Polysomnographic and actigraphic evidence of sleep fragmentation in patients with irritable bowel syndrome

STUDY OBJECTIVE: To characterize the function and quality of sleep in patients with irritable bowel syndrome (IBS). DESIGN: A prospective study with a historic comparison group. SETTING: A regional hospital that also serves as a tertiary referral center. PATIENTS: Eighteen patients with IBS and a comparison group of 20 matched adults with mild benign snoring. INTERVENTIONS: A polysomnography study and a wrist actigraphy study. MEASUREMENTS: All subjects underwent sleep studies and completed self-report questionnaires (IBS severity, psychosocial variables, sleep function, and Epworth Sleepiness Scale). Fourteen IBS and 11 comparison patients underwent actigraphy. RESULTS: The IBS patients had more than 70% less slow-wave stage sleep (4.5 +/- 7.3% vs 19.3 +/- 12.9%; P = 0.006), compensated by increased stage 2 sleep (72.2 +/- 6.6% vs 60.1 +/- 16.8%; P = 0.01). The IBS group had significant sleep fragmentation with a significantly higher arousal and awakening index (P < 0.001), a longer wake period after sleep onset (P = 0.02), and more downward shifts to lighter sleep stages (P = 0.01). The 4-night actigraphy study supported the polysomnography findings. The sleep fragmentation index was significantly higher (P = 0.008) in the IBS group. The IBS patients reported greater daytime sleepiness (9.0 +/- 4.8 vs 6.4 +/- 4.8, Epworth Sleepiness Scale score, P < 0.01) and greater impairment in quality of life, which correlated significantly with the sleep fragmentation indexes. The difference between the groups was not due to differences in baseline anxiety/depression levels. CONCLUSIONS: Patients with IBS have impaired sleep quality, reduced slow-wave sleep activity, and significant sleep fragmentation. The cause-and-effect relationship of these findings with patients' daytime symptoms should be studied further.     

Risk factors,clinical course and outcomes of pregnancy-related group A streptococcal infections: retrospective 13-year cohort study

Objectives

To investigate the incidence, risk factors, clinical course and outcomes of pregnancy-related group A streptococcus (GAS) infection.

Methylation alterations of the MyoD1 upstream region are predictive of subclassification of human rhabdomyosarcomas.

MyoD1 expression is a distinguishing characteristic of rhabdomyosarcoma. In this study, distinct methylation alterations were identified in the 5'' flanking region of the MyoD1 gene from the two major subtypes, ie, alveolar and embryonal rhabdomyosarcoma. The MyoD1 methylation patterns of 26 rhabdomyosarcomas were compared with that of normal skeletal muscle and nonmuscle specimens by Southern blot analysis using methylation-sensitive restriction enzymes HhaI and HpaII. A 5-kb region immediately upstream of the MyoD1 coding sequence was found to be methylated in adult muscle and all nonmuscle tissues tested. The MyoD1 upstream region was unmethylated in the majority of the alveolar rhabdomyosarcomas (13 of 15, 87%) examined in this study. In contrast, 10 of 11 (91%) embryonal rhabdomyosarcomas showed a methylation pattern that was also observed in fetal muscle cells, in which the CpG sites in the MyoD1 upstream region were partially methylated. Our data suggest that the methylation status of the MyoD1 upstream CpG sites may be related to rhabdomyosarcoma tumorigenesis and may have valuable implications for its differential diagnosis.     

Levels of Expression and Immunogenicity of Attenuated Salmonella enterica Serovar Typhimurium Strains Expressing Escherichia coli Mutant Heat-Labile Enterotoxin

The effects of heterologous gene dosage as well as Salmonella typhimurium strain variability on immune response toward both the heterologous antigen, the nontoxic mutant of the Escherichia coli heat-labile enterotoxin LTK63, and the carrier Salmonella strain have been analyzed. Effects of a single integration into the host DNA and different-copy-number episomal vectors were compared in S. typhimurium Δcya Δcrp Δasd strains of two different serotypes, UK-1 and SR-11. Expression of the enterotoxin in the different Salmonella isolates in vitro was found to vary considerably and, for the episomal vectors, to correlate with the plasmid copy number. LTK63-specific serum immunoglobulin G (IgG) and mucosal immunoglobulin A (IgA) antibodies were highest in mice immunized with the high-level-expression strain. High anti-LTK63 IgG and IgA titers were found to correspond to higher anti-Salmonella immunity, suggesting that LTK63 exerts an adjuvant effect on response to the carrier. Statistically significant differences in anti-LTK63 immune response were observed between groups of mice immunized with the attenuated Δcya Δcrp UK-1 and SR-11 derivatives producing the antigen at the same rate. These data indicate that the same attenuation in S. typhimurium strains of different genetic backgrounds can influence significantly the immune response toward the heterologous antigen. Moreover, delivery of the LTK63 enterotoxin to the immune system by attenuated S. typhimurium strains is effective only when synthesis of the antigen is very high during the initial phase of invasion, while persistence of the S. typhimurium strain in deep tissues has only marginal influence.

