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H Ludwig

Publications and source records attributed to H Ludwig.

At least 37 records · Page 2Linked to original sources
PubMed2002

Influence of activation and germination on high pressure inactivation of ascospores of the mould Eurotium repens.

We investigated heat activation and germination of Eurotium repens ascospores to follow high pressure inactivation. Activation energy and entropy values strengthen the idea of protein denaturation as the underlying mechanism of heat activation. Preceding activation, germination or a combination of both affected high pressure inactivation in different ways. Activation followed immediately by high pressure treatment led to the most efficient improvement in inactivation. However, a pause after activation caused a partial re-establishment of the spores' stability and less efficient high pressure inactivation. Germination stabilized the spores against high pressure. A combined treatment of activation and germination led to an initially fast inactivation, but compared to high pressure treatment of only activated spores the time course of inactivation was slowed down.

Ascomycota↗
PubMed2002

[Obstetrics and gynecology--retrospect of 125 years in Basel].

The development of the discipline Obstetrics and Gynecology is reflected by the medical history at the University of Basel. At the very beginning of academic obstetrics, the cantonal government realised the need of a more practical teaching completing the tradition of theoretical lecturing (1865). Obstetrics was (and still is) a typical example for the turn from theoretical to hands-on-teaching in medicine. At the time, when the independent chair of obstetrics at the University of Basel was founded (1867, Bischoff [1841-1892]), the fight against puerperal fever was the most urgent aim. The battle against puerperal fever was ultimately won around the turn of the 19th to the 20th century (von Herff [1856-1916]) but not much earlier. Step by step the gynecology grew out of the classical surgery where it has been located previously. Surgically skilled obstetricians like Fehling [1847-1925] and Bumm [1868-1925] have enhanced that development. Clinical research started with better information about the lying-in patients (Fehling, Bumm, Labhardt). Bacteriology in close connection with obstetrics was seen important (Bumm). Some decades later, clinical laboratories (clinical chemistry) were founded accompanying the diagnostic approach to various disorders of pregnancy (Labhardt [1874-1949]). Exfoliative cytology became mandatory since 1950 and this was the start to screening programs for early diagnosis of cervical cancer (Koller [1899-1985]). The family planning exploded in the years from 1965 on as the pill has been available, replacing sterilisation-procedures (Labhardt). Endocrinology of pregnancy and cycle needed new biochemical methods. The laboratories were installed. Responding to the demands of a growing discipline, the building was enlarged and adapted in three major steps: 1896 new "Frauenspital", 1928 first enlargement, 1956-1968 constructing of two more storeys, of new surgical theatres and an entire tract for routine and scientific laboratories filling now the area between Klingelberg-, Schanzen- and Spitalstrasse. The hospital harboured in its peak time (1968-1970) more than 300 beds. In 1959 the hospital staff took care of 5000 deliveries (Koller). Fetal monitoring was introduced 1962, being the starting point for the development of "fetal medicine" in Basel. At that time, Otto Käser [1899-1995] was chairman. He was appreciated as one of the most brilliant pelvic surgeons in Europe. Soon, the surgery for breast cancer was added to the classical gynecologic surgery. At the same time, ultrasound started to dramatically influence diagnostic procedures in pregnancy. In the eighties, in-vitro-fertilization and embryo-transfer improved the possibilities to overcome unwanted childlessness (Ludwig [*1929]) and supplemented endocrinology. The scientific spectre spread heavily to reproductive medicine since then, in particular to the molecular biology and research on stem-cells, which was introduced by the present chairman (Holzgreve [*1955]). He has founded several research groups concentrating on the retrieval of floating fetal cells from cord and maternal blood, on other topics in fetal cell research, prenatal diagnosis and in ultrasound.

Female↗
PubMed2002

A paraneoplastic syndrome mimicking extrauterine pregnancy.

