad preclinical antitumor activity which in melanoma is comparable to that of DTIC. The combination of TMZ and WBI may provide enhanced antitumor activity against CNS metastasis from melanoma. PATIENTS AND METHODS: Patients with measurable CNS metastases with or without systemic disease were treated with WBI, 30 Gray over ten fractions (days 1-5 and 8-12). TMZ, 75 mg small middle dotm(2 small middle dot)day, was started on day 1, continued daily for 6 weeks and repeated every 10 weeks. RESULTS: Thirty-one patients were treated. There was one CNS complete response of 4.5 months and two CNS partial responses of 2 months and 7 months duration; the latter patient also had a 4-month complete remission of systemic metastases. Toxicities were limited to a single episode of grade 3 transaminase elevation and two episodes of grade 3 neutropenia, one complicated by fatal sepsis. The median progression-free interval for both CNS and extracranial sites was 2 months (range 1 week-11 months), and median survival 6 months (range 2-12 months). CONCLUSIONS: WBI has lower than expected activity in CNS metastasis of malignant melanoma. Although TMZ can be safely administered with WBI, the combination has limited anti-tumor activity.

Administration, Oral↗
PubMed2002

MRI atlas of the human cerebellar nuclei.

The differential role of the cerebellar cortex and nuclei has rarely been addressed in human lesion and functional brain imaging studies. One important reason is the difficulty of defining the localization of the cerebellar nuclei and extent of possible lesions based on CT or MR scans. The present MRI investigation was specifically designed to study the anatomy of the deep cerebellar nuclei. In both basal ganglia and cerebellar nuclei of healthy human subjects the amount of iron is high compared to the rest of the brain. Clusters of iron are paramagnetic and, therefore, tend to cause local inhomogenities in a magnetic field. The iron-induced susceptibility artefacts were used to visualize the cerebellar nuclei as hypointensities on MR images. A three-dimensional atlas of the dentate (D), interposed (I), and fastigial (F) nuclei is presented in standard proportional stereotaxic space coordinates based on findings in a healthy 26-year-old female. A three-dimensional axial volume of the cerebellum was acquired using a T1-weighted fast low-angle shot (FLASH) sequence on a Siemens Sonata 1.5 Tesla MR. To increase the signal to noise ratio the sequence was acquired 5 times and averaged. Each volume was registered, resampled to 1.00 x 1.00 x 1.00-mm3 voxel size and spatially normalized into a standard proportional stereotaxic space (the MNI-space) using SPM99. Localization of cerebellar nuclei were confirmed by comparison with postmortem MRI and histological microsections of another brain.

Adult↗
PubMed2002

[Improving productivity by implementing RIS and PACS throughout the clinic: a case study].

PROBLEM: How are improvements in productivity in connection with RIS/PACS to be defined? What do they cost? To limit the problem to the relevant topics, we first describe the objectives of a radiology department and the identified bottlenecks in the workflow. How to define and assess the improvements is discussed. METHODS: The case in question for this study is the RIS/PACS project at the "Klinikum der Universität München, Campus Grosshadern". The goals of the project and its present status are reviewed. The project is not yet completed, so this is a "midterm" report. RESULTS AND DISCUSSION: We describe the status of the achieved and not yet achieved goals and of the eliminated bottlenecks. On the plus side, for example, nearly 100% of all digitally generated images (except mammogramms) are digitally archived. They are accessible to the same percentage in radiology via PACS and in the hospital via the webbased intranet image distribution system when needed. In some radiology areas, such as multislice CT, already the reporting can no longer be performed without softcopy image interpretation. However, the full elimination of hardcopy images is still not reality, since the distribution to DICOM viewers for selected requesters with demands for almost reporting quality, high cost image displays is still in the testphase. To reduce film costs, images are being printed on a high resolution paper printer in addition to the intranet distribution during this transition period. On the negative side, due to a lack of job positions in the transcription rooms, about 40% of the reports are still being handwritten by radiologists. Furthermore, the dictated and transcribed reports are usually still not available early enough in the RIS and thereby in the intranet report distribution of the hospital. Here only a speech recognition system can remedy the situation. As soon as this problem is solved and the image distribution to the DICOM viewers works routinely, the reports and the images will be accessible within minutes to maximally within some hours after the examination. CONCLUSION: The goals reached so far suffered delays due to unforeseen problems and pitfalls. Altogether, a quieter operation and workflow in radiology has already been achieved, due to less inquiries from the requestors for unfinished examinations, images and/or image copies.

Computer Systems↗
PubMed2002

Experimental studies and first clinical experience with a new Lithoclast and ultrasound combination for lithotripsy.

