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T Schreiner

Publications and source records attributed to T Schreiner.

At least 19 recordsLinked to original sources
PubMed2006

Serum GH and IGF-I are significant determinants of bone turnover but not bone mineral density in active acromegaly: a prospective study of more than 70 consecutive patients.

OBJECTIVE: Acromegaly is characterized by a persistent hypersecretion of GH and provides information on long-term effects of GH on bone metabolism. The aim of this study was to examine the effect of gonadal status and disease activity on bone metabolism in active acromegaly. METHODS: Seventy-three consecutive patients with active acromegaly: 40 women and 33 men (50 +/- 13 (mean +/- s.d.) and 49 +/- 10 years respectively) were evaluated and compared with age-, sex-, and body mass index (BMI)-matched controls by X-ray absorptiometry and biochemical analysis (markers of disease activity and bone turnover). RESULTS: We found that bone turnover, as evaluated by biochemical bone markers, is coupled and markedly increased in relation to disease activity in active acromegaly. Acromegalic women, but not men, were characterized by an increased bone area and slightly decreased bone mineral content resulting in significantly decreased bone mineral density (BMD) in the ultradistal radius, proximal radius, and total body. No differences in bone turnover or BMD were found between eu-and hypogonadal subjects. Multivariate analysis identified age, BMI, and gender as independent predictors of total BMD in acromegaly. CONCLUSION: Our study demonstrates a decreased total body BMD in women, not men, with active acromegaly, regardless of gonadal status or disease activity. Bone turnover is markedly increased in relation to disease activity, possibly counteracting the anabolic effects of excess GH/IGF-I in these subjects. We suggest more focus on biomechanical analyses when investigating endocrine disorders affecting bone size and distribution between compartments.

Acromegaly↗
PubMed2005

Small-scale extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma: a report of 3 cases.

Extracorporeal photopheresis is an accepted method for the treatment of cutaneous T-cell lymphoma and much progress has recently been achieved in therapy and understanding of its mechanism. In general large numbers of white blood cells are collected by a cell separator and irradiated in the presence of 8-MOP. In contrast to this practice, data from an animal model showed that as few as 0.2% of the body's blood volume irradiated are sufficient to achieve an immune response after photopheresis. Based on these data we developed a small-scale photopheresis procedure and applied the method in 3 end-stage T-cell lymphoma patients who were not eligible for apheresis. The mononuclear cells from 50 ml of blood were separated by density gradient centrifugation, irradiated with UV-light in the presence of 8-Methoxy-Psoralen (MOP) with 2J/cm(2) and reinjected. 2-3 treatments per week were conducted. The three patients-2 male and 1 female, age 63-86, Sezary syndrome (1x) and mycosis fungoides in tumour stage (2x)-showed no side effects on cell injection. The two patients with mycosis fungoides showed a prompt regression and softening of the tumours. The patient with Sezary syndrome developed numerous necrotic spots on the skin after 6 weeks of therapy that turned normal within a few days. Patient 1 died of pneumonia 4 weeks after the start of therapy and patient 3 died of heart failure 8 weeks after start of therapy, both during regression of the tumours. Patient 2 was treated over a period of 11 months, with an initial regression in the first weeks followed by a slow progression of the tumours after she rejected any form of further treatment. The small-scale extracorporeal photopheresis therapy presented is effective in cutaneous T-cell lymphoma. But questions regarding the optimal number of cells irradiated per treatment, the conditions of cell incubation after irradiation and the number of treatment cycles are still open. Therefore further studies are required to establish a method that is effective and circumvents the use of apheresis technology.

Aged↗
PubMed2003

Growth hormone substitution increases gene expression of members of the IGF family in cortical bone from women with adult onset growth hormone deficiency--relationship with bone turn-over.

