Alcohol use disorder as a risk factor for violent offending in a sample of female forensic-psychiatric inpatients

Introduction

Female gender is associated with a lower risk for aggressive behaviour and violent offending. Well established risk factors for aggressive behaviour are alcohol and other substance use, but previous studies focused mainly on male offenders and the general population. However, for therapeutic and prognostic reasons it is important to understand pathways to female offending.

Objectives

To examine a sample of female forensic-psychiatric inpatients regarding the association of alcohol (AUD) and other substance use disorders (SUD) with violent offending (homicide, assault, robbery).

Methods

We conducted a retrospective cohort study of 334 female patients discharged before 01.01.2019 from a secure psychiatric hospital in Germany.

Results

In total, 72% of the patients with AUD committed a violent crime, leading to admission to secure psychiatric treatment. In comparison a statistically significant lower rate (19%) of the SUD group was convicted of violent offending. Over 70% of the participants with AUD had a family history of AUD, and over 83% experienced physical violence in adulthood. We found no group differences (AUD vs. SUD) regarding aggressive behaviour during inpatient treatment.

Conclusions

According to our results, AUD compared to other SUD, is a significant risk factor for violent offending in women. A family background with AUD and a history of physical abuse might function as a risk factor for both: developing an AUD and violent offending. The comparable rates of aggression in both groups during inpatient treatment suggest that abstinence is a protective factor.

Disclosure

No significant relationships.

Pad in forensic psychiatry

Introduction

A recent court decision in Germany defined assisted suicide as a basic human right. Consequently, the discussion regarding PAD needs to be extended to people who are in forensic/secure psychiatric hospitals or prisons, sometimes without any prospects of release. Several studies have shown that long-term hospitalization and detention are associated with feelings of hopelessness, depression and suicidal ideations. Moreover, the resources for adequate therapy are often rare. This results in complex moral challenges for mental health care.

Objectives

To review current practices in countries that allow PAD and to discuss ethical conflicts.

Methods

Literature review; international comparison of current regulations.

Results

A majority of the literature on PAD in detention refers to prisoners with terminal medical conditions. Single case reports of PAD-requests of mentally disordered offenders aroused great public interest. The resulting ethical conflicts are similar to those issues regarding PAD and mental disorder in general. However, in secure treatment settings and detention additional aspects such as adverse living conditions and inadequate access to mental health care need to be taken into account.

Conclusions

If unbearable pain is not a precondition for assisted suicide, then mentally disordered and healthy offenders have a right to request PAD, provided they have medical decision-making capacity. Considering the common insufficient mental health care for people in detention, policy and law makers need to ensure that access to PAD will not replace therapy. Professionals involved in PAD evaluations need support by specific guidelines.

Disclosure

No significant relationships.

Cardiopulmonary resuscitation (CPR)-related posterior rib fractures in neonates and infants following recommended changes in CPR techniques

Posterior rib fractures are highly indicative of non-accidental trauma (NAT) in infants. Since 2000, the "two-thumbs" technique for cardiopulmonary resuscitation (CPR) of newborns and infants has been recommended by the American Heart Association (AHA). This technique is similar to the grip on an infant's thorax while shaking. Is it possible that posterior rib fractures in newborns and infants could be caused by the "two-thumbs" technique? Using computerized databases from three German children's hospitals, we identified all infants less than 12 months old who underwent professional CPR within a 10-year period. We included all infants with anterior-posterior chest radiographs taken after CPR. Exclusion criteria were sternotomy, osteopenia, various other bone diseases and NAT. The radiographs were independently reviewed by the Chief of Pediatric Radiology (MB) and a Senior Pediatrician, Head of the local Child Protection Team (IF). Eighty infants with 546 chest radiographs were identified, and 50 of those infants underwent CPR immediately after birth. Data concerning the length of CPR was available for 41 infants. The mean length of CPR was 11min (range: 1-180min, median: 3min). On average, there were seven radiographs per infant. A total of 39 infants had a follow-up radiograph after at least 10 days. No rib fracture was visible on any chest X-ray. The results of this study suggest rib fracture after the use of the "two-thumbs" CPR technique is uncommon. Thus, there should be careful consideration of abuse when these fractures are identified, regardless of whether CPR was performed and what technique used. The discovery of rib fractures in an infant who has undergone CPR without underlying bone disease or major trauma warrants a full child protection investigation.

