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Sibling risks in cancer: clues to recessive or X-linked genes?

A systematic analysis of cancer risks to offspring and to siblings of cancer cases was carried out based on the nation-wide Swedish Family-Cancer Database. For all 13 cancer sites examined, risks to both offspring and siblings of cases of cancer at the same site were significantly elevated. The relative risk to siblings was approximately 2 fold more than the offspring risk for cancers of the prostate, testis, kidney and bladder, suggesting that recessive or X-linked susceptibility genes may be important for these cancers. Risks to siblings of cases where a parent was also affected were increased >20 fold over population rates for colorectal, ovarian, prostate and renal cancer, and for leukaemia, consistent with the effects of rare high-risk susceptibility alleles.

Family Health↗

Optimization of electroporation conditions for Mycobacterium avium.

Successful transformation and subsequent genetic manipulation of Mycobacterium avium requires suitable vectors, efficient transformation systems, and reliable selectable markers. A systematic analysis of the parameters involved in the transformation of M. avium was performed to optimize DNA transfer. Factors examined included the composition of the growth medium, growth medium additives, variations in washing of the bacteria prior to electroporation, and conditions of electroporation. Of the parameters assayed, the frequency of transformation (defined as the number of transformants per 10(6) transformed bacteria) showed the greatest increase with the addition of 1.5% glycine to the M. avium culture medium and the use of higher concentrations of plasmid DNA. The addition of 0.5 M sucrose to the growth medium and wash solution yielded a modest increase in transformation frequency, but more importantly afforded greater consistency of results between different batches of cells with no decrease in transformation yields following freezing and thawing. We also confirmed that gfp could be used as a selective marker for M. avium, even as a single copy integrant, and allowed for rapid discrimination between false and true transformants. Using this protocol, we were able to transform nine of 11 clinical strains of M. avium.

Culture Media↗

[Gynaecomastia and mammography (author's transl)].

The term gynaecomastia indicates an increase in the mass of the normally rudimentary male breast; morphologically there is hyperplasia and differentiation of the epithelial and mesenchymal breast components. Gynaecomastia is not a disease in itself, but a symptom of some underlying disease or the result of drugs. Of 2895 breast operations performed at the surgical clinic of the University of Göttingen, 2.97% were operations on men with gynaecomastia. Amongst 79222 mammograms in the Radiological Clinic of the University, there were 900 mammograms (1.14%) of 392 men with gynaecomastia. Most benign and malignant conditions in men are retromammary in localisation. For this reason clinical evaluation is frequently wrong. The use of mammography as an additional diagnostic method in men is therefore more important than it is in women. Systematic analysis of the mammograms performed on men has made possible a classification of gynaecomastia according to the radiological appearances: I Septal linear structures (8.5%), II Opacities of varying density and size (26.5%), III Circular, usually inhomogenous shadows (15.5%), IV Homogeneous, demarcated foci of varying size (35.5%), V Soft-tissue hyperplasia-pseudo-gynaecomastia (10%).

Adolescent↗

Therapeutic and operational profiles of metrifonate and praziquantel in Schistosoma haematobium infection.

A systematic analysis of the existing literature has been undertaken to compare the therapeutic and operational profiles of metrifonate (CAS 52-68-6), and praziquantel (CAS 55-268-74-1), two anti-schistosomal compounds. The criteria evaluated were therapeutic efficacy against Schistosoma haematobium and other helminths, impact on pathology commonly associated with S. haematobium infection, frequency, type and duration of adverse reactions, health risk associated with inadvertent overdosage, applicability and practicality of treatment in various medical settings, tolerance and resistance, pharmacological properties, toxicity and economic aspects. It is concluded that both medical and operational criteria indicate that praziquantel is superior to metrifonate for the treatment of schistosomiasis caused by S. haematobium. Since, compared to praziquantel, metrifonate has a number of disadvantages, future antischistosomal chemotherapy can do without this drug.

Animals↗

[Chronic diseases, psychological distress and coping -- challenges for psychosocial care in medicine].