OBJECTIVE: To investigate the effects of growth hormone (GH) replacement therapy on bone matrix gene expression of insulin-like growth factors (IGFs) and markers of bone metabolism in women with adult-onset GH deficiency (GHD). DESIGN AND METHODS: Nineteen women, mean age 45 (range 24-56) years, were included in a double-blind, placebo-controlled parallel group study for 12 months. Biochemical markers were measured at baseline, 6 and 12 months. Bone biopsies were obtained and BMD was measured at baseline and after 12 months. RESULTS: Maximum responses were observed after 6 and 12 months, for bone resorptive and bone formative markers respectively. GH therapy enhanced gene expression in cortical bone of IGFs, GH-and calcitonin-receptor (CR) and osteoprotegerin (OPG), however with the most pronounced effects on CR and IGF-I. Changes in IGF-I gene expression during longitudinal follow-up were significantly correlated with changes in both circulating IGF-I (r = 0.82, p < 0.05), changes in markers of enhanced osteoclastic activity, measured both locally in bone (CR, r = 0.87, p < 0.01) and in serum (CTX-I, r = 0.86, p < 0.05), as well as serum bone ALP (r = 0.96, p < 0.01). CONCLUSIONS: This study indicates that both liver- and bone-derived IGF-I may be significant in mediating the effects of GH on bone metabolism in humans.

Adult↗
PubMed2001

Standardized ultrasound as a new method to induce platelet aggregation: evaluation, influence of lipoproteins and of glycoprotein IIb/IIIa antagonist tirofiban.

Most of the published studies concerning platelet aggregation were performed with chemical stimulation procedures, however, mechanical stimulation might be a better simulation of physiological activation of platelets. In order to evaluate the influence of ultrasound on platelet aggregation in vitro, we developed an ultrasound device in a standardized set-up, and we evaluated the influence of lipoproteins and the glycoprotein IIb/IIIa inhibitor tirofiban on ultrasound induced platelet aggregation. A cylindrical shaped plastic test tube with 1 ml of platelet-rich plasma was placed in an ultrasound bath (35 kHz) for 5 s. The ultrasound energy transfer into the sample (Delta W=3.77 J) was calculated using the average temperature increase (averaged by 0.935 degrees C) of the sample. Platelet aggregation was quantified immediately after stimulation with ultrasound or adenosine diphosphate (ADP 2.1 and 4.2 microM) by the Myrenne Aggregometer PA2 at low (40 s(-1)) and afterwards at high (2500 s(-1)) shear. To evaluate the influence of lipoproteins, seven healthy male volunteers were investigated before and after a fat load (50 g fat per m(2) body surface), and 11 patients suffering from hypercholesterolemia and atherosclerotic disease before and after a single low-density lipoprotein (LDL) apheresis. Platelet aggregation after ultrasound stimulation was well correlated with platelet aggregation after ADP (r between 0.50 and 0.95). However, when exposed to high shear, the low shear-induced platelet aggregates were more stable after ultrasound stimulation compared with ADP stimulation either with or without tirofiban. After the fat load triglyceride concentration increased from 0.86+/-0.39 to 2.10+/-1.10 mmol l(-1) (P<0.05) resulting in a reduced formation of platelet aggregates after weak (ADP 2.1 microM) but not after strong (ADP 4.2 microM or ultrasound) stimuli. After a single LDL apheresis LDL cholesterol dropped from 3.99+/-0.90 to 1.06+/-0.55 mmol l(-1) (P<0.005). No changes in platelet aggregation were observed with the exception of a lower aggregation when exposed to high shear after stimulation with 2.1 microM ADP. In conclusion, we found the ultrasound stimulation of platelet-rich plasma easy to perform. The platelet aggregation after ultrasound stimulation correlated well with stimulation after ADP. While a reduction in LDL cholesterol concentration had only slight effects on platelet aggregation, an increase in triglyceride concentration resulted in a reduced formation of platelet aggregates after weak stimulation.

Blood Platelets↗
PubMed2001

First experience with a ready-for-use rheohemapheresis system.

