Cloning and expression of a novel human glutaredoxin (Grx2) with mitochondrial and nuclear isoforms

Glutaredoxin (Grx) is a glutathione-dependent hydrogen donor for ribonucleotide reductase. Today glutaredoxins are known as a multifunctional family of GSH-disulfide-oxidoreductases belonging to the thioredoxin fold superfamily. In contrast to Escherichia coli and yeast, a single human glutaredoxin is known. We have identified and cloned a novel 18-kDa human dithiol glutaredoxin, named glutaredoxin-2 (Grx2), which is 34% identical to the previously known cytosolic 12-kDa human Grx1. The human Grx2 sequence contains three characteristic regions of the glutaredoxin family: the dithiol/disulfide active site, CSYC, the GSH binding site, and a hydrophobic surface area. The human Grx2 gene, located at chromosome 1q31.2--31.3, consisted of five exons that were transcribed to a 0.9-kilobase human Grx2 mRNA ubiquitously expressed in several tissues. Two alternatively spliced Grx2 mRNA isoforms that differed in their 5' region were identified. These corresponded to alternative proteins with a common 125-residue C-terminal Grx domain but with different N-terminal extensions of 39 and 40 residues, respectively. The 125-residue Grx domain and the two full-length variants were expressed in E. coli and exhibited GSH-dependent hydroxyethyl disulfide and dehydroascorbate reducing activities. Western blot analysis of subcellular fractions from Jurkat cells with a specific anti-Grx2 antibody showed that human Grx2 was predominantly located in the nucleus but also present in the mitochondria. We further showed that one of the mRNA isoforms corresponding to Grx2a encoded a functional N-terminal mitochondrial translocation signal.

In vitro effect of amikacin, imipenem, cefodizime, IFNalpha-2a alone and combinations of antibiotics with IFNalpha-2a on polymorphonuclear leukocyte function in chronic hepatitis patients

The in vitro effect of amikacin (8 microg/ml), imipenem (30 microg/ml), cefodizime (10 microg/ml), interferon alpha-2a (IFNalpha-2a) (10 IU/ml) and antibiotic combinations with IFNalpha-2a on polymorphonuclear leukocyte (PMN) functions (phagocytosis and intracellular killing of Candida albicans blastospores) was investigated in chronic hepatitis B patients. Phagocytosis and candidacidal activity was not affected after pretreatment of PMNs with amikacin and imipenem (p > 0.05). Phagocytic activity was enhanced after pretreatment of PMNs with cefodizime and IFNalpha-2a compared with that of control PMNs (p < 0.05), but candidacidal activity was not affected by the same drugs (p > 0.05). Phagocytic and intracellular activity of PMNs were not affected by combinations of IFNalpha-2a and antibiotics (p > 0.05).

The role of different protein components from the Haemophilus ducreyi cytolethal distending toxin in the generation of cell toxicity

Cytolethal distending toxin of Haemophilus ducreyi (HdCDT) is a multicomponent toxin, encoded by an operon consisting of three genes, cdtABC. To investigate the role of the individual products in generation of toxicity, recombinant plasmids were constructed allowing expression of each of the genes individually or in different combinations in Escherichia coli and Vibrio cholerae. Expression of all three genes (cdtABC) was necessary to generate toxicity on cells, and no activity was obtained using combinations in which only one or two of the genes were expressed. Of the individual gene products, the CdtA was shown to exist in two forms with an MW of 23 and 17 kDa, respectively. The CdtB protein alone resulted in DNase activity. CdtC purified from both toxic and non-toxic extracts (from strains expressing cdtCAB and cdtC, respectively) had a molecular weight of about 20 kDa and reacted with a CdtC-specific monoclonal antibody. However, the protein isoelectric point (pI) of CdtC from toxic preparations was about 1.5 pH units more basic than from non-toxic ones. Both forms were immunogenic giving rise to toxin-neutralizing antibodies. Toxicity was reconstructed by combining non-toxic cell sonicates from E. coli, expressing CdtA, CdtB and CdtC proteins individually. Only combinations including all three products gave toxicity, indicating that all are actively involved in the generation of toxic activity on cells. The reconstruction resulted in a 1.5 pH unit shift in the PI of CdtC, making it identical to that of the protein isolated from bacteria expressing cdtABC. The results showed that the CdtB component produces DNase activity, but cell toxicity depends on the involvement of the other two components of CDT and is associated with absorption of all three proteins by HEp-2 cells.