Due to the increase of chronic diseases within the last decades the need and demand for psychosocial treatment in medicine has been realized. This review focuses on the psychosocial aspects of chronic diseases and discusses selected topics of medical and rehabilitation psychology. Recent developments in quantitative and qualitative methods have allowed the systematic analysis of psychosocial distress and coping with chronic disease as well as the consequences on social relationships. The need for psychosocial treatment in acute care and rehabilitation can be diagnosed by differential assessment tools for coping and psychiatric morbidity. Specific approaches of psychology and psychotherapy for patients with somatic diseases have been developed and may be regarded as an integrative part of medical treatment in acute care and rehabilitation. In rehabilitation, the traditional individualistic view of psychotherapy has been broadened towards vocational integration and participation in social activities as outcome criteria. Evaluation research as well as the rehabilitation sciences have provided empirical data on psychosocial treatment of chronically ill patients. Under increasing financial restrictions and problems of the health care systems there is a need for quality assurance and the proof of scientific evidence to guarantee psychosocial treatment as an integrated part of medical care in the future.

Adaptation, Psychological↗

[Compulsory admission of mentally ill patients in European union member States].

AIMS: A standardised and systematic analysis of commitment laws in the EU-Member States is still missing. This study aimed at gathering, describing and analysing information on the differences or similarities of legal frameworks for involuntary placement and treatment of mentally ill patients across the European Union Member States. METHOD: Information was gathered by means of a detailed questionnaire filled in by experts from all EU Member States. Legal criteria for compulsory admission, details of the assessment and decision process of compulsory admission and epidemiological data are outlined. RESULTS: Although common patterns among Member States can be identified upon comparison of crucial legislative or procedural details, these patterns are far from being consistent across all analysed items or approaches. With regard to compulsory admission quotas no significant influence of legal commitment criteria and the involvement of judicial authorities could be found but Member States with an obligatory inclusion of a legal representative during the commitment procedure showed significantly lower compulsory admission quotas. CONCLUSION: Results of this study show the strong necessity for further research in this field. Common international health reporting standards as annually updated involuntary placement rates detailed for regular and emergency cases seem to be essential.

Commitment of Persons with Psychiatric Disorders↗

Clozapine in the treatment of obsessive-compulsive symptoms in schizophrenia patients: a case series study.

INTRODUCTION: Obsessive-compulsive (OC) symptoms have been observed in a substantial proportion of schizophrenic patients. There are some reports describing the appearance de novo or reemergence of preexisting OC symptoms under clozapine (CLZ) therapy. However, there are also reports describing a positive effect of CLZ therapy in OC schizophrenic patients. It seems that comorbid OC symptoms are common among CLZ-treated refractory schizophrenic patients and are likely to be an integral part of their illness. The complex nature of the treatment response in this group of schizophrenic patients is as yet unclear. The effects of CLZ on OC symptoms may vary, with evidence of improvement in some and worsening among others. METHODS: The present case series study describes our experience with CLZ as a sole agent (n = 10) or in combination with serotonin reuptake inhibitors (n = 5), in schizophrenic patients with prominent OC symptomatology. RESULTS: Systematic analysis of clinical features of our patients, as well as findings in the literature to date, led us to suggest some factors that may predict response to CLZ treatment in treatment-resistant schizophrenic patients with prominent OC symptoms: 1) schizophrenic patients who began to exhibit OC symptoms within the course of the psychotic process need and might to be successfully treated with CLZ alone; 2) when OC symptomatology preceded the development of schizophrenic process, CLZ monotherapy is inefficient and may even worsen OC symptoms; therefore, it should be treated concomitantly with specific anti-obsessive agents; 3) in both groups there is a definite dose-related pro-obsessive influence of CLZ when it is given in high doses. DISCUSSION: Further controlled investigations in a larger cohort of OC schizophrenic patients are needed to substantiate our hypothesis. OCD:Obsessive-compulsive disorder OCS:Obsessive-compulsive symptoms SRI:Serotonin reuptake inhibitors

Adult↗

Stress fractures in the juvenile skeletal system.