Rheohemapheresis is increasingly being used for the improvement of microcirculation in numerous diseases. The method is based on the constant-flow separation of plasma by a cell separator and the secondary filtration of plasma through a hollow-fiber membrane. A new CE-marked system has recently been launched for an improved continuous flow blood separator (dideco Excel Pro) that contains a connection kit between the cell separator and a secondary filter and software which includes differential filtration as a standard protocol. The new system was used in our center using ethylenevinylalcohol secondary filters (Evaflux LA4 or LA5). 99 procedures were completed in 47 patients. A median of 2.7 (1.6-4.2) 1 of plasma were processed via the secondary filter in 109 (41-218) min. The values in peripheral blood before and after the treatment were total protein 6.7 (5.8-8.9)/ 5.3 (4.4-6.7) g/dl, fibrinogen 215 (118-480)/110 (37-275) mg/dl and cholesterol 200 (134-254)/92 (69 149) mg/dl. A median platelet loss of 30% in the peripheral blood of the patients was observed partly by platelet content of the separated plasma of 30 g/l after 500 ml of treatment and 10 g/l after 2,500 ml. Major side effects in the patients were not observed. The new differential filtration system already fulfills the demands of a ready-to-use CE-marked rheohemapheresis system but improvements in the details of the treatment protocol are still required and under way.

Adult↗
PubMed2001

The role of rheology in hemapheresis.

Rheological therapy attempts to favorably influence the blood flow mechanics for the treatment of diseases, mainly of the microcirculation but also of the macrocirculation. Hemapheresis, originally used only for the elimination of an excess of cellular or plasmatic components, was shown to also influence the hemorheology favorably. As extracorporeal therapy affects the rheology much more than conventional hemorheotherapy, not only cellular or plasmatic hyperviscosity syndromes but also many more diseases associated with organ perfusion problems due to diseases of the micro- and macrocirculation, especially in the elderly, were and are increasingly considered to be indicated. Technical progress led away from plasma exchange as an unspecific and unselective procedure to plasma differential separation using precipitation. adsorption, and filtration. With our recent development, we demonstrated that rheohemapheresis is the most advanced technical procedure. The mechanism of action can well be related to a synergetic consideration of rheology. However. one has to keep in mind that the elimination of blood components such as lipids, immunoglobulins, and endothelial factors may well contribute to the explanation and understanding of the positive clinical effects observed. These speculative aspects need further investigation.

Adult↗
PubMed2000

Prevalence of thyroid disease, thyroid dysfunction and thyroid peroxidase antibodies in a large, unselected population. The Health Study of Nord-Trondelag (HUNT).

OBJECTIVE: To examine the prevalence of thyroid disease and dysfunction including thyroid autoimmunity in Norway. MATERIALS AND METHODS: All inhabitants 20 years and older (94009) in Nord-Trondelag were invited to participate in a health survey with a questionnaire and blood samples. RESULTS: The prevalence of former diagnosed hyperthyroidism was 2.5% in females and 0.6% in males, hypothyroidism 4.8% and 0.9%, and goitre 2.9% and 0.4% respectively. In both sexes the prevalence increased with age. In individuals without a history of thyroid disease the median, 2.5 and 97.5 percentiles for TSH (mU/l) were 1.80 and 0.49-5.70 for females and 1. 50 and 0.56-4.60 for males. The TSH values increased with age. When excluding individuals with positive thyroid peroxidase antibodies (TPOAb) (>200U/ml), the 97.5 percentiles dropped to 3.60 mU/l and 3. 40 mU/l respectively. The prevalence of pathological TSH values in females and males were TSH >/=10mU/l 0.90% and 0.37%; TSH 4.1-9. 9mU/l 5.1% and 3.7%; and TSH</=0.05mU/l 0.45% and 0.20% respectively. The prevalence of positive TPOAb (>200U/ml) was 13.9% in females and 2.8% in males. In females the lowest percentage (7.9%) of positive TPOAb was seen with TSH 0.2-1.9mU/l and increased both with lower and higher levels of TSH. The percentage of males with positive TPOAb was lower than in females in all TSH groups except for those with TSH>10mU/l (85% TPOAb positive). CONCLUSIONS: In spite of a high prevalence of recognised thyroid disease in the population a considerable number of inhabitants have undiagnosed thyroid dysfunction and also positive TPOAb.

