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P M Schmidt

Publications and source records attributed to P M Schmidt.

At least 19 recordsLinked to original sources
PubMed2000

CD34/QBEND10 immunostaining in bone marrow biopsies: an additional parameter for the diagnosis and classification of myelodysplastic syndromes.

CD34/QBEND10 immunostaining has been assessed in 150 bone marrow biopsies (BMB) including 91 myelodysplastic syndromes (MDS), 16 MDS-related AML, 25 reactive BMB, and 18 cases where RA could neither be established nor ruled out. All cases were reviewed and classified according to the clinical and morphological FAB criteria. The percentage of CD34-positive (CD34 +) hematopoietic cells and the number of clusters of CD34+ cells in 10 HPF were determined. In most cases the CD34+ cell count was similar to the blast percentage determined morphologically. In RA, however, not only typical blasts but also less immature hemopoietic cells lying morphologically between blasts and promyelocytes were stained with CD34. The CD34+ cell count and cluster values were significantly higher in RA than in BMB with reactive changes (p<0.0001 for both), in RAEB than in RA (p=0.0006 and p=0.0189, respectively), in RAEBt than in RAEB (p=0.0001 and p=0.0038), and in MDS-AML than in RAEBt (p<0.0001 and p=0.0007). Presence of CD34+ cell clusters in RA correlated with increased risk of progression of the disease. We conclude that CD34 immunostaining in BMB is a useful tool for distinguishing RA from other anemias, assessing blast percentage in MDS cases, classifying them according to FAB, and following their evolution.

Adolescent↗
PubMed2000

Factors affecting the efficiency of embryo cryopreservation and rederivation of rat and mouse models.

The efficiency of embryo banking for rat and mouse models of human disease and normal biological processes depends on the ease of obtaining embryos. Authors report on the effect of genotype on embryo production and rederivation. In an effort to establish banks of cryopreserved embryos, they provide two databases for comparing banking efficiency: one that contains the embryo collection results from approximately 11,000 rat embryo donors (111 models) and another that contains the embryo collection results from 4,023 mouse embryo donors (57 induced mutant models). The genotype of donor females affected the efficiency of embryo collection in two ways. First, the proportion of females yielding embryos varied markedly among genotypes (rats: 16-100 %, mean =71 %; mice: 24-95 %, mean =65 %). Second, the mean number of embryos recovered from females yielding embryos varied considerably (rats: 4-10.6, mean =7.8; mice 5.3-32.2, mean =13.7). Genotype also affected the efficiency of rederivation of banked rat and mouse embryos models by embryo transfer. For rats, thawed embryos (n =684) from 33 genotypes were transferred into 66 recipient females (pregnancy rate, 78 %). The average rate of developing live newborns for individual rat genotypes was 30 % with a range of 10 to 58 %. For mice, thawed embryos (n =2,064) from 59 genotypes were transferred into 119 pseudopregnant females (pregnancy rate: 76 %). The average rate of development of individual mouse genotypes was 33 % with a range of 11 to 53 %. This analysis demonstrates that genotype is an important consideration when planning embryo banking programs.

Animals↗
PubMed1998

Superovulation of rabbits with FSH alters in vivo development of vitrified morulae.

Morulae were flushed from the oviducts and uteri of New Zealand White (NZW) rabbits superovulated with either 6 (3 d) or 8 (4 d) injections of FSH and from non-superovulated controls. The percentages of embryos recovered from 4 d (100%, n = 8) donors was significantly higher (P < 0.01) than that of 3 d (76%, n = 16) and control (87%, n = 22) donors. Overall, fertilization rates were significantly lower for the 3 d embryos (P < 0.01). Most (86 to 90%) morulae were morphologically suitable for vitrification in an ethylene glycol-based solution. Following storage in liquid nitrogen, morulae were rapidly thawed and transferred to the uteri of pseudopregnant recipients. The total number of kits born for the 3 d, 4 d, and control groups was 40, 61 and 48, respectively. The percentage of live kits from morulae transferred was significantly lower for the 3 d (20%, n = 201) than either the 4 d (36%, n = 169; P < 0.01) or the control (31%, n = 157; P < 0.05) group. The mean number of kits born/recipient for the 3 d (2.4 +/- 2.9), 4 d (4.7 +/- 3.5), and control (3.0 +/- 2.2) protocols did not differ (P > 0.05). The estimated overall efficiency of producing kits based on normal morulae collected for control and 4 d groups, however, was nearly two-fold that for females given 6 FSH treatments. We conclude that the 4 d FSH superovulation regimen enhances the efficiency of rabbit reproductive biotechnology after embryo cryopreservation. These findings have important implications for rabbit colony management using embryo cryopreservation.