Vertebral deformation in urban Swedish men and women: prevalence based on 797 subjects

Vertebral fracture-deformation, a common feature of osteoporosis, shows considerable age, sex and geographical variation. We present the prevalence in an urban population of south-west Sweden. Lateral spine radiographs of 797 men and women, age 50-86 years, were evaluated by morphomety. The age-standardized prevalence of subjects with vertebral deformation using the deformation criterion -3 SD was 39 (95%CI 34-43)% in women and 33 (95%CI 28-38)% in men. The prevalence increased with age in both sexes. After adjustment for age, women had a higher prevalence than men, odds ratio 1.4. The proportion of vertebrae with deformation ranged from 2%-11%, increasing with age. The vertebrae most commonly deformed were Th 11, Th 12 and L1.

Seasonal affective disorder and serotonin-related polymorphisms

Disturbances in central serotonergic systems have been hypothesized to be involved in seasonal affective disorder (SAD). Association between SAD and the shorter allele of the serotonin transporter promoter repeat length polymorphism (5-HTTLPR) has been reported in an American sample. We have genotyped 82 SAD patients and 82 healthy controls from Sweden, Finland, and Germany for this and five other polymorphisms in the genes coding for serotonin receptors 5-HT2A and 5-HT2C, tryptophan hydroxylase and white. No associations with SAD or seasonality (seasonal variations in mood and behavior) were detected. Although minor effects cannot be excluded, our results suggest that these polymorphisms do not play a major role in the pathogenesis of SAD in the northern European population.

Undergraduate medical education: tendencies and requirements in a rapidly developing Europe

This study pinpoints the necessity to constantly monitor local approaches in undergraduate medical education on an inter-European scale. Traditional undergraduate medical curricula need restructuring to account for the increasing amount of medical knowledge and rapid changes and developments in societies, nosology, therapy and IT. European undergraduate medical curricula should be harmonized not egalized, with a focus on inter-European sharing of resources, mobility, credit (allocation, accumulation and transfer), definition of European and trans-European mission statements, identification of quality metrics, advice on dealing with conflicting aims such as specialization and generalization, on communicating core knowledge instead of providing overabundance of information, and on introducing multifaceted teaching and learning methods, as well as providing strategies for life long learning. Sound medical education can no longer and nowhere be considered under the autonomous auspices of individual Medical Schools or national philosophies. It has to be perceived and structured as a competitive and flexible approach which promotes life long learning of teachers, students, physicians and other related staff with international awareness. It is stressed that student and staff mobility, as well as virtual mobility in the form of worldwide available teaching modules and expertise have to be incorporated into national medical curricula. This is to guarantee up-to-date education in support of patient demands, future professionality and competitiveness of students, physicians and Public Health System institutions. The formal approaches of traditional subject related curricula as well as problem based learning must be linked with quality approved state of the art ODL, evaluated international CME strategies and training in the utilization of IT in preparation of lifelong learning. Strategies for the use of IT need updating on a regular basis to diminish the gap between undergraduate and postgraduate medical education. General European perspectives of medical education are discussed in relation to ECTS, ODL, compulsory credited and evaluated CME and relicensing of physicians. Prime features of ETM--the most reputed and well-known European medical CME initiative fostering quality assured international awareness are described and recommended for local and nationwide implementation. Specific links of the Bonn undergraduate medical curriculum with credited and evaluated CME and imminent European strategies are detailed. The authors conclude that European universities not adapting at least some of the outlined curricular necessities will rapidly lose their competitiveness compared to other national and international Medical Schools. Harmonized European ethical mission statements and consequent utilization of IT deserve special considerations in this context.