We report on a 30-year-old female patient with a beta-human chorionic gonadotropin (beta-HCG)-producing lung tumour. Abdominal discomfort and vaginal bleeding were the presenting symptoms and, in conjunction with elevated beta-HCG levels, initially led to the diagnosis of extrauterine pregnancy. Bilateral ovarian cysts were detected on further diagnostic workup. Ultimately, a chest X-ray revealed a lung tumour. The paraneoplastic symptoms were completely reversible after resection of the lung lesion, and the ovarian cysts disappeared.

Adult↗
PubMed2001

Detection of equine herpesvirus type 2 (EHV-2) in horses with keratoconjunctivitis.

The prevalence of EHV-2 in 27 horses with keratoconjunctivitis and 21 clinically healthy horses of different ages and stocks were analyzed. We demonstrated that EHV-2 was present in 12 keratoconjunctivitis cases as shown by nested PCR on ocular swabs. This is statistically more often than in the control group, where only two ocular swabs were EHV-2 positive. Cocultivation was successful on peripheral blood leukocytes of healthy and diseased horses but not on swabs. We isolated ten EHV-2 strains from diseased and nine from control horses, whereas 16 isolates showed different restriction enzyme patterns. The results of immunfluorescence and neutralization tests are predictory only in combination with the nested PCR data on ocular swabs. A successful antiviral treatment in nine out of 16 cases supports the aetiological role of EHV-2 in this ocular disease.

Animals↗
PubMed2001

The Bacillus subtilis catabolite control protein CcpA exerts all its regulatory functions by DNA-binding.

In Bacillus subtilis, carbon catabolite control is mediated by the regulatory protein CcpA. In addition to loss of catabolite repression, ccpA mutants exhibit a severe growth defect. They are not able to grow with glucose and ammonium as single sources of carbon and nitrogen, respectively. Only ccpA mutant strains carrying either secondary suppressor mutations or that are affected in specific amino acids in the DNA-binding domain of CcpA grow on minimal media. We addressed the importance of DNA-binding by CcpA for both carbon catabolite repression and growth of a mutant strain. A strain specifically deleted for the N-terminal DNA-binding domain of CcpA was constructed. This deletion resulted in complete loss of catabolite repression of beta-xylosidase synthesis and prevented bacteria from growing on minimal media, suggesting that DNA-binding by CcpA is required for both carbon catabolite repression and efficient growth on minimal media.

Alleles↗
PubMed2001

Clp-mediated proteolysis in Gram-positive bacteria is autoregulated by the stability of a repressor.

The heat shock proteins ClpC and ClpP are subunits of an ATP-dependent protease of Bacillus subtilis. Under non-stressed conditions, transcription of the clpC and clpP genes is negatively regulated by CtsR, the global repressor of clp gene expression. Here, CtsR was proven to be a specific substrate of the ClpCP protease under stress conditions. Two proteins of former unknown function, McsA and McsB, which are also encoded by the clpC operon, act as modulators of CtsR repression. McsA containing zinc finger motifs stabilizes CtsR under non-stressed conditions. McsB, a putative kinase, can inactivate CtsR by modification to remove the repressor from the DNA and to target CtsR for degradation by the ClpCP protease during stress. Thus, clp gene expression in Gram-positive bacteria is autoregulated by a novel mechanism of controlled proteolysis, a circuit of down-regulation by stabilization and protection of a transcription repressor, and induction by presenting the repressor to the protease. Thereby, the ClpC ATPase, a member of the Hsp100 family, was identified as a positive regulator of the heat shock response.

Adenosine Triphosphatases↗
PubMed2001

Serum bone sialoprotein as a marker of tumour burden and neoplastic bone involvement and as a prognostic factor in multiple myeloma.