Adult↗
PubMed1999

Definition of a critical T cell threshold for prevention of GVHD after HLA non-identical PBPC transplantation in children.

The aim of this study was to reduce the rate of graft failure after HLA non-identical stem cell transplantation by using G-CSF mobilized CD34+ peripheral blood progenitor cells (PBPC), either in combination with bone marrow or as single grafts. To prevent GVHD, PBPC were highly purified, resulting in a 5 to 6 log T cell depletion. In additon to T cell depletion no further GVHD prophylaxis was used. We transplanted 23 pediatric patients with life-threatening malignant or non-malignant hematological disorders, who had no available matched donor. Engraftment was obtained in 18 of 21 evaluable patients. Five patients developed acute GVHD of grade II and III, which became chronic in four cases and was fatal in four. The use of highly purified PBPC allowed the exact quantification of residual T cells in the grafts and a strict correlation between the residual T cell load and the development of GVHD was observed: patients with GVHD had received numbers of T cells between 8 and 20 x 104/kg, whereas patients without GVHD were grafted with T cell numbers ranging from 0.7 to 6.0 x 104/kg. We therefore clearly demonstrate that a residual T cell content of <5 x 104/kg is safe for prevention of GVHD after HLA non-identical PBPC transplantation in children.

Adolescent↗
PubMed1999

Comparison of T-cell-depleted BMT and PBPCT with respect to chimerism, graft rejection, and leukemic relapse.

Chimerism analysis by DNA-based methods is a valuable diagnostic tool for monitoring engraftment and leukemic relapse after allogeneic BMT or PBPC transplantation (PBPCT). We investigated the chimerism after T-cell-depleted BMT (n = 32) in comparison with T-cell-depleted PBPCT (n = 39). BM grafts were T-cell depleted using the Campath-IgM antibody plus complement. For T-cell depletion of the PBPC grafts, a selection of CD34+ cells with or without a subsequent CD2/3 depletion was performed. In all patients, the T-cell dose of the transplant was < 10(6)/kg body weight. Between day 13 and day 120 after transplantation, chimerism analysis was done by RFLP or amplified fragment length polymorphism (PCR-AFLP), with a detection limit of 1%-5% recipient cells. In the BMT group, 8 of 32 (25%) patients showed a mixed chimerism, but only one graft rejection and no leukemic relapse occurred after a median follow-up of 41 (3-84) months. All patients with PBPCT revealed a complete chimerism of their granulocytes, and 38 of 39 patients showed complete chimerism of their lymphocytes. Follow-up time in these patients is 7 (2-21) months, with no graft rejection and two leukemic relapses. G-CSF-mobilized PBPC are superior to BM cells for full engraftment even after T-cell-depleted transplantation. The more relevant factor for developing complete chimerism seems to be the quantity and possibly the quality of the stem cells rather than the residual T-cell load of the graft. However, a mixed chimerism of the lymphocytes early after transplantation does not predict a higher rate of graft rejection or leukemic relapse.

Adult↗
PubMed1999

Lipid peroxidation in human spermatozoa and maintenance of progressive sperm motility.

Washed and deep frozen spermatozoa of 46 patients from an infertility clinic were separated into 3 different groups depending on their progressive motility (expressed as the sperm motile efficiency index according to Ishii et al., 1977), determined 0 and 3 h after liquefaction, and were examined for their lipid peroxidation (LPO) potential by means of the thiobarbituric acid assay. Spontaneous and iron-catalysed generation (after 15, 30 and 60 min incubation) of thiobarbituric acid-reactive substances (TBARS) was measured spectrophotometrically. Spontaneous LPO revealed the highest generation of TBARS in the group of spermatozoa with initially normal progressive motility and decreased maintenance of progressive motility after 3 h of aerobic incubation. Iron-catalysed LPO generally revealed the highest amounts of TBARS after 60 min, especially in the aforementioned group with decreased motility maintenance. The differences between this group and the two other groups were highly significant. Consequently, spermatozoa with initially normal progressive motility but decreased maintenance of motility, generated higher amounts of stable LPO products than others, which suggests that loss of motility under aerobic incubation seems to be the consequence of enhanced LPO processes.

