Search PubMed⌕ Search

Biomedical subjects

A Steiner

Publications and source records attributed to A Steiner.

At least 19 recordsLinked to original sources
PubMed1998

Implantation of a reinforced polytetrafluoroethylene vascular graft for treatment of obstructions of the teat and mammary gland cisternae in cattle.

OBJECTIVE: To evaluate use of an artificial vascular graft as treatment for obstructions of the teat and mammary gland cisternae in lactating cattle. DESIGN: Prospective clinical study. ANIMALS: 14 lactating dairy cows. PROCEDURE: After physical examination that included palpation, ultrasonography, evaluation of milk flow, and California mastitis test, each cow underwent surgical excision of obstructive tissue and implantation of a reinforced polytetrafluoroethylene vascular graft. Milk drained passively for 10 to 14 days after surgery. Follow-up evaluation was performed by telephone questionnaire of owners 1, 6, and 12 months after surgery regarding somatic cell count, time needed to milk affected quarter, compared with that of the contralateral quarter, and frequency of mastitis. After the subsequent nonlactation period and calving, milk flow was tested, using a quarter milking machine, and ultrasonographic examination of the affected teat was performed. RESULTS: Milk could be obtained from affected quarters from all cows 14 days after surgery, from 13 (93%) cows 1 month after surgery, from 10 (71%) cows 6 months after surgery, and from 3 (21%) cows 12 months after surgery, but milk flow in these 3 cows was considerably reduced. This technique failed because of collapse of the implant (4 cows), chronic mastitis (1), migration of the implant (4), and ingrowth of obstructive tissue between the distal aspect of the implant and the ridges of mucous membrane that radiate from the internal orifice of the streak canal (4), or a combination of these. CLINICAL IMPLICATIONS: Implantation of this vascular graft is a useful technique to restore teat patency for 6 months. A longer period of passive drainage of milk appears necessary for sufficient ingrowth of the graft. Lesions that extend to the distal most aspect of the teat cistern have a poor prognosis, because this area cannot be sufficiently overlapped by the graft.

Animals↗
PubMed1998

Treatment of infectious arthritis of the radiocarpal joint of cattle with gentamicin-impregnated collagen sponges.

Gentamicin-impregnated collagen sponges were used successfully in the treatment of chronic septic arthritis of the radiocarpal joint in two cattle. Both animals were moderately to severely lame and refractory to systemic antibiotics, and one of them was refractory to joint lavage and local antibiotics. The clinical diagnosis was confirmed by radiography and arthrocentesis. Arthroscopy was performed under general anaesthesia and, after debridement and lavage of the joint, gentamicin-impregnated collagen sponges were placed intra-articularly. Synovial fluid was sampled at 10 and 20 days after surgery and radiographs were taken three months (case 1) and two months (case 2) after surgery. The infection was eliminated from both animals and they recovered without residual lameness.

Animals↗
PubMed1998

Molecular and functional characteristics of MAP-2a: ability of MAP-2a versus MAP-2b to induce stable microtubules in COS cells.

Microtubule-associated protein-2 (MAP-2) is a prominent cytoskeletal protein in the mammalian nervous system. Two high-molecular-weight (HMW) MAP-2 isoforms, MAP-2a and MAP-2b, are developmentally regulated. MAP-2b is expressed through the life of the neuron, while MAP-2a expression coincides with the time of synaptic formation. MAP-2a and MAP-2b differ in size by approximately 10 kD. Attempts to differentiate MAP-2a from MAP-2b led to the identification of additional exons; exons 7A, 8, 13, and 16. The focus of the present study was to define the complete molecular composition of MAP-2a that was prerequisite for investigating the functional characteristic of the MAP-2a protein. Detailed examination of rat brain mRNA by Northern blot analysis and RT-PCR showed that MAP-2a contains only exon 8 in addition to the exons found in the MAP-2b transcript. Exons 7A, 13, and 16 are not present in the MAP-2a transcript. Antibody generated to exon 8 expressed protein, immunoprecipitated a HMW protein from adult rat brain that co-migrated with MAP-2a and was immunopositive with other MAP-2 antibodies. Comparative transfections of full-length MAP-2a and MAP-2b cDNA into COS-7 cells demonstrated that MAP-2a influenced the microtubule network differently than MAP-2b by inducing rapid and stable microtubule bundle formation even in the presence of nocodazole.

Animals↗
PubMed1998

Acute effects of 10-minute exposure to hydrogen fluoride in rats and derivation of a short-term exposure limit for humans.