Stress fractures affecting the juvenile skeletal system are rare and are described as having a good prognosis. Precisely because these fractures are so rare, studies allowing clear and generally applicable conclusions are lacking. The object of the present study was a systematic analysis of patients with stress fractures in an immature skeletal system, with special reference to the frequently difficult and delayed diagnosis and to the forms of therapy considered appropriate. Twenty-five patients with a total of 27 stress fractures affecting bones with the growth plates still open were examined according to a standardized procedure. The average duration of follow-up was 4.8 years (SD +/- 2.3) and the average age at occurrence 12.9 years (SD +/- 4.31). The risk factors were largely the same as those in adults. The most frequent site was the tibia (48% of cases; n = 13), followed by the metatarsal bones. Most (26/27) fractures were treated conservatively, with an average duration of therapy of 8.9 weeks (SD 8.2 weeks). Ultimately, 17 (63%) of the fractures healed in such a way as to allow the patients to return to full athletic activity with no restrictions within 3 months after diagnosis. In 9 cases (33%) it was not possible to achieve complete absence of symptoms within 12 months after diagnosis was made. No pseudarthroses were observed. There was a significant correlation between clinical outcome recorded as "free of symptoms" and an early diagnosis (less than 2 weeks after first symptoms (p = 0.033) and a fracture line seen on MR tomography in contrast to a stress reaction with merely increased signal intensity (p = 0.037). Overall, a strikingly high proportion of these patients had a prolonged course. This is attributable partly to the delay in diagnosis and to inappropriate initial treatment. When stress fractures were recognizable by a demonstrable fracture line--in contrast to just an edema--on MR tomography and their diagnosis was followed by an adequate form of therapy the chances of complete healing seemed to be better. It is essential to carry out targeted imaging investigations, e.g., by means of MR tomography, when there is a reason to consider a stress reaction. Furthermore, stress fractures should be adequately treated until all symptoms have disappeared.

Adolescent↗

[Do estrogens have an antipsychotic action?].

Within the framework of our ABC study, an epidemiological study on schizophrenia (Häfner et al., 1989, 1991 a; Riecher et al., 1991), we were able to show that the mean age at onset of the disease is 3-4 years higher in women than in men and that women have a second peak of onsets after 45 years of age. In a systematic analysis we developed and tested different psychosocial and biological explantory hypotheses. The oestrogen hypothesis could be identified in the course of this analysis as the most plausible one. According to this hypothesis (Häfner, 1987) female sex hormones enhance the vulnerability threshold for schizophrenia. In this case women from puberty to (pre-)menopause would be protected from the outbreak of the disease to a certain extent by their high physiological oestradiol production; they would, however, later "draw level" in respect of morbidity risk. Animal experiments conducted to test this hypothesis and to explain the underlying pathophysiological mechanism implied that oestradiol can modulate the sensitivity of dopamine-D2-receptors in the brain (Häfner et al., 1991 b; Gattaz et al., 1992). In the clinical study presented, we examined the validity of the oestrogen hypothesis in humans. We tested, whether the acute symptomatology of schizophrenic patients fluctuates with oestradiol serum levels during the female menstrual cycle. We examined 32 acutely admitted schizophrenic women during their hospital stay by analysing hormonal parameters and applying various rating scales for psychopathology on certain days of the cycle. A significant association emerged between oestradiol levels on the one hand, and psychiatric symptomatology, behaviour on ward, paranoid tendencies and general well-being, on the other.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Parastomal tumors after laryngectomy: etiology and therapy].

BACKGROUND: Parastomal neoplasm after total laryngectomy for laryngeal carcinoma represents an extremely serious complication and one of the most formidable therapeutic problems encountered by the head and neck surgeon. Studies about the etiology of parastomal neoplasm have been controversial. The factors most strongly implicated in parastomal neoplasm have been recurrence spawned by metastases to deep cervical lymph nodes, undetected neoplasm at the margin of the laryngectomy resection, neoplastic cell implantation by pre-operative tracheotomy, and the development of an additional primary. PATIENTS: To clarify the controversial aspects of parastomal neoplasm etiology, a systematic analysis of parastomal neoplasm after laryngectomy was performed using data from 10 patients who developed parastomal neoplasm. RESULTS: Parastomal neoplasm occurred in 7.9%. The tumor site of the primary laryngeal carcinoma was found in 9/10 cases in the subglottic, supraglottic, or transglottic area. These tumor sites correlate with areas of a lymphatic vessel concentration and an increase of intralaryngeal lymphatic drainage. In average the parastomal neoplasms appear 10.3 months after the laryngectomy. Therapy was unsuccessful in spite of extensive surgical interventions. CONCLUSIONS: If the laryngeal carcinoma was resected with margins of healthy tissue, lymphatic metastasis to the pretracheal and paratracheal cervical lymph nodes is the probable cause of parastomal neoplasm. This could be the consequence of the continuous lymphatic drainage between the supraglottic and subglottic area with a midline crossing and an lymphatic outlet to the pretracheal and paratracheal cervical lymph nodes. The cervical metastasis formation cannot be detected due to the limitations in the assessment of small lymph nodes and the inability to ascertain with confidence the presence or absence of metastasis in any one lymph node in ultrasonography, computed tomography, and magnetic resonance imaging and due to the limitations in the removal of lymph nodes in the pretracheal and paratracheal area by means of a functional or radical neck dissection. The method of treatment should be in cases of a subglottic or a supraglottic laryngeal carcinoma an ipsilateral and contralateral pretracheal and paratracheal lymph node removal in combination with the laryngectomy.