Food increases the bioavailability of tolterodine but not effective exposure

The objective of this study was to investigate the influence of food on the pharmacokinetics of tolterodine, its active 5-hydroxymethyl metabolite (5-HM), and exposure to the active moiety (sum of unbound tolterodine + 5-HM) in healthy volunteers. Serum concentrations of tolterodine and 5-HM were measured for up to 12 hours after a single oral dose (2 mg) of tolterodine L-tartrate, administered either on an empty stomach or with a standardized medium-fat breakfast. All 23 subjects completing the study were classified as extensive metabolizers (phenotyped with debrisoquine). Pharmacokinetic data on tolterodine and the active moiety were evaluable for 22 subjects; all completing subjects were evaluable for 5-HM pharmacokinetics. Based on Cmax and AUC(infinity) ratios, relative bioavailability of tolterodine in the presence of food was 1.49 (90% confidence interval [CI], 1.35-1.71) and 1.53 (1.35-1.72), respectively. The pharmacokinetics of 5-HM and the active moiety were unaffected by food, as were the rates of drug absorption and terminal half-lives of tolterodine and 5-HM. Given that bioequivalence was observed for the active moiety underfed and fasting conditions, the authors concluded that coadministration of tolterodine with food is not expected to have any clinically relevant effects.

Treatment with antioxidants at onset of type 1 diabetes in children: a randomized, double-blind placebo-controlled study

BACKGROUND

In recent years different types of immune interventions have been tried at the onset of type 1 diabetes. Although some have shown effects, none have proven to be sufficiently effective to justify the inherent risks and side effects. Antioxidants have no or minimal side effects. If they can protect the beta cells against free oxygen radicals during the inflammatory process this would be a safe and cheap intervention. To evaluate this hypothesis a combination of various antioxidative agents was employed in a double-blind randomized study.

METHODS

The study group comprised 46 children aged 1-17 years at diagnosis. They were followed for 3 years: 2 years whilst taking the tablets and 1 year of follow-up. Twenty-four children were randomly allocated to active treatment with high doses of antioxidants and 22 children to placebo tablets. The tablets were the same size and tasted identical.

RESULTS

Twenty patients had for more than 1 month an insulin dose <0.5 U/kg in parallel with a normal HbA(1c) value and stable blood glucose values, but with no difference observed between those with and without active treatment. Nor was any significant difference observed regarding C-peptide values, fasting as well as stimulated. Whilst the antioxidants demonstrated no positive effect, they also had no negative side effects.

CONCLUSION

At diagnosis of type 1 diabetes in children, high doses of antioxidative agents have no effect either on the preservation of beta cell function or on metabolic balance.

The influence of curli, a MHC-I-binding bacterial surface structure, on macrophage-T cell interactions

Escherichia coli express thin surface fimbriae called curli which bind soluble matrix proteins and major histocompatibility complex (MHC)-I molecules. The present study addressed the ability of purified curli or curliated E. coli to influence peptide presentation on MHC-I, T cell proliferation and bacterial uptake by macrophages. In vitro studies with curli-proficient E. coli YMel and the isogenic curli-deficient strain YMel-1, both expressing the model antigen Crl-OVA, showed that curli expression by E. coli does not appear to influence the efficiency by which the bacteria are processed by murine macrophages for OVA(257-264) presentation on K(b). Furthermore, curli expression by E. coli did not influence the binding of exogenously added OVA(257-264) peptide to K(b) on the surface of prefixed macrophages. In addition, neither curliated nor non-curliated heat-killed bacteria influenced proliferation of either murine or human T cells stimulated with anti-CD3. Finally, curliated E. coli adhered to and were internalized by macrophages from C57BL/6 and MHC-I-deficient TAP1(-/-) mice equally well. Together these studies show that curli expression by E. coli does not appear to influence phagocytic processing of bacteria expressing Crl-OVA for OVA(257-264)/K(b) presentation, the binding of exogenously added OVA(257-264) to K(b) or T cell proliferation. In addition, although curli expression by E. coli enhances bacterial interaction with macrophages, curli interaction with MHC-I does not significantly contribute to this adherence.