Child abuse - some aspects for neurosurgeons

Neurosurgeons are mainly concerned with child abuse in cases of severe cranio-cerebral trauma. Aim of the present paper is to highlight the clinical picture and symptoms in cases of child abuse and our multidisciplinary approach to reveal a solid diagnosis. The detection of child abuse requires a high index of suspicion, especially in cases of subtle injuries. Besides reporting to the appropriate agencies primary goals are to terminate suspected abuse and to prevent further harm to the child. All this requires a confirmed diagnosis.

[Dose area product of pediatric VCUG with regard to the strongly lowered German diagnostic reference levels]

PURPOSE

To compare the dose area products of pediatric VCUG in daily practice with the dramatically reduced official German diagnostic reference levels, which are based on selected data.

MATERIALS AND METHODS

413 consecutive pediatric VCUG examinations were analyzed.

RESULTS

The mean dose area product of all examinations was 0.97 dGycm². This is below the lowest reference level that is valid for neonates. In 12 cases (5.6 %) the achieved dose area product was higher than the corresponding reference level.

CONCLUSION

Using the available techniques for radiation protection, it is possible in the daily routine to meet the official diagnostic reference levels for children, which have been reduced by up to 80 %, even though these levels are based on a selected, possibly non-representative data set.

Progressive lipo-lymphedema associated with increased activity of dermal fibroblasts in monoclonal gammopathy of undetermined significance: is there a causal relationship?

The pathophysiology of skin diseases associated with monoclonal gammopathies is generally unknown. Our aim was to investigate whether a monoclonal gammopathy could be a causal factor in progressive lymphedema. We describe a 75 year old patient with a rapidly progressive lipo-lymphedema and a monoclonal gammopathy of unknown significance (MGUS) suspected as a key etiological factor. Dermal fibroblasts were cultured from lesional lower leg skin and non-lesional abdominal skin and compared to healthy control fibroblasts. We found 10-fold elevated basic fibroblast growth factor 2 (FGF-2) in the patient's serum and significantly increased basal FGF-2 production of lesional and non-lesional fibroblasts compared to healthy controls. Upon restimulation with patient or healthy control serum, lesional fibroblasts showed significantly increased proliferation rates and FGF-2 production in vitro. Non-lesional abdominal fibroblasts showed an intermediate phenotype between lesional and control fibroblasts. Our findings provide the first evidence that lesional dermal fibroblasts from lipo-lymphedema with plasma cell infiltration show increased proliferation and FGF-2 production and that both local tissue factors and altered FGF-2 serum levels associated with monoclonal gammopathies might contribute to this phenotype. Thus we propose a possible pathophysiologic link between the gammopathy-associated factors and the generation of lymphedema with initial fibrogenesis aggravating pre-existing lipedema.

Measurement of magnetic susceptibility in pulsed magnetic fields using a proximity detector oscillator

We present a novel susceptometer with a particularly small spatial footprint and no moving parts. The susceptometer is suitable for use in systems with limited space where magnetic measurements may not have been previously possible, such as in pressure cells and rotators, as well as in extremely high pulsed fields. The susceptometer is based on the proximity detector oscillator, which has a broad dynamic resonant frequency range and has so far been used predominantly for transport measurements. We show that for insulating samples, the resonance frequency behavior as a function of field consists of a magnetoresistive and an inductive component, originating, respectively, from the sensor coil and the sample. The response of the coil is modeled, and upon subtraction of the magnetoresistive component the dynamic magnetic susceptibility and magnetization can be extracted. We successfully measure the magnetization of the organic molecular magnets Cu(H(2)O)(5)(VOF(4))(H(2)O) and [Cu(HF(2))(pyz)(2)]BF(4) in pulsed magnetic fields and by comparing the results to that from a traditional extraction susceptometer confirm that the new system can be used to measure and observe magnetic susceptibilities and phase transitions.

[Sonographic volumetry of the urinary bladder in paediatric patients. value of different calculation formulae taking into account a simple formula that is calculable in one's head]

BACKGROUND

Volumetry of the urinary bladder is a frequently performed sonographic procedure. Usually the formula of the prolate ellipsoid is applied for this purpose. In the literature however a variety of different formulas is proposed.