A series of acute inhalation exposures of female rats was conducted with hydrogen fluoride (HF) to establish a concentration-response curve for nonlethal exposures. Durations of 2 and 10 min were used to simulate possible short-term exposures. Concentrations of HF ranged from 593 to 8621 ppm for 2-min exposures and from 135 to 1764 ppm for 10-min exposures. Additional exposures were performed for 60 min at 20 and 48 ppm HF for comparison to existing Emergency Response Planning Guidelines. Animals were evaluated on the day after exposure for changes in parameters of bronchoalveolar lavage, pulmonary function, hematology, serum chemistry, body weight, organ weights, and histopathology. Most exposures were performed with orally cannulated animals to bypass absorption of HF in the nose and achieve maximum delivery of HF to the lower airways. One of the primary uses of the resulting data was to estimate a concentration to which most people could be exposed for 10 min without severe of irreversible health effects. This level was 130 ppm. It was predicted that irritation would occur at this concentration, but the effects on t he respiratory tract would not be "serious" and would be expected to be reversible. The results of this experiment and the subsequent analysis of the data provide an important aid in he planning of responses to an accidental release of HF.

Animals↗
PubMed1998

Epiluminescence microscopy-based classification of pigmented skin lesions using computerized image analysis and an artificial neural network.

Epiluminescence microscopy (ELM) is a non-invasive technique for in vivo examination which can provide additional criteria for the clinical diagnosis of pigmented skin lesions (PSLs). In the present study we attempt to determine whether PSLs can be automatically diagnosed by an integrated computerized system. This system should recognize the PSL, automatically extract features and use these features in training an artificial neural network, which should--if sufficiently trained--be capable of recognizing and classifying a new PSL without human aid. One hundred and twenty images of randomly selected histologically proven PSLs (33 common naevi, 48 dysplastic naevi and 39 malignant melanomas) were used in this study. The images were digitally obtained and the morphological features of the PSLs were extracted electronically without human assistance. The numerical data were then divided into learning and testing cases and linked to an artificial neural network for training and for further classification of lesions that the system had not been trained on. Our results show that the computerized system was able to automatically identify 95% of the PSLs presented. The sensitivity and specificity of the computerized system were 90% and 74% respectively. In contrast, when differentiating between individual types of lesions, the system performed at true positive rates of only 38% for malignant melanoma, 62% for dysplastic naevi and 33% for common naevi. Our data indicate that (1) ELM images of PSLs provide an excellent source for digital image analysis; (2) the vast majority of PSLs can be correctly identified by a relatively simple (and thus not "intelligent") application of digital image analysis; (3) automatic feature extraction based mainly on ABCD rules provides reliable data on the distinction between benign and malignant PSLs; and (4) there is evidence that artificial neural networks can be trained to adequately discriminate between benign and malignant PSLs.

Dysplastic Nevus Syndrome↗
PubMed1998

Adjuvant interferon alfa-2a treatment in resected primary stage II cutaneous melanoma. Austrian Malignant Melanoma Cooperative Group.

PURPOSE: Patients with primary cutaneous melanoma with a Breslow thickness > or = 1.5 mm have only a 30% to 70% probability of survival after surgery, and no adjuvant therapy has so far improved this outcome. Since interferon alfa-2a (IFNalpha2a) exhibits antitumor activity in metastatic melanoma, we investigated whether adjuvant IFNalpha2a diminishes the occurrence of metastases and thus prolongs disease-free survival in melanoma patients after excision of the primary tumor. PATIENTS AND METHODS: In a prospective randomized study, 311 melanoma patients with a Breslow thickness > or = 1.5 mm were assigned to either adjuvant IFNalpha2a treatment (n = 154) or observation (n = 157) after excision of the primary tumor. IFNalpha2a was given daily at a dose of 3 mIU subcutaneously (s.c.) for 3 weeks (induction phase), after which a dose of 3 mIU s.c. three times per week was given over 1 year (maintenance phase). RESULTS: Prolonged disease-free survival was observed in patients treated with IFNalpha2a versus those who underwent surgery alone. This difference was significant (P = .02) for all patients enrolled onto the study (intention-to-treat analysis) at a mean observation time of 41 months. Subgroup analysis showed that Breslow tumor thickness had no influence on treatment results in the groups of patients investigated. CONCLUSION: Adjuvant IFNalpha2a treatment diminishes the occurrence of metastases and thus prolongs disease-free survival in resected primary stage II cutaneous melanoma patients.