Determination of absolute configuration of (pi-allyl) palladium complexes by NMR spectroscopy and stereoselective complexation

The chiral chelating ligand N,N'-bis(phenylethyl)bispidine (1) forms a rigid cavity which accommodates (pi-allyl)palladium species with high selectivity. In the resulting complex, the absolute configuration of the pi-allyl ligand can be determined by the detection in NMR spectra of a few unambiguous interligand NOEs. Dynamic processes involving the pi-allyl ligand can be investigated. Depending on the analytical target, ligand (S,S)-1 or (R,R)-1 may be used.

Translational and structural requirements of the early nodulin gene enod40, a short-open reading frame-containing RNA, for elicitation of a cell-specific growth response in the alfalfa root cortex

A diversity of mRNAs containing only short open reading frames (sORF-RNAs; encoding less than 30 amino acids) have been shown to be induced in growth and differentiation processes. The early nodulin gene enod40, coding for a 0.7-kb sORF-RNA, is expressed in the nodule primordium developing in the root cortex of leguminous plants after infection by symbiotic bacteria. Ballistic microtargeting of this gene into Medicago roots induced division of cortical cells. Translation of two sORFs (I and II, 13 and 27 amino acids, respectively) present in the conserved 5' and 3' regions of enod40 was required for this biological activity. These sORFs may be translated in roots via a reinitiation mechanism. In vitro translation products starting from the ATG of sORF I were detectable by mutating enod40 to yield peptides larger than 38 amino acids. Deletion of a Medicago truncatula enod40 region between the sORFs, spanning a predicted RNA structure, did not affect their translation but resulted in significantly decreased biological activity. Our data reveal a complex regulation of enod40 action, pointing to a role of sORF-encoded peptides and structured RNA signals in developmental processes involving sORF-RNAs.

Hypothalamic CART and serum leptin levels are reduced in the anorectic (anx/anx) mouse

Cocaine- and amphetamine-regulated transcript (CART) is expressed in the hypothalamus, and putative peptides encoded by CART potently inhibit feeding when administered centrally. CART is strongly down-regulated in the lateral hypothalamic area and the arcuate nucleus in animal models of obesity with disrupted leptin signaling. Here we have used in situ hybridization and immunohistochemistry to study CART expression in mice homozygous for the anorexia (anx) mutation which are characterized by a much reduced food intake and premature death. anx/anx mice had significantly decreased levels of CART mRNA label and peptide-immunoreactive cell bodies and fibers in the arcuate nucleus and a lower number of detectable CART-expressing cells in the dorsomedial hypothalamic nucleus/lateral hypothalamic area. Moreover, serum leptin levels were significantly lower in anx/anx mice compared to normal littermates, most likely due to the prominent depletion of body fat in these animals. The decrease in the anorexigenic agents leptin and CART, may reflect a compensatory down-regulation in response to the energy-deprived state of anx/anx mice. Alternatively, the reduced arcuate CART expression may be a consequence of a molecular defect in the arcuate nucleus of these animals.

Salmonella enterica serovar typhimurium-induced maturation of bone marrow-derived dendritic cells