Aged↗

[Uveal melanomas in patients less than 20 years of age].

During the past 15 years we observed 21 uveal tumors in patients aged 20 years and younger. Four of them were younger than 10 years, 4 were 11 to 15 years' old, 4 ranged from 16-17 years and 9 from 18-20 years. An accelerated beam irradiation was applied in 11 cases, a surgical excision was carried out in 4 cases, and a 60 CO-applicator used for 3 patients. Three enucleations were carried out straight away. In this study we present the clinical characteristics of melanomas of young people, the therapy used, as well as the systematic analysis of the vital prognosis of the patients and of the functional prognosis of the eyes under treatment.

Adolescent↗

[Occult papillary thyroid carcinoma. Clinical significance and morphology of a common tumor].

In a systematic analysis of surgical specimens of 388 carcinomas of the thyroid 34 occult papillary tumours were revealed. In 18 of the 34 patients cervical lymph-node metastases were demonstrated, which in 16 had been the indication for operation. In 15 patients the tumour was a chance finding in a thyroid resected for other reasons. Postoperative follow-up over an average of ten years demonstrated a uniformly favourable course in all, regardless of tumour size or type, age, sex or lymph-node status. There were no local recurrences or metastases beyond those known at time of thyroidectomy.

Adult↗

A theoretical model of the photoabsorption spectra of carbon buckyonions.

A theoretical model has been developed to predict the photoabsorption spectra of spherical carbon buckyonions in the region dominated by the pi-plasmon feature. This model makes use of the microscopic electronic structure of the system, which is provided by an effective Huckel one-electron model. The important screening effects are treated within the random phase approximation, whose form is an extension to the dynamic case of the one derived in a previous work for the static polarizabilities of these species. A systematic analysis as a function of the buckyonion size is performed. We compare the spectra obtained in this way with those derived from a different representation of the electron motion, namely a two-dimensional spherical electron gas, and from a classical dielectric model.

Journal Article↗

Dopant distribution in a Tm(3+)-Yb(3+) codoped silica based glass ceramic: an infrared-laser induced upconversion study.

The optically active dopant distribution in a Tm(3+)-Yb(3+) doped silica based glass ceramic sample has been investigated. A systematic analysis of the upconversion fluorescence of the Tm(3+)-Yb(3+) codoped glass and glass ceramic has been performed at room temperature. Tm(3+) and Yb(3+) single doped glass and glass ceramics have also been included in the study. Upon infrared excitation at 790 nm into the (3)H(4) level of the Tm(3+) ions a blue upconversion emission is observed, which is drastically increased in the Yb(3+) codoped samples. A rate equation model confirmed the energy transfer upconversion mechanism. Based on these results, the temporal dynamic curves of the levels involved in the upconversion process, (3)H(4), (2)F(5/2), and (1)G(4) were interpreted in the glass ceramic samples. The contribution of the optically active Tm(3+) and Yb(3+) ions in the crystalline and in the vitreous phase of the glass ceramic was distinguished and the ratio of Tm(3+) ions in the crystalline phase could be quantified for the 1 mol % Tm(3+)-2.5 mol % Yb(3+) glass ceramic. A surprising result was obtained for that concentration: the main contribution to the upconversion emission of the glass ceramic is due to Tm(3+)-Yb(3+) ions in the vitreous phase.

Journal Article↗

High-resolution millimeter wave spectroscopy and multichannel quantum defect theory of the hyperfine structure in high Rydberg states of molecular hydrogen H2.