PURPOSE

The aim of this study was to evaluate different simple formulae used for the calculation of the bladder volume in children, taking into account a formula that is easily calculable in one's head.

MATERIAL AND METHODS

139 children were examined by sonography, 6 different formulae were applied. The bladder volume was confirmed by micturition. Only children without residual volume were included in the study.

RESULTS

82 children (mean age: 8.5 years) could be included with a mean bladder volume of 92 mL (0 to 227 mL). The mean error ranged from 20.2 % (cuboid formula) to 38.0 % (prolate ellipsoid). With decreasing bladder volume all formulae showed an increasing error and a tendency for underestimation of the bladder volume. For small volumes best results were achieved by the cuboid formula with a mean error of 26.4 %. The formula of the prolate ellipsoid yielded the worst results. The proposed truncation formula, easily calculable in one's head, showed better results than both the formula of the prolate ellipsoid and the cuboid formula.

CONCLUSION

The formula of the prolate ellipsoid should not be used for bladder volumetry in children. Small bladder volumes should be calculated by multiplying the three diameters of the bladder (cuboid formula). If the calculated volume lies above 60 mL a correction factor of 0.8 should be used to avoid overestimation of the true bladder volume.

[Sonographic bladder volumetry in children: comparison of conventional B-mode sonography and automatic volumetry with a handheld scanning device without imaging]

PURPOSE

Evaluation of a handheld sonographic tool for the automatic estimation of bladder volume in comparison with conventional sonography in children under clinical conditions.

MATERIALS AND METHODS

139 children (age: 30 days - 17 years) were examined with both conventional sonography and the handheld scanning device BVI 6200. For conventional sonography two different formulas were used to calculate the bladder volume.

RESULTS

The mean error of the three methods was 22.4 % for the handheld tool, 37.4 % for the most frequently used prolate ellipsoid formula in conventional sonography, and 23 % for an alternative formula recommended in the literature. In 19 cases the first automated sonography scan showed a false-negative result (empty bladder), while the automatically calculated volumes were between 17 and 60 ml in 5 cases of empty bladder. In one of these cases a megaureter and in another an ovarian cyst were detected by conventional ultrasound.

CONCLUSION

Since pathologies are not visualized and can be misinterpreted as a nonempty bladder, the automated method should only be used in follow-up studies. In every case automated volumetry should be performed repeatedly to avoid false-negative results.

[Livid polycyclic plaques of the lower extremities]

In 10%-55% of patients, leukemia cutis (LC) manifest as a symptom of acute myelomonocytic leukemia and is associated with a poor overall prognosis. Disseminated bluish-violet or red-brownish papules and plaques, nodules and also hemorrhagic ulcers may dominate the initial clinical picture. Importantly, nonspecific infiltrates (leukemids) must be differentiated from specific infiltrates of malignant cells in patients presenting with dermatoses and concomitant underlying hematopoietic neoplasms. The role of the dermatologist is the rapid clinical and dermatohistopathological diagnosis in order to allow immediate, adequate treatment of the patient's underlying systemic disease.

Cutis verticis gyrata secondary to acne scleroticans capitis

We report the case of a 35-year-old patient with secondary cutis verticis gyrata (CVG) that histologically presented as acne scleroticans capitis. Clinically, the diagnosis of acne conglobata was made. The CVG developed under systemic corticosteroid treatment of an ulcerative colitis. Corticosteroids were discontinued and a therapeutic attempt was made with isotretinoin. Although under this treatment the conglobate acne healed, the CVG remained unaltered. Dermatosurgical intervention by a scalp reduction plasty finally resulted in a marked improvement of symptoms and acceptable cosmetic outcome.