Murine bone marrow-derived dendritic cells (DC) can phagocytose and process Salmonella enterica serovar Typhimurium for peptide presentation on major histocompatibility complex class I (MHC-I) and MHC-II molecules. To investigate if a serovar Typhimurium encounter with DC induces maturation and downregulates their ability to present antigens from subsequently encountered bacteria, DC were pulsed with serovar Typhimurium 24 h prior to coincubating with Escherichia coli expressing the model antigen Crl-OVA. Quantitating presentation of OVA epitopes contained within Crl-OVA showed that Salmonella-pulsed DC had a reduced capacity to process Crl-OVA-expressing E. coli for OVA(257-264)/K(b) and OVA(265-277)/I-A(b) presentation. In addition, time course studies of DC pulsed with Crl-OVA-expressing serovar Typhimurium showed that OVA(257-264)/K(b) complexes could stimulate CD8OVA T-hybridoma cells for <24 h following a bacterial pulse, while OVA(265-277)/I-A(b) complexes could stimulate OT4H T-hybridoma cells for >24 but <48 h. The phoP-phoQ virulence locus of serovar Typhimurium also influenced the ability of DC to process Crl-OVA-expressing serovar Typhimurium for OVA(265-277)/I-A(b) presentation but not for OVA(257-264)/K(b) presentation. Furthermore, pulsing of DC with serovar Typhimurium followed by incubation for 24 or 48 h altered surface expression of MHC-I, MHC-II, CD40, CD54, CD80, and CD86, generating a DC population with a uniform, high expression level of these molecules. Finally, neither the serovar Typhimurium phoP-phoQ locus nor lipopolysaccharides (LPS) containing lipid A modifications purified from phoP mutant strains had a different effect on DC maturation from that of wild-type serovar Typhimurium or purified wild-type LPS. Thus, these data show that Salmonella or Salmonella LPS induces maturation of DC and that this process is not altered by the Salmonella phoP virulence locus. However, phoP did influence OVA(265-277)/I-A(b) presentation by DC infected with Crl-OVA-expressing serovar Typhimurium when quantitated after 2 h of bacterial infection.

Interactions of the NADP(H)-binding domain III of proton-translocating transhydrogenase from escherichia coli with NADP(H) and the NAD(H)-binding domain I studied by NMR and site-directed mutagenesis

Using the purified NADP(H)-binding domain of proton-translocating Escherichia coli transhydrogenase (ecIII) overexpressed in (15)N- and (2)H-labeled medium, together with the purified NAD(H)-binding domain from E. coli (ecI), the interface between ecIII and ecI, the NADP(H)-binding site and the influence on the interface by NAD(P)(H) was investigated in solution by NMR chemical shift mapping. Mapping of the NADP(H)-binding site showed that the NADP(H) substrate is bound to ecIII in an extended conformation at the C-terminal end of the parallel beta-sheet. The distribution of chemical shift perturbations in the NADP(H)-binding site, and the nature of the interaction between ecI and ecIII, indicated that the nicotinamide moiety of NADP(H) is located near the loop comprising residues P346-G353, in agreement with the recently determined crystal structures of bovine [Prasad, G. S., et al. (1999) Nat. Struct. Biol. 6, 1126-1131] and human heart [White, A. W., et al. (2000) Structure 8, 1-12] transhydrogenases. Further chemical shift perturbation analysis also identified regions comprising residues G389-I406 and G430-V434 at the C-terminal end of ecIII's beta-sheet as part of the ecI-ecIII interface, which were regulated by the redox state of the NAD(P)(H) substrates. To investigate the role of these loop regions in the interaction with domain I, the single cysteine mutants T393C, R425C, G430C, and A432C were generated in ecIII and the transhydrogenase activities of the resulting mutant proteins characterized using the NAD(H)-binding domain I from Rhodospirillum rubrum (rrI). All mutants except R425C showed altered NADP(H) binding and domain interaction properties. In contrast, the R425C mutant showed almost exclusively changes in the NADP(H)-binding properties, without changing the affinity for rrI. Finally, by combining the above conclusions with information obtained by a further characterization of previously constructed mutants, the implications of the findings were considered in a mechanistic context.

[Technical improvements in bone densitometry]

The SBU-report no 127 "Mätning av bentäthet" [Measuring bone density] was published in 1995 and its conclusions are still valid. However, since then new treatment modalities have placed increasing demands on the diagnostic capability and performance of the apparatus used for bone densitometry. The most well-established and widely used technique for bone mineral determination is dual energy X-ray absorptiometry. Several international studies have shown that quantitative ultrasound should not be used for diagnosis or monitoring of osteoporosis. The reproducibility of one's method is important for monitoring, and the method's accuracy is important for diagnosis. Due to the limitations of the techniques and the slow turnover of the skeleton, repeated measurements are not meaningful until at least two years have passed. In order to maintain high quality in measurement results it is important to have trained personnel and to have a regular quality assurance program for the apparatus.