Experimental and theoretical methodologies have been developed to determine the hyperfine structure of molecular ions from detailed studies of the Rydberg spectrum and have been tested on molecular hydrogen. The hyperfine structure in l=0-3 Rydberg states of H2 located below the X 2Sigmag+(v+=0,N+=1) ground state of ortho H2+ has been measured in the range of principal quantum number n=50-65 at sub-MHz resolution by millimeter wave spectroscopy following laser excitation to np and nd Rydberg states using a variety of single-photon and multiphoton excitation sequences. The np1(1), nd1(1), and the nf1(0-3) Rydberg states were found to be metastable and to have lifetimes of more than 5 micros beyond n=50. Members of other series, such as the nd1(2), nd1(3), and the np1(0) series, were found to have lifetimes of more than 1 mus. Local perturbations induced by low-n Rydberg states belonging to series converging on rovibrationally excited levels of H2+ reduce the lifetimes in narrow ranges of n values. The hyperfine structure is strongly dependent on the value of the orbital angular momentum l. In the penetrating s and p states at n approximately 50 the exchange interaction dominates over the hyperfine interaction and the levels can be labeled by the total electron spin angular momentum quantum number S (S=0 or 1). In the less penetrating d and f Rydberg states, the hyperfine interaction between the core nuclear and electron spins is larger than the exchange interaction and the Rydberg states are of mixed singlet and triplet character. A procedure based on the Stark effect and on the systematic analysis of selection rules and combination differences was developed to determine the orbital and the total angular momentum quantum numbers l and F and to construct an energy map of p and f Rydberg levels between n=54 and 64 with relative positions of an accuracy of better than 1 MHz. Multichannel quantum defect theory (MQDT) was extended to treat the hyperfine structure in molecular Rydberg states and was used to analyze the observed hyperfine structure of the p and f Rydberg states of H2. The frame transformation between the Born-Oppenheimer channels described by the angular momentum coupling scheme (abetaJ) and the asymptotic channels described by the (e[bbetaS+]) coupling scheme was derived and enables an elegant treatment of all intermediate coupling cases. Purely ab initio quantum defect theory reproduced the experimentally determined positions to within 40 MHz for the p levels and 13 MHz for the f levels. By slight adjustments of the quantum defect functions and their energy dependences and by consideration of the p-f interaction, of the singlet-triplet splittings of the f levels, and of the departure of the ionic levels from pure coupling case (bbetaS+), the agreement between theory and experiment could be improved to 600 kHz. By comparing the results of MQDT calculations of the hyperfine structure of f Rydberg levels with those of coupled equations calculations, the frame transformation approximation of MQDT was shown to be accurate to within 300 kHz. The extrapolated ionic hyperfine structure of the X 2Sigmag+(v+=0,N+=1) ionic level corresponds to the ab initio prediciton of Babb and Dalgarno [Phys. Rev. A 46, R5317 (1992)] within the experimental error.

Journal Article↗

1s22p3 and 1s22s23l, l = s,p,d, excited states of boron isoelectronic series from explicitly correlated wave functions.

For some members of the boron isoelectronic series and starting from explicitly correlated wave functions, six low-lying excited states have been studied. Three of them arise from the 1s(2)2p(3) configuration, and the other three from the 1s(2)2s(2)3l, l = s,p,d, configurations. This work follows a previous one on both the 1s(2)2s(2)2p-(2)P ground state and the four excited states coming from the 1s(2)2s2p(2) configuration. Energies, one- and two-body densities in position space and some other two-body properties in position and momentum spaces have been obtained. A systematic analysis of the energetic ordering of the states as a function of the total orbital angular momentum and spin is performed in terms of the electron-nucleus and electron-electron potential energies and the role of the angular correlation is discussed. All calculations have been carried out by using the Monte Carlo algorithm.

Journal Article↗

Order-parameter-based Monte Carlo simulation of crystallization.

A Monte Carlo simulation method is presented for simulation of phase transitions, with emphasis on the study of crystallization. The method relies on a random walk in order parameter Phi(q(N)) space to calculate a free energy profile between the two coexisting phases. The energy and volume data generated over the course of the simulation are subsequently reweighed to identify the precise conditions for phase coexistence. The usefulness of the method is demonstrated in the context of crystallization of a purely repulsive Lennard-Jones system. A systematic analysis of precritical and critical nuclei as a function of supercooling reveals a gradual change from a bcc to a fcc structure inside the crystalline nucleus as it grows at large degrees of supercooling. The method is generally applicable and is expected to find applications in systems for which two or more coexisting phases can be distinguished through one or more order parameters.

Journal Article↗

Correlated wave functions for the ground and some excited states of the iron atom.

We study the states arising from the [Ar]4s(2)3d6 and [Ar]4s(1)3d7 configurations of iron atom with explicitly correlated wave functions. The variational wave function is the product of the Jastrow correlation factor times a model function obtained within the parametrized optimized effective potential framework. A systematic analysis of the dependence of both the effective potential and the correlation factor on the configuration and on the term is carried out. The ground state of both, the cation, Fe+, and anion, Fe-, are calculated with correlated wave functions and the ionization potential and the electron affinity are obtained.

Journal Article↗