To test the potential of immunoreactive BSP, a non-collagenous bone matrix component, as a clinical guide in patients with plasma cell dyscrasias, serum BSP concentrations were measured in 62 patients with newly diagnosed multiple myeloma (MM) followed over a period of 4 years, in 46 patients with monoclonal gammopathy of undetermined significance (MGUS), in 71 patients with untreated benign vertebral osteoporosis (OPO), and in 139 healthy adults. Results were compared with clinical and laboratory data, including serum osteocalcin (OC), and urinary pyridinoline (PYD) and deoxypyridinoline (DPD) as markers of bone turnover. In MM, serum BSP, and urinary PYD and DPD were higher than in healthy controls and in MGUS or OPO (P< 0.001). BSP levels correlated with the bone marrow plasma cell content (r = 0.40, P< 0.001), and serum beta2-microglobulin (r = 0.31, P < 0.01). The differentiation of MM from healthy controls and from MGUS or OPO was highest for BSP. After chemotherapy, BSP reflected the response to treatment and correlated with the change in monoclonal protein (r = 0.55, P< 0.001). MM patients with normal baseline BSP levels survived longer than patients with initially elevated BSP values (P< 0.001, log rank test). Only serum monoclonal protein and BSP were independent predictors of survival. We conclude that in MM, BSP levels are associated with skeletal involvement and tumour cell burden. The quantification of serum BSP may be a non-invasive method for the diagnosis and follow-up, and may improve the prognostic value of conventional staging in MM.

Adult↗
PubMed2001

Absence of clonal chromosomal relationship between concomitant B-CLL and multiple myeloma--a report on two cases.

B-cell chronic lymphocytic leukemia (B-CLL) and multiple myeloma (MM) are chronic B-cell malignancies that represent different stages of B-cell maturation. Occasionally, both diseases are present in the same patient, and this raises the question of clonal associations between the two neoplasms. We here report on two patients with concomitant B-CLL and MM. Clonal chromosomal abnormalities in both lymphocytic cells and plasma cells were studied by interphase fluorescence in situ hybridization (FISH) using a panel of 24 chromosome- and region-specific DNA probes. In the first patient, cytogenetics revealed 47, X, t(Y;22)(p11;q10), +12, dell4(q21q32). By FISH, +12 was present in lymphoid cells, but not in plasma cells. MM cells were characterized by multiple chromosomal gains (1, 11q23) and losses (5q, 10, 13q14, 15, 17p13, Y), which were all undetectable in lymphoid cells. The second patient, in whom no clonal abnormalities were obtained by conventional cytogenetic analysis, had lymphoid cells with loss of 8q24 by FISH. In contrast, evidence for a gain of 8q24 (consistent with amplification of c-myc) was obtained in 13% of plasma cells. Plasma cells were further characterized by gains of chromosomes 1, 3, 11, 18, and Y. We thus conclude that this comprehensive molecular cytogenetic analysis demonstrates the existence of two clonally distinct B-cell malignancies in both patients.

Aged↗
PubMed2001

[Retinoscopy. A multi-media teaching program on CD].

INTRODUCTION: Retinoscopy is a classical method to determine the refraction of the eye by observing the dynamics of reflexes and varying the experimental parameters until a specific reflex (neutralisation point) is observed. Until now photographs and geometrical drawings of the different ray tracings have been commonly used to visualise the pathways. We intend to use new media such as video and CD to offer the students a better understanding of retinoscopy. METHODS: With the aid of appropriate experimental devices, retinoscopal reflexes of artificial and human eyes are recorded on video. The video sequences are converted in computer files and together with computer animations of the geometrical ray tracings, text files and audio sequences, they are stored in a suitable CBT-programme. RESULTS: The systematically prepared computer compatible contents offer a modern individually controllable method to perform the instruction programme by multimedia. The CBT-program and the specific files are stored on CDs or can be distributed on the internet. A collection of retinoscopy records of patients, some with extraordinary reflex phenomena is also available. DISCUSSION: Video and animation procedures are more suitable for matching the dynamic phenomena on retinoscopy than photographs or drawings as they offer a more direct basis for understanding of the sometimes difficult processes of retinoscopy. The collection of recorded reflexes also offers the direct visualised experience of particular patient findings such as the appearance in context of implanted spherical and aspherical intraocular lenses or the irregularities of the optic system of eyes with keratokonus.