OBJECTIVES: A new lithotriptor for intracorporeal lithotripsy was developed combining the two most effective lithotriptors. A combination of the mechanically driven Lithoclast Master and a new ultrasonic device was constructed. Efficacy was tested in standardized model stones and in patient treatment. MATERIAL: The new lithotriptor is composed of a Lithoclast Master and an ultrasonic device (EMS, Nyon, Switzerland). The 1.0 mm Lithoclast probe is advanced off-center through the hollow 3.3 mm ultrasonic probe and protrudes about 1 mm. Five different artificial stones of defined hardness and density were used as model stones for disintegration. Time until first fragmentation and complete fragmentation (particles smaller than 2.2 mm to fit through the ultrasonic probe), percent disintegration after 1 min and time until 50% disintegration were determined for the new device as well as lithoclast and ultrasound alone. A total of 68 patients were treated by percutaneous nephrolitholapaxy (PNL) with the new device from February 1999 to August 2001. Lithotripsy was performed after fluoroscopically guided puncture of the lower calix and dilatation of the nephrostomy tract with coaxial bougies. Thirty-five patients had complete and 33 patients partial staghorn calculi. RESULTS: First fragmentation was reached 25-200 times faster with the combination as with either mode alone. Disintegrated stone mass after 1 min was 1.5-4 times larger in combined lithotripsy and 50% disintegration time 30-50% shorter. Clinically, complete stone free rate (KUB and ultrasound) was 66% after the first PNL. Sixteen out of 68 patients had a second look PNL with an overall stone free rate of 89.7% by dismission. Stone composition was calcium-oxalate-monohydrate in 13%, Ca-ox-monohydrate/uric acid in 35%, apatite in 20% and cystine in 11%. CONCLUSION: In in vitro experiments and clinically the new lithotriptor provides easy handling and high effectivity in fragmentation of all stones regardless of their composition.

Equipment Design↗
PubMed2002

Clinical experience with a new ultrasonic and LithoClast combination for percutaneous litholapaxy.

OBJECTIVE: To assess a new lithotripter for intracorporal lithotripsy, which combines the mechanically driven pneumatic LithoClast (Electro-Medical Systems, Nyon, Switzerland) and a new ultrasonic device (Electro-Medical Systems), for use in percutaneous nephrolitholapaxy (PNL). PATIENTS AND METHODS: The new lithotripter consists of a LithoClast Master with 12 Hz repetition rate and a new ultrasonic device. The 1.0 mm LithoClast probe is advanced off-centre through the hollow 3.3 mm ultrasonic probe and protrudes about 1 mm. A new irrigation system with a pinch valve compressing the irrigation tube, a foot-switch for activating the ultrasound, the LithoClast and both together, and a stone bucket at the outlet tube are new features. Between February 1999 and August 2001, 68 patients were treated by PNL with the new device; 35 had complete and 33 had partial staghorn calculi. PNL was administered under fluoroscopic control and with the patient prone. RESULTS: The mean (range) duration of surgery was 61 (42-119) min. The complete stone-free rate was 66% after the first PNL; of the 68 patients, 16 received a second PNL, giving a final stone-free rate of 76% and 80%. The stone was composed of calcium oxalate monohydrate (COM) in 13%, COM with uric acid in 35%, apatite in 20% and cystine in 11%. Clinically the new lithotripter was very effective, producing smaller stone particles and thus fewer residual stone fragments after PNL than with the LithoClast or ultrasonic fragmentation alone. CONCLUSION: The new lithotripter provides easily managed and highly effective stone fragmentation of all stones, regardless of their composition.

Equipment Design↗
PubMed2002

Effect of mandibular orthopedic repositioning appliance on kinematic pattern in golf swing.

Experience has shown that repositioning the mandible may have an influence on the athletic performance. Many athletes with or without occlusal problems are now using mandibular orthopedic repositioning appliance (MORA) supposedly to optimize their performance. In golf, the players do not have any direct opponent and they have different clubs to reach various distances. Therefore, an automatic swing permits the uncertainty of the movement to be restricted. The aim of this study was to analyze if the use of the MORA could have an effect on the stability of the kinematic pattern in golf swing, connected to the capacity of the golfers to reproduce their swing from kinematic perspective. The measures of kinematic data have been established with the optoelectronic system VICON (Oxford's Metrix, Oxford, UK) with five cameras operating at 50 frames per second. Measurements of the speed of the ball at impact were obtained with a radar (Bridgestone HD.01, Science eye, USA). Six professional (current handicap ranging from 0 to 4) right-handed golfers participated in the study. Six MORA were made and adjusted to fit each player. Each golfer performed five swings without mouthpiece and five with the MORA. The results of this study show that there was no difference related to the MORA on kinematic pattern of the golf swing. Moreover, there were significant differences concerning the ball speed at the impact, among the two test conditions, with or without the appliance (p < 0.03). The percentage of variability indicates that the speed with MORA was more regular than the speed without the appliance.