Complete remission of a primary cutaneous B-cell lymphoma of the lower leg by first-line monotherapy with the CD20-antibody rituximab

BACKGROUND

Rituximab is a genetically engineered antibody recognizing the CD20 antigen known to be expressed by more than 95% of B-cell lymphomas. Recently the antibody has been approved for routine administration in primary extracutaneous, treatment-refractory or relapsed low-grade, follicular non-Hodgkin B-cell lymphomas. With regard to the pathogenetically related primary cutaneous lymphomas, the so-called large B-cell lymphoma of the leg represents a distinct, but rare subentity. In an 89-year-old, multimorbid patient who was affected by such a non-resectable CD20+ large B-cell lymphoma limited to the skin of both lower legs, rituximab was used as a first-line monotherapy in order to avoid local or systemic toxicities inevitably linked to conventional treatment modalities, i.e., radio- or chemotherapy.

METHODS

Rituximab was administered at a dosage of 375 mg/m(2) i.v. eight times in weekly intervals. As a premedication we used prednisolone 150 mg i.v. as well as loratadine 10 mg p.o. 1 h before each rituximab infusion.

RESULTS

The treatment was well tolerated without any adverse reactions, but was accompanied by a mild transient blood eosinophilia. The histologically proven, exophytic, multi-nodular lymphoma showed a substantial regression already at 2 weeks after the onset of the rituximab treatment. At 8 weeks we observed a complete clinical remission which is now stabile for a follow-up period of 6 months without any maintenance therapy.

CONCLUSIONS

Our case observation demonstrates that an intensified, i.e. eightfold, rituximab application in weekly intervals may be a highly effective, tumor target cell-specific first-line monotherapy in the management of primary cutaneous large B-cell lymphoma of the leg. Given the rareness of the disease, the result as well as the possible contribution of the prednisolone premedication will have to be evaluated in a future, controlled, multi-centre study.

Shelf life extension of pre-baked buns by an ACTIVE PACKAGING ethanol emitter

The paper reports the influence of an ethanol emitter (Ethicap) on the microbiological condition and the shelf life extension of a bakery product. Pre-baked buns, with a water activity of 0.95, were packaged with different amounts of Ethicap and stored at room temperature. Yeasts and moulds remained largely absent from the core of the pre-baked bun (< 10(2) cfu g(-1)) during storage, independent of the presence of ethanol. The total mesophilic count was low at the beginning of the storage experiment (< 10(2) cfu g(-1)), but increased without ethanol within 1 week to an unacceptable level. In the presence of ethanol, the total mesophilic count stabilizes at a consumable level of 10(5)-10(6) cfu g(-1). The increase of total mesophilic count was caused by growth of a Bacillus spp., probably B. subtilis. Mould growth on the outer surface is limiting for shelf life extension. On the pre-baked buns, the following moulds were present: Penicillium solitum, P. commune, P. corylophilum, Cladosporium sphaerospermum and C. herbarum. These started to grow within 4-6 days. Mould growth can be delayed for 13 days by adding Ethicap. The ethanol probably has to be absorbed by the pre-baked bun to be effective in growth suppression of the Bacillus spp. the moulds. The pre-baked buns absorb most of the ethanol from the package headspace, and the ethanol content of the products is approximately 0.8 weight% after 21 days. This largely exceeds the overall migration limit of 60 mg kg(-1) food (0.006 weight%).

[Successful symptomatic tazarotene treatment of juvenile acanthosis nigricans of the familial obesity-associated type in insulin resistance]

An 11-year-old boy suffering from morbid obesity since infancy developed at age 9 a progressive brown-black hyperpigmentated and hyperkeratotic eruption in the neck and axillary region with minor involvement of both groins. Based on this clinical picture, and confirmed by histopathology, we diagnosed acanthosis nigricans. Following a thorough endocrinological examination and because the patient's obese mother showed similar skin lesions, the disease was subclassified as a familial obesity-associated type of acanthosis nigricans associated with insulin resistance. In a right-left-comparison the affected skin of one body side was treated with tazarotene 0.05% versus urea 10%, once daily each. A great benefit for the tazarotene-treated over the opposite side could already be seen after three weeks which was also verified by dermatohistopathology. Three months after topical tazarotene treatment had been extended to both sides, the residual lesions were significantly improved. The highly satisfying, good result has been maintained up to now by a continuous topical retinoid treatment over 18 months, usually with an interval application regimen, i.e., 3 x per week.