Catalysis↗
PubMed1998

Anaphylactic reaction to bovine serum albumin after embryo transfer.

OBJECTIVE: To increase the awareness of bovine serum albumin (BSA) sensitivity as a potentially lethal complication during ET. DESIGN: Case report. SETTING: Routine ET in university hospital. PATIENT(S): A 26-year-old woman who was undergoing her first ET. INTERVENTION(S): ET with BSA containing standard fluid medium. MAIN OUTCOME MEASURE(S): Specific immunoglobulin (Ig) E antibodies and skin tests. RESULT(S): The patient demonstrated increased levels of specific IgE antibodies to BSA and a clearly positive scratch test for BSA. CONCLUSION(S): Anaphylactic reactions to BSA can occur during ET. The risk can be reduced substantially if a detailed medical history is obtained.

Adult↗
PubMed1998

Septate uterus.

Explore the source record for details and available documents.

Female↗
PubMed1998

Mobilization and collection of allogeneic peripheral blood progenitor cells for transplantation.

A median dose of 11 (6-17) microg G-CSF per kg and day was given to 96 (49 female, 47 male) healthy family donors in order to mobilize and to collect peripheral blood progenitor cells (PBPC) for allogeneic transplantation. Donor age was 36 (17-76) years. The leukocytes of the donors increased to 46 (12-115) x 10(9)/l on days 4-6 of G-CSF treatment with a median of 71 (2-657) CD34+ cells per microl, respectively. Female and older donors seem to have a lower response to G-CSF. About 32% of the donors suffered from side-effects of G-CSF requiring analgetics. A total of 197 stem cell aphereses were performed using the COBE Spectra cell separator. Median apheresis time was 225 (118-300) min processing 11.8 (5.7-20) l blood, collecting 5.3 (1.7-14.9) x 10(10) nucleated cells and containing 0.7 (0.1-3.7)% CD34+ cells. Severe citrate toxicity occurred in 5% of the donors. Retransfusion of autologous platelets post apheresis was necessary in 16% of the donors because of a platelet count <80 x 10(9)/l. An insufficient number of stem cells was collected in four female donors due to a very poor response to G-CSF. In conclusion, the collection of allogeneic G-CSF-mobilized PBPC is safe and effective. One or two aphereses were sufficient in 91% of the donors to achieve >4 x 10(6) CD34+ cells per kg. In 4% of the donors an additional bone marrow harvest or the use of an alternative donor was necessary because of a poor mobilization.

Adolescent↗
PubMed1997

Recurrence of hydrosalpinges after transvaginal aspiration of tubal fluid in an IVF cycle with development of a serometra.

The presence of hydrosalpinges has been shown to be deleterious in infertility treatment. Pregnancy rates after in-vitro fertilization (IVF) with embryo transfer decline considerably. This study concerns a patient who developed bilateral hydrosalpinges during controlled ovarian stimulation in preparation for IVF treatment. Transvaginal aspiration of the tubal fluid was unsuccessful as the tubes refilled within 2 days. Additionally, on the day of embryo transfer a serometra developed which could not be seen on the day of oocyte retrieval. The uterine cavity was evacuated via an embryo transfer catheter and three embryos were transferred. The serometra reappeared 3 days after embryo transfer. A pregnancy could not be achieved. The accumulation of fluid in the uterine cavity during an IVF/embryo transfer cycle is a rare complication of hydrosalpinges. However, the retrograde flow of tubal fluid may disturb intrauterine embryo development. This study suggests that the aspiration of hydrosalpinges and intrauterine fluid accumulation during an IVF cycle is not beneficial, as the underlying pathology is not cured. Cancellation of the treatment cycle or cryopreservation of oocytes in the pronucleate stage and transfer of the cryopreserved oocytes after surgical correction of the tubes may be better options.

Exudates and Transudates↗