Adolescent↗
PubMed2002

Angiographic cerebral vasospasm and delayed ischemic deficit on anterior part of the circle of Willis. Usefulness of transcranial Doppler.

BACKGROUND AND PURPOSE: After subarachnoid hemorrhage (SAH), cerebral vasospasm (VS) may be revealed by cerebral angiography, during follow-up clinical examination with the occurrence of delayed ischemic deficit (DID). Moreover, transcranial Doppler (TCD) could be useful in determining the level of the velocimetric threshold. The aims of the study were, on a prospectively collected series of 460 patients, to assess angiographic VS incidence, to determine possible risk factors, and to evaluate diagnostic sensitivity and specificity of TCD. PATIENTS AND METHOD: A total of 460 patients consecutively operated on for an aneurysm located on the anterior portion of the circle of Willis (mean age 47.2 +/- 14 years, sex ratio F/M=1.18) were included in the study. Preventive treatment against VS was administered in all patients. On the 10(th) day, we performed the following routine examinations: cerebral angiography, CT scan and TCD. RESULTS: Angiographic VS occurred in 38.5% of the patients, and the single risk factor was delayed admission (p=0.02, Mann-Whitney test). DID occurred in 15.6% and was complicated by cerebral infarct in 4.7%. The risk factors were admission date (p=0.001, Mann-Whitney test) and severity of arterial narrowing (significant tendency). Diagnostic sensitivity of TCD decreased from 83.6% for MCA aneurysms, to 66.6% for ICA aneurysms and 40.6% for AcoA aneurysms. Diagnosis specificity remained between 88.6% and 97.6% for the 3 locations. CONCLUSION: The unique risk factor for angiographic VS and DID was the admission date. TCD demonstrated high specificity but its sensitivity was too low for the aneurysms located far from the middle cerebral artery bifurcation.

Albumins↗
PubMed2002

A preliminary study to assess a French code of ethics for health teaching resources on the Internet.

BACKGROUND: Constant assessment of the quality of health information on the Internet is an absolute necessity as peer review is often lacking in this media. OBJECTIVE: To develop a simple and easy French Code of Ethics, which will enable medical students to judge quality of health information in teaching material available on the Internet. DESIGN: Three medical informaticians selected ten criteria from previously established codes of ethics from Europe and the USA. This instrument was tested on a sample of 30 health Internet teaching resources. RESULTS: For the panel of experts, chance corrected inter-observer agreement (kappa) for quality rating ranged from k = -0.19 and k = 0.33, demonstrating poor agreement among the raters. CONCLUSION: If negative results of this preliminary study are confirmed by further research, this finding may detrimentally affect projects in Europe to accredit or certify Internet health resources.

Codes of Ethics↗
PubMed2001

Photochemistry of the CpNiNO complex. A theoretical study using density functional theory.

The photochemistry of the CpNiNO complex has been investigated using density functional theory. The whole potential energy curve along the NiNO angle coordinate is presented for the first time with both ground and metastable states, and transition states connecting the minima. The excited states of the GS, MS(I), and MS(II) species have been calculated using time-dependent density functional theory. Furthermore, the structure of the excited states pertaining to the photochemistry of CpNiNO has been optimized. From these results it is shown that the backward GS <-- MS(II) <-- MS(I) reaction is more efficient than the forward GS --> MS(II) --> MS(I) scheme.

Journal Article↗
PubMed2001

How important is the 'quality' of the cytotoxic T lymphocyte (CTL) response in protection against HIV infection?

Cytotoxic T lymphocyte (CTL) responses have been associated with protection from HIV-1 infection in people with a high degree of exposure to HIV and who show no serological evidence of HIV infection (HEPS, highly exposed persistently seronegative). However, it remains unclear how protective CTL responses could apparently develop in a minority of people, whilst the great majority of HIV-infected people make strong CTL responses yet progress to AIDS and death. In this paper we review the data which supports the hypothesis that the quality of the T-cell response, rather than its magnitude, may be an important factor that merits further investigation.

CD4-Positive T-Lymphocytes↗
PubMed2001

Similar turnover and shedding of the cellular prion protein in primary lymphoid and neuronal cells.

The cellular prion protein (PrP(C)) is essential for pathogenesis and transmission of prion diseases. Although prion replication in the brain is accompanied by neurodegeneration, prions multiply efficiently in the lymphoreticular system without any detectable pathology. We have used pulse-chase metabolic radiolabeling experiments to investigate the turnover and processing of PrP(C) in primary cell cultures derived from lymphoid and nervous tissues. Similar kinetics of PrP(C) degradation were observed in these tissues. This indicates that the differences between these two organs with respect to their capacity to replicate prions is not due to differences in the turnover of PrP(C). Substantial amounts of a soluble form of PrP that lacks the glycolipid anchor appeared in the medium of splenocytes and cerebellar granule cells. Soluble PrP was detected in murine and human serum, suggesting that it might be of physiological relevance.