Immobilization of sugar-non-specific nucleases by utilizing the streptavidin--biotin interaction

Due to their high enzymatic activity, the sugar-non-specific endonucleases from Serratia marcescens and Anabaena can be used for a number of applications, such as the removal of contaminating genetic material from biological preparations, footprinting studies, and the determination of nucleic acids in biochemical samples. These methods would benefit from immobilized nucleases. For this purpose, a single cysteine residue was added at the N-terminus of the Serratia and Anabaena nucleases and subsequently modified with a maleimide-biotin conjugate. Alternatively, a biotin acceptor domain was fused to the Anabaena nuclease, allowing biotinylation during expression in E. coli without a further chemical step. The attachment of biotin-modified nucleases to streptavidin-coated paramagnetic beads and to streptavidin-coated surface plasmon resonance sensor chips (to study interactions with substrate and inhibitor) worked well when aggregates present in the protein preparations were removed by ultrafiltration. These methods should be of general use for similar enzyme systems.

Ectodomain shedding, translocation and synthesis of SorLA are stimulated by its ligand head activator

The single transmembrane receptor SorLA is the mammalian orthologue of the head activator-binding protein, HAB, from hydra. The human neuronal precursor cell line NT2 and the neuroendocrine cell line BON produce head activator (HA) and respond to HA by entry into mitosis and cell proliferation. They express SorLA, and bind HA with nanomolar affinity. HA coupled to Sepharose is able to precipitate SorLA specifically proving that SorLA binds HA. Using antisera directed against extra- and intracellular epitopes we find SorLA as membrane receptor and as soluble protein released from cells into the culture medium. Cell lines differ strongly in processing of SorLA, with NT2 cells expressing SorLA mainly as membrane receptor, whereas release predominates in BON cells. Soluble SorLA lacks the intracellular domain and is shed from the transmembrane protein by a metalloprotease. Release from cells and brain slices is stimulated by HA and by phorbol ester, and it is blocked by a metalloprotease inhibitor and by lowering the temperature to 20 degrees C. Blockade of SorLA shedding and treatment of cells with SorLA antisense oligonucleotides lead to a decrease in the rate of cell proliferation. From this we conclude that SorLA is necessary to mediate the mitogenic effect of endogenous HA. HA enhances the translocation of SorLA from internal membranes to the cell surface and its internalization. In addition, HA stimulates SorLA synthesis hinting at an autocatalytic feedback loop in which the ligand activates production, processing, and translocation of its receptor.

Successful treatment of angiosarcoma of the scalp by intralesional cytokine therapy and surface irradiation

An 88-year-old woman presented to us with angiosarcoma of the scalp that had developed over a 6-month period following previous trauma. Despite explicit information concerning the extremely malignant potential of the tumour the patient refused any surgical intervention. However, she agreed to receive local, intralesional interferon alpha-2b and interleukin-2 therapy. After partial remission of the tumour, the intralesional cytokine injections were combined with surface radiotherapy. This combination therapy led to a 2-year remission of both the tumour and sonographically suspicious cervical lymph nodes. Apart from the typical, moderate side-effects of interferon alpha-2b and interleukin-2 the therapy was well tolerated. In conclusion, in our limited experience intralesional cytokine therapy--alone as well as in combination with surface irradiation--seems to be an alternative therapeutic option for patients who is not a candidate for surgery.

A head-activator binding protein is present in hydra in a soluble and a membrane-anchored form

The neuropeptide head activator plays an important role for proliferation and determination of stem cells in hydra. By affinity chromatography a 200 kDa head-activator binding protein, HAB, was isolated from the multiheaded mutant of Chlorohydra viridissima. Partial amino acid sequences were used to clone the HAB cDNA which coded for a receptor with a unique alignment of extracellular modules, a transmembrane domain, and a short carboxy-terminal cytoplasmic tail. A mammalian HAB homologue with identical alignment of these modules is expressed early in brain development. Specific antibodies revealed the presence of HAB in hydra as a transmembrane receptor, but also as secreted protein, both capable of binding head activator. Secretion of HAB during regeneration and expression in regions of high determination potential hint at a role for HAB in regulating the concentration and range of action of head activator.