Animals↗
PubMed1997

Systemic mastocytosis following a malignant ovarian germ cell tumour.

Cases of mediastinal germ cell tumours associated with haematological disorders (two cases of systemic mastocytosis included) have been reported previously. This combination is more frequent than would be expected by chance alone. We report the case of a 30-year-old woman, who presented with a systemic mastocytosis following a malignant ovarian germ cell tumour which was treated by chemo- and radiotherapy. The patient predominantly complained of skeletal pains, which led to an erroneous radiological diagnosis of fibrous dysplasia for years. An aggressive variant of systemic mastocytosis was diagnosed on bone marrow examination. Systemic mastocytosis was confirmed by splenectomy, liver biopsy and finally autopsy. The present case is unique because of the ovarian location of the germ cell tumour. We suggest our observation could be related to the broad group of haematological malignancies associated with germ cell tumours.

Adolescent↗
PubMed1996

Tetrasomy 8 in a patient with acute nonlymphocytic leukemia: a metaphase and interphase study with fluorescence in situ hybridization.

Tetrasomy 8 constitutes a relatively rare recurring chromosome defect in myeloid disorders. The patient reported here, a 71-year-old man, presented with tetrasomy 8 as the sole chromosome abnormality associated with an acute nonlymphocytic leukemia of the M2 type. He failed to respond to chemotherapy and died one year after diagnosis. Following conventional cytogenetics and fluorescence in situ hybridization (FISH) with a centromeric probe specific for chromosome 8, tetrasomy 8 was detected in 61% of the metaphases analyzed and trisomy 8 in 39%. FISH analysis of interphase nuclei confirmed the existence of tetrasomic (35%) and trisomic cells (56%) and revealed a number of cells with two chromosomes 8 (8%). This normal population may represent lymphocytes or myeloid cells that escaped conventional analysis due to their inability to divide or to the small number of metaphases available. The relatively higher proportion of tetrasomic cells in metaphase compared with interphase may be attributed to a proliferative advantage of tetrasomic cells in vitro or to the longer duration of their cell cycle. The simultaneous presence of trisomic and tetrasomic cells confirms the hypothesis of a clonal relationship between trisomy 8 and tetrasomy 8. Our case brings further evidence to the specificity of tetrasomy 8 to myeloid disorders and to the association of this chromosome abnormality with a relatively poor prognosis. However, new patients must be studied to further delineate this cytogenetic entity.

Aged↗
PubMed1996

Combined effects of interleukin-3 and interleukin-11 on hematopoiesis in irradiated mice.

The survival rate and recovery of peripheral blood cells and platelets were studied in Balb/c mice subjected to different single doses of whole-body irradiation and treated with a combination of interleukin-3 (IL-3) and interleukin-11 (IL-11). In a first group of 20 mice, 7.5 Gy irradiation, immediately followed by 2 and 5 days therapy of IL-3 and IL-11, respectively, increased the survival rate to 82% compared to 20% in untreated controls. In a second group of mice irradiated with 7 Gy, we observed significantly higher platelet, white blood cell (WBC), and red blood cell (RBC) counts after treatment with both cytokines, as compared to IL-3 or IL-11 alone or untreated controls. In addition, the survival rate of the mice with the combined therapy was also increased to 84%, compared to 48% in untreated controls. Irradiation (8.5 Gy) gave 100% mortality for the control mice, and therapy with combined IL-3 plus IL-11 had only a marginal effect. Interestingly, syngeneic bone marrow transplantation (BMT) alone, performed 16 hours after irradiation, increased the survival rate to 70%, while BMT combined with administration of IL-3 plus IL-11 increased it to 97%. Furthermore, BMT combined with cytokine administration could partially prevent the severe WBC and RBC depletion observed in mice treated with BMT alone and promoted a more rapid recovery of platelets and RBC. These data show that the combination of IL-3 and IL-11 has a radioprotective effect and can enhance recovery of platelets, WBC, and RBC in irradiated mice. Combined IL-3 plus IL-11 therapy may be clinically useful in myelodepression, especially in platelet depletion related to radiation therapy or chemotherapy, or after bone marrow transplantation.