Animals↗
PubMed2001

Effects of interleukin-12 on the immune response to a multipeptide vaccine for resected metastatic melanoma.

PURPOSE: Forty-eight patients with high-risk re-sected stage III or IV melanoma were immunized with two tumor antigen epitope peptides derived from gp100(209-217)(210M) (IMDQVPSFV) and tyrosinase(368-376)(370D) (YMDGTMSQV) emulsified with incomplete Freund's adjuvant (IFA). Patients received peptides/IFA with or without interleukin (IL)-12 30 ng/kg to evaluate the toxicities and immune responses in either arm with time to relapse and survival as secondary end points. PATIENTS AND METHODS: Immunizations were administered every 2 weeks for 8 weeks, then every 4 weeks for 12 weeks, and then once 8 weeks later. A leukapheresis to obtain peripheral-blood mononuclear cells for immune analyses was done before and after vaccination. Skin testing with peptides and recall reagents was performed before and after vaccinations. RESULTS: Local pain and granuloma formation, fever, and lethargy of grade 1 or 2 were observed. Transient vaccine-related grade 3-but no grade 4-toxicity was observed. Thirty-four of 40 patients developed a positive skin test response to the gp100 peptide but none to tyrosinase. Immune responses were measured by release of gamma-interferon in an enzyme-linked immunosorbent assay (ELISA) by effector cells in the presence of peptide-pulsed antigen-presenting cells or by an antigen-specific tetramer flow cytometry assay. Thirty-three of 38 patients demonstrated an immune response by ELISA after vaccination, as did 37 of 42 patients by tetramer assay. Twenty-four of 48 patients relapsed with a median follow-up of 20 months, and 10 patients in this high-risk group have died. CONCLUSION: These data suggest a significant proportion of patients with resected melanoma mount an antigen-specific immune response against a peptide vaccine and indicate that IL-12 may increase the immune response and supporting further development of IL-12 as a vaccine adjuvant.

Adolescent↗
PubMed2001

'Chemical condoms' for the prevention of HIV infection: evaluation of novel agents against SHIV(89.6PD) in vitro and in vivo.

BACKGROUND: Vaginal agents which are antiviral and/or inhibit the entry of HIV into the cell could prevent heterosexual transmission of HIV, and protect women who cannot negotiate condom use. METHODS: Four agents have been investigated for activity in vitro and in vivo against SHIV(89.6PD): two anionic polymers, dextrin-2-sulphate (D2S) and PRO 2000 (P2K), and two virucidal agents; a non-ionic detergent, nonoxynol-9 (N9) and a cyclic peptide ionophore, gramicidin-D (GD). All four agents were investigated in rhesus macaques, using an intra-vaginal challenge of two inoculations of 1 x 104 50% tissue culture infectious doses (TCID)50 of SHIV(89.6PD). RESULTS: D2S, P2K, GD and N9 all inhibited SHIV(89.6PD) in vitro. In vivo, three out of four control macaques were infected as judged by viral culture, seroconversion, DNA and RNA PCR; infection was confirmed in four out of eight macaques pre-treated with P2K, two out of four pre-treated with D2S, one out of four pre-treated with N9, two out of four pre-treated with GD and four out of four pre-treated with D2S + GD, a combination additive in vitro. INTERPRETATION: D2S and PRO-2000, novel inhibitors of HIV entry, showed evidence of protection in vivo, comparable to that seen with the virucide, N9. These data, together with the results of phase I and phase II studies in healthy women which have shown minimal toxicity, support plans for a phase III efficacy trial of chemically simple inhibitors of HIV entry with low toxicity, for the prevention of HIV infection in women.

Administration, Intravaginal↗
PubMed2001

[Spontaneous intraspinal epidural hematoma secondary to use of platelet aggregation inhibitors].

HISTORY AND ADMISSION FINDINGS: A 64-year-old woman previously in good health experienced an acute onset of severe neck pain and weakness of the left arm that had developed within minutes. Neurological examination revealed paresis of the left arm. There was a previous history of cardiovascular disease and she had been treated with 100 mg of aspirin per day. INVESTIGATIONS: MRI revealed a left posterolateral intraspinal mass extending from C3 to C7. The hemostatic evaluation showed no abnormalities (platelet count, prothrombin time, partial thromboplastin time). TREATMENT AND COURSE: A laminectomy with evacuation of the epidural hematoma was performed. The postoperative course was uneventful, with complete disappearance of the neurological deficit. CONCLUSION: We report a rare condition of spontaneous spinal epidural hematoma that was associated with aspirin intake. A short time interval from onset of symptoms to diagnosis (MRI) and surgery is crucial for the outcome.

Angina Pectoris↗