Demonstration of HPV 24 in long-standing Heck's disease with malignant transformation

We report on the rare case of a 64-year-old European woman with a viral acanthoma of the oral mucosa of the clinical Heck type with unprecedented molecular-biological proof of HPV 24 DNA and so far undescribed malignant transformation with a long existence of the vegetation. After surgical therapy a circumscribed relapse of viral acanthoma developed, which responded favourably to a combined antiviral and antiproliferative therapy with acitretin perorally and interferon, first subcutaneously, later intralesionally for 3 months.

Cleavage experiments with deoxythymidine 3',5'-bis-(p-nitrophenyl phosphate) suggest that the homing endonuclease I-PpoI follows the same mechanism of phosphodiester bond hydrolysis as the non-specific Serratia nuclease

We show here that two nucleases, Serratia nuclease and I-PpoI, with contrasting specificities, i.e. non-specific vs. highly sequence specific, share a structurally similar active site region with conservation of the catalytically relevant histidine and asparagine residues. On the basis of a comparison of the available structures and biochemical data for wild type and mutant variants of Serratia nuclease and I-PpoI we propose that both enzymes have a common catalytic mechanism, a proposition that is supported by our finding that both enzymes accept deoxythymidine 3',5'-bis-(p-nitrophenyl phosphate) as a substrate and cleave it in an identical manner. According to this mechanism a histidine residue functions as a general base and Mg2+ bound to an asparagine residue as a Lewis acid in phosphodiester bond cleavage.

On the advantage of being a dimer, a case study using the dimeric Serratia nuclease and the monomeric nuclease from Anabaena sp. strain PCC 7120

The extracellular endonucleases from Serratia marcescens and Anabaena sp. are members of a family of nonspecific endonucleases. In contrast to the monomeric Anabaena nuclease, the Serratia nuclease is a dimer of two identical subunits. To find out whether the two active sites of the Serratia nuclease function independently of each other and what the advantage of being a dimer for this enzyme might be, we produced (i) dimers in which the two subunits were cross-linked, (ii) heterodimers consisting of a wild type and an inactive mutant subunit which were also cross-linked, and (iii) monomeric variants which are unable to dimerize. The monomeric H184R variant and the cross-linked S140C variant exhibit the same activity as the wild type enzyme, while the cross-linked heterodimer with one inactive subunit shows only half of the activity of the wild type enzyme, demonstrating functional independence of the two subunits of the Serratia nuclease. On the other hand at low enzyme and substrate concentrations dimeric forms of the Serratia nuclease are relatively more active than monomeric forms or the monomeric Anabaena nuclease in cleaving polynucleotides, not, however, oligonucleotides, which is correlated with the ability of dimeric forms of the Serratia nuclease to form large enzyme-substrate networks with high molecular weight DNA and to cleave polynucleotides in a processive manner. We conclude that in the natural habitat of Serratia marcescens where the supply of nutrients may become growth limiting the dimeric nuclease can fulfil its nutritive function more efficiently than a monomeric enzyme.

Synthesis and biochemical characterization of obligatory dimers of the sugar non-specific nuclease from Serratia marcescens using specifically designed bismaleimidoalkanes as SH-specific crosslinking reagents

The genetically engineered S140C variant of the homodimeric nuclease from Serratia marcescens was crosslinked across the dimer interface at the Cys 140 residues using bifunctional SH-specific 1,1'-alkanediyl-bis-pyrrole-2,5-diones of different lengths. These bismaleimidoalkanes were synthesized by the condensation of n-alkyldiamines with maleic anhydride and subsequent cyclization with acetic anhydride and sodium acetate. Bismaleimidohexane (BMH) which gave the best crosslinking yield was used to produce in preparative amounts crosslinked Serratia nuclease. The crosslinked protein has the same secondary structure and exhibits the same guanidinium chloride unfolding behavior as the wild type enzyme or the non-covalently linked S 140C variant. In contrast, in thermal unfolding experiments the crosslinked dimer behaves differently from the wild type enzyme or the non-covalently linked S140C variant. CD-spectra recorded during temperature rise showed only minor changes of the secondary structure composition for the wild type enzyme and the non-covalently linked S140C variant, whereas in the case of the crosslinked S140C dimer a distinct increase of the CD effect was observed corresponding to an increase in alpha-helix. Our results demonstrate that bismaleimidoalkanes are very well suited to covalently link subunits of proteins, provided suitably located cysteine residues are present.