Adjuvants, Immunologic↗
PubMed1998

[Diagnosis and therapy of the rupture of both cruciate ligaments, the medial collateral ligament and abscission of both menisci in a ram. A case report].

This report describes the case history of a 1.5-year-old ram admitted to the Clinic for Food Animals and Horses, University of Berne, Switzerland, because of an acute severe lameness of the left rear limb. Clinical and radiographic examination revealed disruption of the stifle joint with rupture of both cruciate ligaments, the medial collateral ligament, and disruption of both menisci from their attachments. The ruptured ligaments were replaced by synthetic ligament prostheses. Long-term examination at 12 months after implantation revealed slight instability of the stifle joint, caused by degeneration of the medial meniscus, and signs of arthrosis deformans. The new formed periarticular connective tissue contributed to the stability of the stifle joint, so that a good functional result was achieved. Necropsy findings at 14 months after implantation confirmed that the synthetic ligament prostheses were intact and the medial meniscus was detached from its insertion and incorporated into the joint capsule. At microscopic examination of the synthetic band prosthesis, ingrowth of collagen and fibrous tissue was evident.

Animals↗
PubMed1997

[Ultrasound biomicroscopy for localization of artificial lens haptics after trans-scleral suture fixation].

Correct positioning of transscleral haptics for sulcus fixation of IOL haptics may be difficult due to lack of visual control by the surgeon. We determined the haptic sites in eyes which underwent secondary IOL implantation with transscleral suturing using ultrasound biomicroscopy (UBM) (Humphrey Instruments, Inc., San Leandro, CA, USA). Eighteen eyes of 17 patients were included in the study. The follow-up time ranged from 1 to 36 months (mean: 7 months). The positions of 36 IOL-haptics were documented by UBM examination. Twelve haptics (33%) were found in the sulcus, whereas 18 haptics (50%) were located posteriorly to the sulcus. Six haptics (17%) were identified anteriorly to the sulcus. There were no complications resulting from dislocation. In one of the eyes, suture infection occurred requiring surgical revision and antibiotic therapy.

Follow-Up Studies↗
PubMed1997

Epiluminescence microscopy of small pigmented skin lesions: short-term formal training improves the diagnostic performance of dermatologists.

BACKGROUND: Epiluminescence microscopy (ELM) makes subsurface structures of the skin accessible for in vivo examination and provides additional criteria for the clinical diagnosis of pigmented skin lesions (PSLs). We demonstrated that ELM increases diagnostic sensitivity in dermatologists formally trained in the use of this technique but decreases diagnostic ability in dermatologists not formally trained in its application. OBJECTIVE: Our purpose was to determine the effects of short formal ELM training on the diagnostic performance of 11 previously untrained dermatologists. METHODS: One hundred image-pairs of randomly selected histologically proven PSLs, photographed with (ELM) and without oil immersion (surface microscopy), were presented by slide projection to the testees. To evaluate the effects on diagnostic performance before and after short-term training, we used the receiver-operator characteristics technique. RESULTS: Without training the use of ELM did not enhance diagnostic accuracy, but rather decreased it in 8 of 11 testees. In contrast, after 9 hours of formal training in ELM the diagnostic performance of the testees was significantly enhanced with an average gain of 8.4%. CONCLUSION: Our data confirm that formal training is required for the useful application of the ELM technique.

Austria↗
PubMed1997

Lymph node sonography versus palpation for detecting recurrent disease in patients with malignant melanoma.

The aim of this study was to examine the efficacy of lymph node palpation versus high resolution lymph node sonography for the detection of lymph node metastases in patients with malignant melanoma. We retrospectively evaluated 2256 pairwise lymph node examinations of the cervical, axillary and inguinal region by palpation and sonography in 264 patients with resected melanomas greater than 0.75 mm of invasion thickness. Lymph node metastases occurred in 50 patients (19%) which were detected in 38 (76%) by both methods in agreement. In 7 cases (14%) palpation failed, in 3 cases (6%) sonography failed and in 2 cases both methods failed to identify metastases. The overall sensitivity of detecting metastatic disease was 82% for palpation and 90% for sonography which was statistically not different. The overall specificity by sonography (99%) was significantly better than for lymph node palpation (88%). Taking into account the results of this analysis, we conclude that patients with a negative result by lymph node palpation do not need further sonography for verification. However, any suspect result by palpation should be additionally evaluated by lymph node sonography in order to rule in or out metastatic disease.

Adolescent↗
PubMed1997

Alexithymia in Holocaust survivors with and without PTSD.