Animals↗
PubMed1995

Prediction of 18-month survival in patients with primary myelodysplastic syndrome. A regression model and scoring system based on the combination of chromosome findings and the Bournemouth score.

The predictive potential of six selected factors was assessed in 72 patients with primary myelodysplastic syndrome using univariate and multivariate logistic regression analysis of survival at 18 months. Factors were age (above median of 69 years), dysplastic features in the three myeloid bone marrow cell lineages, presence of chromosome defects, all metaphases abnormal, double or complex chromosome defects (C23), and a Bournemouth score of 2, 3, or 4 (B234). In the multivariate approach, B234 and C23 proved to be significantly associated with a reduction in the survival probability. The similarity of the regression coefficients associated with these two factors means that they have about the same weight. Consequently, the model was simplified by counting the number of factors (0, 1, or 2) present in each patient, thus generating a scoring system called the Lausanne-Bournemouth score (LB score). The LB score combines the well-recognized and easy-to-use Bournemouth score (B score) with the chromosome defect complexity, C23 constituting an additional indicator of patient outcome. The predicted risk of death within 18 months calculated from the model is as follows: 7.1% (confidence interval: 1.7-24.8) for patients with an LB score of 0, 60.1% (44.7-73.8) for an LB score of 1, and 96.8% (84.5-99.4) for an LB score of 2. The scoring system presented here has several interesting features. The LB score may improve the predictive value of the B score, as it is able to recognize two prognostic groups in the intermediate risk category of patients with B scores of 2 or 3. It has also the ability to identify two distinct prognostic subclasses among RAEB and possibly CMML patients. In addition to its above-described usefulness in the prognostic evaluation, the LB score may bring new insights into the understanding of evolution patterns in MDS. We used the combination of the B score and chromosome complexity to define four classes which may be considered four possible states of myelodysplasia and which describe two distinct evolutional pathways.

Chromosomes, Human↗
PubMed1994

Hematologic, clinical, and cytogenetic analysis in 109 patients with primary myelodysplastic syndrome. Prognostic significance of morphology and chromosome findings.

One hundred and nine patients with primary myelodysplastic syndrome (MDS) were classified according to the French-American-British (FAB) criteria: 27 refractory anemia (RA, 25%), 26 RA with ringed sideroblasts (RARS, 24%), 16 RA with excess of blasts (RAEB, 15%), 10 RAEB in transformation (RAEB-t, 9%), 25 chronic myelomonocytic leukemia (CMMoL, 23%), and five unclassifiable MDS (4%). Forty-three were women and 66 were men (sex ratio 2:3). Age ranged from 30-92 years (mean 69 years) with nine patients aged less than 50 years (8%). A cytogenetic result was obtained in all cases. At initial study, a chromosome defect was observed in 56% of patients. Rates of abnormality depended on FAB subtype: 52% in RA, 100% in RA 5q-, 50% in RARS, 56% in RAEB, 70% in RAEB-t and 44% in CMMoL. The most frequent single defects were del(5q), -7/del(7q), del(20q), Y loss, and +8. Except for the 5q- syndrome entity, specific chromosome defects were not associated with particular FAB subtypes. Bone marrow (BM) insufficiency (22%) and leukemic transformation (21%) were the most important causes of death. The rate of leukemic transformation increased with the number of dysplastic BM cell lineages and was also associated with karyotype complexity and the proportion of abnormal/normal metaphases. The longest median survivals were observed in RARS (142 months) and RA/RA5q- (91 months) types. Median survivals decreased with increasing Bournemouth score values. Patients with three abnormal cell lineages had a median survival shorter than those with one or two abnormal lineages. Similarly, patients with complex defects had shorter survival than those with single or double defects or a normal karyotype. There was no statistically significant difference between survival of NN (normal), AN (abnormal/normal), and AA patients or between survival of patients with del(5q), -7/del(7q), +8 or del(20q).

Adult↗
PubMed1992

[Acquired factor V inhibitor treated with intravenous immunoglobulins].