Computer-Assisted Instruction↗
PubMed2001

Symptomatology of anemia.

The symptoms and severity of anemia depend on various factors, including the degree of anemia, the rapidity of its onset, and the age and physiologic status of the patient. Although the human body tries to counterbalance the effects of anemia by various mechanisms, almost every organ system of the human body is eventually affected. The symptoms experienced by patients vary from cold skin, dizziness, and palpitations to pulmonary edema, heart failure, depression, and severe impairment of cognitive function. Anemia substantially impacts patients' quality of life, a fact that has been shown in several clinical trials in patients with renal disease as well as in patients suffering from various malignancies undergoing chemotherapy. These studies evaluated the administration of recombinant human erythropoietin (r-HuEPO, epoetin alfa) to anemic patients, and it was shown that raising hemoglobin levels with epoetin alfa ameliorated the symptoms of anemia and significantly improved the functional status and overall quality of life in cancer patients. Furthermore, preliminary data indicate that the correction of anemia in cancer patients may in addition improve treatment efficacy and possibly overall survival.

Anemia↗
PubMed2001

Reversibility of high pressure effects on the contractility of skeletal muscle.

High pressure application has been extensively used to thermodynamically influence complex physiological processes such as membrane ion conductances and the mechanism of muscle contraction. However, little is known about the reversibility of high pressure effects on intact cells. Therefore, we studied the reversibility of 3 h pressure applications up to 25 MPa at +4 degrees C to intact murine skeletal muscle. Functional mechanical properties were tested in extensor digitorum muscle fibres skinned following a high pressure exposure. Calcium activated force and stiffness were nearly unchanged following pressure applications up to 20 MPa, whereas for higher pressures we found a marked reduction of peak force, a decline of activation kinetics, an increase of relaxation stiffness but still unchanged peak stiffness. The rigor kinetics showed a similar behaviour as the activation kinetics. pCa-force relations remained unchanged up to 20 MPa but were shifted towards smaller pCa values for higher pressures. In conclusion there is a rather sharp high pressure limit of 20 MPa above of which pressure application results in a substantial irreversible loss of contractile functionality in differentiated muscle which may at least partly be explained by changes in the Ca2+ regulatory process. This is supported by a degradation of the 37 kDa band, i.e. Troponin T, shown by SDS gel electrophoresis. However, the general stability of the other bands does not indicate a substantial increase of unspecific protease activity following a high pressure treatment up to 25 MPa.

Animals↗
PubMed2001

Borna disease virus-specific circulating immune complexes, antigenemia, and free antibodies--the key marker triplet determining infection and prevailing in severe mood disorders.

Borna disease virus (BDV), a unique genetically highly conserved RNA virus (Bornaviridae; Mononegavirales), preferentially targets neurons of limbic structures causing behavioral abnormalities in animals. Markers and virus in patients with affective disorders and schizophrenia have raised worldwide interest. A persistent infection was suggestive from follow-up studies, but inconstant detectability weakened a possible linkage.This study for the first time discloses that detection gaps are caused by BDV-specific circulating immune complexes (CIC), and their interplay with free antibodies and plasma antigens (p40/p24). Screening 3000 sera each from human and equine patients over the past 4 years by new enzyme immunoassays (EIAs) revealed that BDV-CICs indicate 10 times higher infection rates (up to 30% in controls, up to 100% in patients) than did previous serology. Persistence of high amounts of CICs and plasma antigens correlates with severity of depression. Even BDV RNA could be detected in plasma samples with strong antigenemia. Our discovery not only explains the course of persistent infection, but offers novel easy-to-use diagnostic tools by which new insights into BDV-related etiopathogenesis of disease and epidemiology are possible.

Adult↗