Association analysis with microsatellite and SNP markers does not support the involvement of BCL-2 in systemic lupus erythematosus in Mexican and Swedish patients and their families

We have described suggestive linkage between microsatellite markers within the cytogenetic region 18q21-23 and SLE, a region where linkage with other autoimmune diseases has also been detected. The Bcl-2 gene located within this region, is a candidate gene because of its role in apoptosis, a physiological mechanism that could be deregulated in autoimmune disease. Furthermore, several studies have found abnormalities of Bcl-2 expression in SLE patients. We therefore sought to determine if the Bcl-2 gene is involved in SLE by studying members of a large cohort of Mexican SLE patients (n = 378) and 112 Swedish simplex families. Using a microsatellite marker and two single nucleotide polymorphisms located within the gene, we were unable to detect association between Bcl-2 and SLE in either population. We also tested whether combinations of alleles of the Bcl-2 and IL-10.G microsatellites would increase the risk for SLE. Our results do not support such hypothesis. Our findings suggest that linkage between SLE and the 18q21-23 region is due to a gene other than Bcl-2.

Histologic evaluation of retrieved craniofacial implants

A retrieval study was performed on implants placed extraorally in the craniofacial region. The study included 19 implants retrieved from 16 patients. The implants were all stable at the time of removal. For various reasons, 5 of the implants were never loaded, whereas 14 of the implants had a known loading period of 3 months to 7 years 7 months. The reasons for removal varied but included the following: death in 1 case; poor results of the bone-anchored hearing aid in 7 cases; host-related reasons, varying from soft tissue irritation to infection or pain, in 6 cases; change of treatment plan in 1 case; and scheduled direct removal at the time of insertion in 1 case. The results of the histologic evaluation were similar to those reported in retrieval studies of a corresponding design used intraorally.

Neonatal exchange transfusion with heparinised whole blood or citrated composite blood: a prospective study

Heparinised blood should be kept as an available option for neonatal exchange transfusions.

Proton translocating nicotinamide nucleotide transhydrogenase from E. coli. Mechanism of action deduced from its structural and catalytic properties

Transhydrogenase couples the stereospecific and reversible transfer of hydride equivalents from NADH to NADP(+) to the translocation of proton across the inner membrane in mitochondria and the cytoplasmic membrane in bacteria. Like all transhydrogenases, the Escherichia coli enzyme is composed of three domains. Domains I and III protrude from the membrane and contain the binding site for NAD(H) and NADP(H), respectively. Domain II spans the membrane and constitutes at least partly the proton translocating pathway. Three-dimensional models of the hydrophilic domains I and III deduced from crystallographic and NMR data and a new topology of domain II are presented. The new information obtained from the structures and the numerous mutation studies strengthen the proposition of a binding change mechanism, as a way to couple the reduction of NADP(+) by NADH to proton translocation and occurring mainly at the level of the NADP(H) binding site.

Salmonella infection of bone marrow-derived macrophages and dendritic cells: influence on antigen presentation and initiating an immune response