We report the appearance of a factor V inhibitor in an 82-year-old female patient following abdominal surgery. This anomaly was totally corrected following 9-day treatment with i.v. immunoglobulins (0.4 g/kg/day), which allowed a needed further surgical intervention to be performed without hemorrhagic diathesis. The activity of this inhibitor was partly reversed by the in vitro addition of immunoglobulins, suggesting a concentration-effect relationship. This finding supports the hypothesis that anti-idiotypic antibodies could play a role in the therapeutic effect of immunoglobulins in such situations.

Aged↗
PubMed1992

Lack of antibody specificity by mouse trophectoderm during immunosurgery.

Immunosurgery of blastocyst-stage embryos is an effective procedure for isolating the inner cell mass. The ability of rabbit sera antibodies produced to interspecific types of cells to bind to mouse trophectoderm antigens and mediate complement-reactive lysis was investigated. Fifty hatched and 25 expanded blastocysts per treatment were exposed to 1 of 7 heat-inactivated polyclonal antibodies (1: 10 DMEM dilution) produced in rabbits to mouse brain cells (MBr), mouse lymphocytes (MLy), rat lymphocytes (RLy), hamster lymphocytes (HLy), cattle splenocytes (CSp), sheep splenocytes (SSp), and pig splenocytes (PSp). After subsequent incubation in a guinea pig complement solution (1: 16 dilution) the embryos were assessed for trophectoderm lysis, and the inner cell masses were pipetted free of cellular debris. Fewer (P<0.01) hatched blastocysts were lysed completely when treated with RLy (60%), CSp (50%) and PSp (14%) antibodies compared the other treatment groups (100%). A similar response was observed with expanded blastocysts, with the exception that even fewer (P<0.01; RLy, 24%; CSp, 40%; PSp, 0%) were lysed completely. Forty percent of the PSp expanded blastocysts experienced no lysis, which was different (P<0.01) than in all the other treatments. Secondary experiments were performed to explain the cause of partial lytic response. Overall, the results indicate that interspecific antibodies can bind to murine trophectoderm surface antigens and mediate immunosurgical inner cell mass isolation, although the trophectoderm lytic response varied with antibody source.

Journal Article↗
PubMed1991

[Persistent B-cell polyclonal lymphocytosis: a benign lymphoproliferative syndrome].

A further case of persistent polyclonal B-cell lymphocytosis is reported. This recently identified distinct clinicopathologic entity is frequently associated with the presence of the HLA-DR7 antigen. It follows a benign course and has so far been reported only in women smokers. The disorder is characterized by mild chronic peripheral lymphocytosis, the presence of characteristic binucleate lymphocytes on peripheral blood smears, and a polyclonal increase in serum IgM. In some cases, lymphadenopathies and/or splenomegaly are observed. Surface marker studies of peripheral lymphocytes demonstrate the polyclonal B-cell nature of this entity.

Adult↗
PubMed1991

Dysmegakaryopoiesis predicting response to therapy in acute myeloid leukaemia. A histologic and clinical study.

With standard induction therapy between 50 to 85% of patients with Acute Myeloid Leukaemia (AML) achieve Complete Remission (CR). We investigated whether any morphological feature of bone marrow (BM) plastic embedded biopsies could predict failure of therapy. We reviewed BM plastic embedded biopsies from 54 adult patients presenting with untreated AML. The main histologic parameters analysed were cellularity, dysmegakaryopoiesis (DysM), percentage of marrow blasts and fibrosis. CR was obtained in 34 of 49 treated patients (69%). The rate of CR was significantly lower in the group of patients presenting with DysM: CR was achieved in 54% of the 28 treated patients with DysM and in 90% of the 21 treated patients without DysM (p less than 0.02). Patients with DysM had a significantly lower blood count and bone marrow blasts at presentation. Median age was not significantly different in the 2 groups. Cellularity and fibrosis were not predictive. DysM may be the hallmark of an AML subgroup with distinct clinical behaviour and lower rate of CR with conventional therapy. DysM should be carefully looked for on BM marrow biopsies and aspirate from AML patients at diagnosis.

Acute Disease↗
PubMed1990

[Visceral leishmaniasis (kala-azar) and HIV infection. Apropos of a case and literature review].

A 42 year old male Spanish patient who presented since one year a symptomatic stage IV C1,C2,D HIV infection (Pneumocystis carinii pneumonia, cerebral toxoplasmosis, esophageal candidiasis, Kaposi's sarcoma) became progressively asthenic with weight loss, diarrhea, fever and complained about bone pain. These symptoms could be attributed to visceral leishmaniasis. This novel opportunistic infection should be considered in the differential diagnosis of fever of unknown origin in HIV+ patients coming from or having travelled in endemic areas.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Cytogenetic analysis of 54 cases of myelodysplastic syndrome.