Alexithymia was measured in non-treatment seeking, community-dwelling Holocaust survivors using the Toronto Alexithymia Scale-Twenty Item Version (TAS-20). Scores of survivors with (n = 30) and without (n = 26) posttraumatic stress disorder (PTSD) were compared, and associations among alexithymia, severity of trauma, and severity of PTSD symptoms were determined. Survivors with PTSD had significantly higher scores on the TAS-20 compared to survivors without PTSD. TAS-20 scores were significantly associated with severity of PTSD symptoms, but not with severity of trauma. This study adds to our knowledge of the relationship between alexithymia and trauma by demonstrating that this characteristic is related to the presence of posttraumatic symptoms and not simply exposure to trauma.

Affective Symptoms↗
PubMed1997

Statistical evaluation of epiluminescence microscopy criteria in the differential diagnosis of malignant melanoma and pigmented basal cell carcinoma.

Pigmented basal cell carcinoma (PBCC) is a tumour with distinct clinical features which occasionally may be difficult to differentiate from malignant melanoma (MM). The purpose of this study was to re-examine the epiluminescence microscopy (ELM) criteria for PBCC and to determine their statistical significance in the differential diagnosis of MM. Fifty histologically verified pigmented skin lesions (25 PBCCs and 25 MMs) were investigated using ELM for the presence of ELM criteria; their significance was determined by calculating the odds ratios. We found that individual ELM criteria have different weights of significance in the differential diagnosis of PBCC (leaf-like distribution of diffuse pigmentation, gradual thinning at the periphery and telangiectasia) and MM (pigment network, black and grey pigmentation, radial streaming, pseudopods, brown globules and black dots). Selected patterns of ELM criteria adjusted to the distinct types of pigmented skin lesions are characteristic features for preoperative diagnosis. The prevalence of distinct ELM criteria in PBCC and MM is of critical value in differentiating between the two types of lesions.

Basal Cell Carcinoma↗
PubMed1997

Quantification of vascularity in nodular melanoma and Spitz's nevus.

Spitz's nevi are acquired benign melanocytic skin tumors. Usually they are differentiated from nodular melanoma by clinical and histopathological criteria. Since Spitz's nevi are one of the most common simulators of nodular melanomas their bizarre histopathology may cause diagnostic confusion and make it difficult to differentiate these two melanocytic tumors. One of the histologic features shared by Spitz's nevus and nodular melanoma is prominent vascularity. The ability of malignant melanoma to induce angiogenesis is well established whereas benign melanocytic tumors do not have a prominent overall vascularity. The purpose of this study was to find out whether the degree of vascularity of nodular melanomas differs significantly from that of benign Spitz's nevi. In this study the number of microvessels and the vessel area were determined in 23 Spitz's nevi and 16 nodular melanomas. The number of microvessels and the vessel area were determined on Ulex Europaeus agglutinin I-stained sections by computer-assisted image analysis. Two methods of measurement were used, namely systematic and selective sampling. Measurement of the whole tumor specimen (systematic sampling) revealed a vessel count of 10.83/field (SD +/-5.97) for Spitz's nevi whereas nodular melanomas exhibited a significantly lower (p=0.04) vessel count of 6.44/field (SD +/-3.85). This difference was even more pronounced when the vessel area (Spitz's nevi: 17.85x10-4mm2, SD +/-10.32; nodular melanomas: 7.88x10-4mm2, SD +/-5.23) was investigated (p < 0.001). The difference in vessel area and vessel count was insignificant for areas exhibiting the greatest vascularity (selective sampling). Measurement of vessel count and vessel area lead us to conclude that Spitz's nevi have a significantly higher vascularity than do nodular melanomas. Our results thus indicate that angiogenesis in these pigmented lesions is not correlated with malignancy.

Humans↗
PubMed1997

[Retropharyngeal abscess in cattle. A case report].

This case report describes history, clinical, laboratory, radiographic, and endoscopic findings, therapy, and outcome of a 5-year-old cow, suffering from retropharyngeal abscessation. Clinical findings at admission included elevated body temperature, head and neck held in extended position, excessive salivation, swelling of the retropharyngeal area, and slight inspiratory noise. Radiographic and endoscopic examination confirmed the tentative diagnosis of retropharyngeal abscessation. Treatment consisted of parenteral application of procaine-penicillin for 10 days and local application of linseed rubefacients for 2 weeks. At that time, abscessation had developed. The abscess was subsequently surgically, approached by a modified Whitehouse approach. During this procedure, the abscess drained into the oropharynx, allowing interruption of surgery. Five months later, clinical, radiographic, and endoscopic follow-up examination revealed complete healing of the retropharyngeal abscess.