Crosslinking the EcoRV restriction endonuclease across the DNA-binding site reveals transient intermediates and conformational changes of the enzyme during DNA binding and catalytic turnover

EcoRV completely encircles bound DNA with two loops, forming the entry and exit gate for the DNA substrate. These loops were crosslinked generating CL-EcoRV which binds and releases linear DNA only slowly, because threading linear DNA into and out of the DNA-binding 'tunnel' of CL-EcoRV is not very effective. If the crosslinking reaction is carried out with a circular bound DNA, CL-EcoRV is hyperactive towards the trapped substrate which is cleaved very quickly but not very accurately. CL-EcoRV also binds to, but does not cleave, circular DNA when added from the outside, because it cannot enter the active site. Based on these results a two-step binding model is proposed for EcoRV: initial DNA binding occurs at the outer side of the loops before the gate opens and then the DNA is transferred to the catalytic center.

Genetic engineering, production and characterisation of monomeric variants of the dimeric Serratia marcescens endonuclease

The Serratia nuclease is a non-specific endonuclease which cleaves single- and double-stranded RNA and DNA. It is a member of a large family of related endonucleases, most of which are dimers of identical subunits, with the notable exception of the Anabaena nuclease which is a monomer. In order to find out whether the dimer state of the Serratia nuclease is essential for its function we have produced variants of this nuclease which based on the crystal structure (Miller, M.D. and Krause, K.L. (1996), Protein Science 5, 24-33) were expected to be unable to dimerise. We demonstrate here that these variants, H184A, H184N, H184T and H184R, are monomers and have the same secondary structure, stability towards chemical denaturation and activity as the wild-type enzyme. This allows to conclude that the dimeric state is not essential for the catalytic function of the Serratia nuclease. In contrast, the S179C variant which is also a monomer shows little activity, presumably because this amino acid substitution changes the structure of the enzyme.

Biochemical characterization of Anabaena sp. strain PCC 7120 non-specific nuclease NucA and its inhibitor NuiA

We have established overexpression systems and purification protocols for NucA and NuiA, a sugar non-specific nuclease and its protein inhibitor from Anabaena sp. strain PCC 7120, in order to characterize these proteins in detail. CD spectroscopy revealed that NucA has a similar secondary-structure composition, 13% alpha helix and 20% beta sheet, to the related Serratia nuclease, while NuiA represents a protein with a higher alpha-helical (29%) and beta-sheet (24%) content than NucA. Denaturation experiments showed that the stabilities of NucA and NuiA are in the typical range for proteins of mesophilic organisms, NuiA with deltaG0H2O = 63.4 J x mol(-1)residue, being slightly more stable than its target NucA with delta deltaG0H2O = 46.3 J x mol(-1)residue. The nuclease requires divalent metal ions as cofactors, the optimum concentration being around 5 mM for Mn2+ or Mg2+. The order of effectiveness of various divalent cations to function as cofactors for the hydrolytic activity of NucA is Mn2+ = Co2+ > Mg2+ > or = Ni2+ >> or Ca2+ = Cd2+ at a concentration of 5 mM. Nuclease activity decreases with increasing concentration of monovalent salt. The activity of NucA shows a pH optimum at pH 5.5-7.5. The temperature optimum is around 35 degrees C, the activation energy was calculated to be 53 kJ mol(-1). The specific activity of the nuclease towards high molecular-mass DNA is 8.4 x 10(6) Kunitz-units x mg(-1), which means that NucA is one of the most active nucleases known. Kinetic constants for the cleavage of various DNA and RNA substrates by NucA are all in the range Km < or = 0.1 mg x ml(-1) and k(cat) approximately 1000 s(-1). As other non-specific nucleases, NucA exhibits sequence preferences, similar to the related Serratia nuclease, NucA avoids cleavage of d(A) x d(T) tracts. The nucleolytic activity of NucA is completely inhibited at equimolar concentrations of nuclease and inhibitor. An ultracentrifugation analysis showed that NucA and NuiA form a 1:1 complex. The interaction of NucA with NuiA was also investigated by CD spectroscopy and revealed no major conformational changes upon complex formation of the two proteins.