Traditionally macrophages (MPhi) have been considered to be the key type of antigen presenting cells (APC) to combat bacterial infections by phagocytosing and destroying bacteria and presenting bacteria-derived antigens to T cells. However, data in recent years have demonstrated that dendritic cells (DC), at their immature stage of differentiation, are capable of phagocytosing particulate antigens including bacteria. Thus, DC may also be important APC for initiating an immune response to bacterial infections. Our studies focus on studying how DC and MPhi process antigens derived from bacteria with no known mechanism of phagosomal escape (i.e. Salmonella typhimurium) for T cell stimulation as well as what role these APC types have in Salmonella infection in vivo. Using an in vitro antigen processing and presentation assay with bone marrow-derived (BM) APC showed that, in addition to peritoneal elicited MPhi and BMMPhi, BMDC can phagocytose and process Escherichia coli and S. typhimurium for peptide presentation on major histocompatibility complex (MHC) class I (MHC-I) and class II MHC-II. These studies showed that both elicited peritoneal MPhi and BMMPhi use an alternate MHC-I presentation pathway that does not require the transporter associated with antigen processing (TAP) or the proteasome and involves peptide loading onto a preformed pool of post-Golgi MHC-I molecules. In contrast, DC process E. coli and S. typhimurium for peptide presentation on MHC-I using the cytosolic MHC-I presentation pathway that requires TAP, the proteasome and uses newly synthesized MHC-I molecules. We further investigated the interaction of Salmonella with BMDC and BMMPhi by analyzing surface molecule expression and cytokine secretion following S. typhimurium infection of BMDC and BMMPhi. These data reveal that Salmonella co-incubation with BMDC as well as BMMPhi results in upregulation of MHC-I and MHC-II as well as several co-stimulatory molecules including CD80 and CD86. Salmonella infection of BMDC or BMMPhi also results in secretion of cytokines including IL-6 and IL-12. Finally, injecting mice with BMDC that have been loaded in vitro with S. typhimurium primes naïve CD4(+) and CD8(+) T cells to Salmonella-encoded antigens. Taken together, our data suggest that DC may be an important type of APC that contributes to the immune response to Salmonella.

Isometric force and endurance in soleus muscle of thyroid hormone receptor-alpha(1)- or -beta-deficient mice

The specific role of each subtype of thyroid hormone receptor (TR) on skeletal muscle function is unclear. We have therefore studied kinetics of isometric twitches and tetani as well as fatigue resistance in isolated soleus muscles of R-alpha(1)- or -beta-deficient mice. The results show 20-40% longer contraction and relaxation times of twitches and tetani in soleus muscles from TR-alpha(1)-deficient mice compared with their wild-type controls. TR-beta-deficient mice, which have high thyroid hormone levels, were less fatigue resistant than their wild-type controls, but contraction and relaxation times were not different. Western blot analyses showed a reduced concentration of the fast-type sarcoplasmic reticulum Ca(2+)-ATPase (SERCa1) in TR-alpha(1)-deficient mice, but no changes were observed in TR-beta-deficient mice compared with their respective controls. We conclude that in skeletal muscle, both TR-alpha(1) and TR-beta are required to get a normal thyroid hormone response.

Long-term results and functional outcome after Ripstein rectopexy

PURPOSE

The aim of this study was to evaluate operative mortality, morbidity, and functional results after Ripstein rectopexy for rectal prolapse and internal rectal intussusception.

METHODS

Sixty-nine patients with rectal prolapse and 43 with internal rectal intussusception were included. All patient records were studied and complications registered. Long-term follow-up was possible in 105 patients and performed by clinical examination and standardized interview, telephone interview, or patient records. Seventy-six patients were prospectively evaluated, comparing bowel function before and after rectopexy.

RESULTS

There was no operative mortality. Operative morbidity was 33 percent, and most complications were minor. Severe early complications included one large-bowel obstruction and one transient ureteric stenosis. Median time of follow-up was seven years in patients with rectal prolapse and 5.4 years in patients with internal rectal intussusception. Late complications included two rectovaginal fistulas and one lethal sigmoid fecaloma. Five patients underwent subtotal colectomy for severe constipation. There was one recurrent prolapse (1.6 percent). Functional evaluation showed that incontinence improved (P = 0.049), whereas the number of bowel movements per week decreased (P < 0.001). Frequency of emptying difficulties did not change significantly in patients with rectal prolapse but increased in patients with internal rectal intussusception (P = 0.038).

CONCLUSION

Ripstein rectopexy can be performed with low mortality and recurrence rate, but with a high early complication rate. There were also some serious late complications. Continence was improved, although increased constipation was a problem in some patients, especially among those with internal rectal intussusception.