Fifty-four patients with myelodysplastic syndrome (MDS) (35 men and 19 women aged 34-92 years) were studied cytogenetically. Bone marrow cell culture and chromosome preparation were performed according to four different protocols used in parallel: methotrexate (MTX)-synchronized or thymidine (TdR)-unsynchronized techniques, and presence or absence of 5637 conditioned medium (CM). Some patients responded better to MTX; others had better results with TdR exposure only. Use of 5637 CM generally improved quantity and quality of metaphases. A cytogenetic result was obtained in 53 cases. 60% of the patients had a chromosome abnormality. Percentage of abnormality varied from one French-American-British (FAB) subtype to the other: 62% in refractory anemia with ringed sideroblasts (RARS, 8/13), 50% in refractory anemia (RA, 6/12), 60% in refractory anemia with excess of blasts (RAEB, 3/5), 77% in refractory anemia with excess of blasts in transformation (RAEB-T, 7/9), and 57% in chronic myelomonocytic leukemia (CMMoL, 8/14). Chromosome defects were subdivided into three categories: single, two, and complex defects. The most frequent chromosome abnormalities, either single or one of two or complex defects were del(5q) or monosomy 5 (13 cases), trisomy or rearrangement of chromosome 8 (eight cases), total or partial monosomy or rearrangement of chromosome 7 (eight cases), Y loss (seven cases), and del(20q) (two cases). With the exception of del(5q) in macrocytic RA, this study confirms the absence of chromosome defects specific to each FAB category of MDS. Recurrent defects in MDS are relatively limited, however, in terms of chromosomes involved and type of abnormality. Consequently, these defects, mostly of deleted type, are assumed to play a specific role in the genesis of myelodysplasia.

Adult↗
PubMed1990

The individual over time: time series applications in health care research.

This paper presents a summary and a brief theoretical introduction to time series ARIMA modeling of single subject data. Time series, a statistical technique that may be appropriate when data are measured repeatedly and at nearly equal intervals of time, has potential research applications in the study of chronic diseases such as diabetes, hypertension, and herpes simplex. Both intervention models and multivariate models are covered, with examples illustrating the utility of time series techniques in chronic disease research. Time series modeling of a subject with diabetes before and after being placed on a regimen of chlorpropamide is used to demonstrate the potential of intervention analysis. Multivariate time series techniques are illustrated by modeling the relationship between exercise and blood glucose, and by modelling the relationship between psychosocial distress and lymphocyte subsets of the cellular immune system.

Blood Glucose↗
PubMed1989

Pregnant mares' serum gonadotropin source influences fertilization and fresh or thawed embryo development, but the effect is genotype specific.

The influence of the source of pregnant mares' serum gonadotropin (PMSG) on the number, quality, and in vitro development of mouse embryos before and after freezing was evaluated among three genotypes: N:NIH(S), C57BL/6N, and C3H/HeN-MTV-Immature females were given PMSG from one of five commercial sources. Following collection (116 hr later), embryos were evaluated for stage of development, and four- to eight-cell embryos were pooled within genotype and assigned to standardized fresh or freeze-thaw culture trials. Different PMSG sources stimulated the production of different numbers of total embryos (P less than 0.05) but not necessarily more embryos suitable for freezing. Differences in embryo production among genotypes indicated that absolute embryo numbers using a single mouse genotype may not accurately reflect the potency of a specific gonadotropin source. The PMSG source also affected the ability of an embryo to survive in culture either immediately after collection or after frozen storage. The effect, however, was genotype specific, with some mouse strains being relatively insensitive to PMSG source, whereas gonadotropin source played a major role in determining in vitro viability in others. Development rates for freshly collected embryos differed, often inconsistently, from those of thawed embryos regardless of the PMSG source used, demonstrating that fresh embryo development cannot be used to estimate expected post-thaw survival. In vitro development of thawed embryos is influenced not only by genotype, but also the source of the gonadotropin used to promote follicular development and oocyte maturation. These findings may explain, in part, the wide variation in embryo viability and culture rates reported among laboratories and intraspecies animal populations.

Animals↗