[Allopurinol as an inducer of acute graft-versus-host-like drug reaction. Case report with review of the literature]

Although drug eruptions resembling graft-versus-host disease are rare, GvH-like reactions to the sulfhydryl group of drugs (penicillamine, captopril, gold sodium), phenobarbital and hepatitis vaccine have been described. Clinical reports concerning acute GvH-like drug rash are very uncommon and restricted to acetylsalicylic acid and spironolactone. We report on a patient who developed an acute GvH-like drug reaction caused by allopurinol. To our knowledge this variant of cytotoxic drug eruption has not yet been reported in literature.

[Multiple sleep latency test in patients with obstructive snoring]

The objective of our study was to examine the effect of the n-CPAP on day tiredness of patients suffering from obstructive snoring. This effect was objectified by means of the Multiple Sleep Latency Test (MSLT). The MSLT was performed with optimal pressure at 8.00, 10.00, 12.00 and 14.00 hrs. subsequent to the control night and the third CPAP night. The latencies of falling asleep and the sleep stages were determined in accordance with the criteria of Rechtschaffen and Kales. The average latency of falling asleep before therapy was: at 8.00 hrs 9.0 +/- 14.2 min, at 14.00 hrs. 7.2 +/- 6.3 min. The following latencies of falling asleep were observed after the third CPAP night: 8.00 hrs. 14.2 +/- 6.3, 10.00 hrs. 13.4 +/- 6.4, 12.00 hrs. 13.7 +/- 6.4 hrs. 13.7 +/- 6.0 min. This means that after the therapy there was a marked tendency to longer latencies at all 4 points of measurement with significant differences at 12.00 and 14.00 hrs. A comparison of the quality of sleep before and after the therapy yielded an increase in deep sleep and a significant increase in REM density during dream sleep. MSLT enabled objectivation of improved sleep quality and of subjective decrease in day tiredness after CPAP therapy in patients with obstructive snoring. The latency in falling asleep increased at all the points of measurement. Nevertheless, interindividual differences are great, compared with the uniform subjective success of CPAP therapy achieved with these patients.

Purification of a head-activator receptor from hydra

Head activator (HA) is a neuropeptide conserved from hydra to humans. It acts in the development of neuronal cells and is, in hydra, an important factor in head regeneration. Here we report the solubilization and purification of one head activator receptor (Kd approximately 1 nM) from a multiheaded mutant of Chlorohydra viridissima using HA affinity chromatography. Functional solubilization of the HA receptor from hydra membranes was best performed with Triton X-100 or Chaps. The addition of salt or urea and the protein concentration were important parameters in determining the yield of solubilized receptor. For affinity chromatography HA was coupled to Sepharose. The length of the spacer was optimized with respect to binding of the solubilized HA receptor. After rigorous washing a 200-kDa protein was eluted from HA Sepharose but not from control Sepharoses coupled to bradykinin or without peptide. Ligand binding was preserved in the eluate from the HA Sepharose, and a 200-kDa protein could be photoaffinity labeled. The 200-kDa protein was shown to be glycosylated mainly of the N-linked type. By Edman degradation of the purified protein sequence information was obtained for the N-terminus and after protease digestion for several internal peptides.

Analysis of the reaction mechanism of the non-specific endonuclease of Serratia marcescens using an artificial minimal substrate

We have studied the mechanism of action of the Serratia nuclease using deoxythymidine 3',5'-bis-(p-nitrophenyl-phosphate) as a substrate. A comparison of the activity with which the wild-type enzyme and several mutant enzymes attack this artificial substrate and herring sperm DNA, respectively, supports the suggestion that His89 is the general base and a Mg2+ ion bound to Glu127 the general acid in the mechanism of phosphodiester bond hydrolysis by the Serratia nuclease, and that Asn119 directly participates in catalysis, for example by transition state stabilisation. Arg57, Arg87 and Arg131, essential for nuclease activity, are not needed for cleavage of the artificial substrate, suggesting that they are involved in binding and positioning of nucleic acid substrates.

[Topical therapy of extramammary Paget's disease]

A case of locally extensive perigenital Paget's disease in an 84-year-old man is presented. Topical application of 5-fluorouracil emerged as the safest and most effective treatment because of the patient's poor general condition and the extensive involvement of the pubic and genital skin.