Animals↗
PubMed1997

Myoelectric activity of the cecum and proximal loop of the ascending colon in cows after spontaneous cecal dilatation/dislocation.

OBJECTIVE: To analyze myoelectric activity of the cecum and proximal loop of the ascending colon (PLAC) in cows after spontaneous cecal dilatation/dislocation (CDD) and compare it with that in healthy cows after surgical evacuation of the cecum. ANIMALS: 12 cows with spontaneous CDD and 6 healthy cows (group C). Cows with spontaneous CDD were retrospectively assigned to 2 groups: delayed recovery from surgery or recurrence (group A; n = 3), and normal recovery (group B; n = 9). PROCEDURE: After surgical evacuation of the cecum, 8 pairs of bipolar, retrievable electrodes were implanted in the ileum, cecum, and PLAC. Cows were evaluated daily from postoperative day 1 to 7, using routine clinical methods and computer-based analysis of myoelectric activity of the cecum, and PLAC. Parameters of myoelectric activity included rate of spike bursts, duration of individual spike bursts, duration of overall spike burst activity per electrode, rate of propagated spike burst sequences, and ratio of orally propagated spike burst sequences. RESULTS: Rate of spike bursts, duration of cecocolic spike burst activity, and ratio of orally to aborally propagated spike burst sequences did not vary among groups during the 7-day recording period. However, cows with delayed recovery had a typical, uniform pattern of myoelectric activity of the cecum and PLAC at days 1 and 2 after surgery that consisted of repeated, propagated spike burst sequences, made up of spike bursts of significantly (P < 0.05) increased duration at postsurgical day 1 and substantially prolonged duration at postsurgical day 2, interrupted by periods of little or no activity. CONCLUSION: Delayed recovery and recurrence of CDD in cows after spontaneous CDD is not caused by hypomotility of the cecum and PLAC. CLINICAL RELEVANCE: Postoperative treatment, intended to reduce recurrence of CDD or delayed recovery after surgical evacuation of the cecum, should address propagation of digesta in the spiral colon.

Animals↗
PubMed1997

[Surgical treatment of carpal hygroma in cattle: 17 cases (1990-1994)].

This retrospective study describes the case reports of 17 cattle suffering from precarpal hygroma, admitted to the clinic for food animals and horses, University of Berne, between 1990 and 1994. The following criteria were evaluated: sex, age, and bodyweight, case history, clinical findings at admission, surgical technique, aftercare, and short- and long-term results. The hygroma was congenital in 3 cases and acquired at the age of 2 to 84 months in 14 cases. Characteristic clinical findings at admission were a non painful, fluctuating, well delineated swelling of the precarpal area with a maximal diameter of 6 to 20 cm, which did not provoke any lameness. Treatment consisted of surgical excision of the bursa. Surgery was performed under general anesthesia with the animal in lateral recumbency and the affected limb positioned uppermost. After placing a tourniquet proximal to the carpal joint, routine preparation and draping of the surgical field, the bursa was resected completely, a penrose drain introduced, and primary wound closure attempted. Aftercare consisted of parenteral antimicrobial treatment and immobilisation of the affected limb with a full-limb splint bandage to prevent wound dehiscence and seroma formation. Primary wound healing was achieved in all cases. At the time of long-term follow-up evaluation, 4 to 48 months after surgery, telephone conversation with the owners revealed uncomplicated healing in 16 cases. In one case, recurrence of the hygroma had occurred a few weeks after surgical excision had been performed.

Animals↗
PubMed1996

[Analysis of various continuing medical education courses].

Two types of postgraduate medical education were analyzed by questionnaires: 'afternoons for practitioners' taking place at the university clinics in Zurich and 'seminars in internal medicine' held for 2 1/2 days in the seminar facilities of a pharmaceutical firm in Freiburg (Germany). For both cases, the demand for and the interest in the event was confirmed. Overall, those presentations were favoured which offered more time for an interaction with the speaker. Since the interest of the participants focussed on practical aspects, those presentations received better marks that addressed medical practice directly. Furthermore, teaching methods encouraging active collaboration by the participants were favoured. Speakers at the 'seminars in internal medicine' were informed about acceptance of their performance, thus leading to an improvement of subsequent seminars. Our findings encourage to analyze in depth continuing postgraduate education events in the future. The feedback of the assessment by participants to the speakers leads to significant improvements.

Consumer Behavior↗