Transient but not permanent neonatal diabetes mellitus is associated with paternal uniparental isodisomy of chromosome 6

OBJECTIVES

The factors determining the pathogenesis of transient and permanent neonatal diabetes mellitus are poorly characterized. The purpose of this study was to examine the role of chromosome 6 in the pathogenesis of neonatal diabetes mellitus and to detect differences between these 2 phenotypes.

METHODS

Microsatellite markers (D6S334, D6S286, D6S310, D6S308, D6S292, D6S311, and D6S403) and human leukocyte antigen DQ alleles were examined using polymerase chain reaction and DNA fragment electrophoresis in 3 patients with transient and 3 patients with permanent neonatal diabetes mellitus. Humoral markers of islet cell autoimmunity and clinical characteristics were analyzed in the 2 groups.

RESULTS

A patient with transient neonatal diabetes mellitus (TND) and macroglossia carrying paternal uniparental isodisomy (UPD) of chromosome 6 has been identified. The isodisomy affected the whole chromosome; no maternal chromosome 6 sequences were detected. The permanent neonatal diabetes mellitus cases and the other 2 cases with TND did not have UPD. None of the patients had high-risk type 1 diabetes human leukocyte antigen DQ alleles and most infants were negative for islet cell-specific autoantibodies indicating that none of the 2 forms of neonatal diabetes mellitus is likely to be of autoimmune origin. An association of TND and persistent granulocytopenia is described for the first time.

CONCLUSIONS

We propose that transient and permanent forms of neonatal diabetes mellitus have different genetic background and represent different disease entities. TND is associated with UPD of chromosome 6 suggesting that an imprinted gene on chromosome 6 is responsible for this phenotype. It seems that 2 copies of the paternal allele are necessary for the development of TND; therefore, it is likely that overexpression of a putative gene located on chromosome 6 alters pancreatic beta-cell maturation and insulin secretion.

Positive atopy patch test reactions to Pityrosporum orbiculare in atopic dermatitis patients

BACKGROUND

Pityrosporum orbiculare, although a part of our normal cutaneous microflora, can cause skin infections and induce specific immunoglobulin (Ig) E antibodies in atopic dermatitis patients. P. orbiculare is therefore considered to be one of the trigger factors for atopic dermatitis.

OBJECTIVE

To investigate if P. orbiculare can induce an eczematous reaction in atopic dermatitis patients, seborrhoeic dermatitis patients and healthy controls.

METHODS

Fifteen atopic dermatitis patients, eight seborrhoeic dermatitis patients and eight healthy controls were patch tested with extract of P. orbiculare on non-lesional, tape-stripped skin of the back. NaCl was used as a negative control. The patch tests were evaluated after 24, 48 and 72 h. Skin biopsies were taken from P. orbiculare patch test sites at 24 h and 72 h, from NaCl patch test sites at 72 h, from non-lesional skin and, in the atopic dermatitis patients, also from lesional skin. The skin biopsies were investigated with immunohistochemical techniques. P. orbiculare-specific IgE in serum was analysed with RAST.

RESULTS

Specific IgE to P. orbiculare was found in serum from 13/15 atopic dermatitis patients and in eight of them a positive patch test reaction to P. orbiculare was observed, with a maximal reaction at 48 h. Significantly higher serum levels of P. orbiculare-specific IgE were detected in patch test-positive compared with patch test-negative atopic dermatitis patients (P < 0. 01). The seborrhoeic dermatitis patients and healthy controls were RAST and patch test-negative for P. orbiculare. In the patch test-positive atopic dermatitis patients an infiltration of CD4+ T cells and eosinophils was observed at the P. orbiculare patch test sites together with an upregulation of ICAM-1 and HLA-DR expression.

CONCLUSIONS

P. orbiculare can induce an eczematous reaction in sensitized atopic dermatitis patients and may be an important trigger factor in these patients. The P. orbiculare patch test can be of diagnostic value in this subgroup of atopic dermatitis patients.