Enterotoxigenic Escherichia coli strains produce a plasmid-encoded heat-labile enterotoxin (LT) (15, 34) related to cholera toxin (CT) (9, 35). LT is composed of two subunits, A and B, which are exported to the periplasmic space, where they assemble into an AB₅ multimeric complex (16). Several mutants of LT-A have been constructed, and in particular, a nontoxic mutant which contains a substitution of serine 63 with lysine (LTK63) has been shown to maintain the structural and immunogenic properties of wild-type LT (21, 27, 28). LTK63 has also been found to display the strong mucosal adjuvant activity pertaining to wild-type LT. Efficient induction of mucosal immune response, specifically in the mouse vagina, has been achieved via the intranasal route of immunization (10). For the development of oral vaccines, however, it would be desirable to exploit the properties of LTK63 for enhancing antigen-specific immune response in the intestinal mucosa by means of oral delivery of the potent mucosal adjuvant.Oral delivery of antigens by live vaccines is known to lead to a more effective production of antigen-specific antibodies in mucosal secretions than oral administration of the soluble antigen (36, 39). Several antigen delivery systems which use as carriers mutant intracellular pathogens that have lost the ability to persist and produce the disease while retaining limited growth in vivo have been developed. In particular, attenuated Salmonella mutants are suitable immunological carriers for virulence determinants from other enteric bacteria in that they can induce humoral immune response selectively at the site of colonization, the gut mucosa. Vaccine strains of Salmonella have been successfully attenuated by introducing different types of mutations (5, 8, 23, 26). Notably, Salmonella strains with a galactose epimerase (galE) mutation (18) or deletions in genes for the biosynthesis of aromatic compounds (aro mutants) (11, 12, 17, 19) or in the adenylate cyclase (cya) and cyclic AMP receptor protein (crp) genes (6) are the most extensively characterized.Delivery of the B subunit of the E. coli enterotoxin (LT-B) by a galE mutant of Salmonella typhimurium has been shown to elicit low levels of anti-LT-B serum and mucosal antibodies. Since the vector used for expression of LT-B was rapidly lost in vivo, i.e., in the absence of the antibiotic required for selection of the plasmid, the level of immune response could be correlated only with the amount of antigen expressed during the initial phase of invasion (3).Recently, direct comparison between the aroA aroD/pnirB and the Δcya Δcrp Δasd/asd⁺ delivery systems for the ability to induce humoral and cellular immunity after a single immunization showed that the former vaccine strain had greater potential as a carrier for antigen delivery (20). However, the balanced lethal asd system for in vivo selection of plasmids expressing heterologous antigens in the attenuated Δcya Δcrp Δasd strains is still very attractive in that asd⁺ plasmids do not require antibiotic resistance markers for selection while stably maintained in vivo (24). In addition, the Δcya Δcrp Δasd/asd⁺ delivery system has been reported to induce protective immunity against several pathogens (25, 29, 40). Most of these studies have restricted analysis of the immune response to antigens expressed from the same asd⁺ plasmid carried by Δcya Δcrp Δasd mutants usually of the same S. typhimurium serotype. In this work, we have analyzed the influence of heterologous gene dosage, and thus level of expression, as well as S. typhimurium strain variability on immune response toward both the heterologous antigen, a nontoxic mutant of E. coli LT, and the carrier Salmonella strain. Effects of a single integration into the host DNA and episomal vectors at different copy numbers were compared in S. typhimurium strains of two different Δcya Δcrp Δasd serotypes, UK-1 and SR-11.     

Stress-induced analgesia: adaptive pain suppression

In this paper we have examined the phenomenon of stress-induced analgesia. We have described the procedures used to measure analgesia and have suggested that the tests can be designed not only to indicate changes in pain threshold but also to allow for the determination of the capacity to execute adaptive behavior. Aside from enabling the analysis of responses, tests that induce reflexive as well as nonreflexive behavior may have the capacity to separate the more complex aspects of pain such as the possible presence of two components of pain, sensory/discriminative and motivational/affective. These components may be of fundamental importance for any attempt to understand the biological significance of SIA. Our examination of the neurotransmitter and neuropeptide systems has revealed that they are affected by the same manipulations that induce SIA. These amines and perhaps peptides play an integral role in learning, motivation, and performance. We conclude that the functional advantage of a reduction of pain during stressful situations is significant because it allows the animal to react in threatening and perhaps critical situations as if there were no pain. Once the pain system is inhibited, other systems modulate and mediate adaptive responses that expedite the survival of the animal.     

Veränderungen von Mäusenieren nach experimenteller Infektion mit Mucambo-Virus

Summary The purpose of this study was to determine whether autoimmune nephritis in rats affects subsequent generations. Moreover, it was planned to study the nature of the changes in the kidneys in subsequent generations of rats. In these experiments eight generations of rats were investigated. The first five generations were immunized with a mixture of -Streptococcus hemolyticus with an emulsion of renal cortical substance; the rats were given from 4 to 8 injections. After the fifth generation the animals were not immunized, but their nephritis was considerably more pronounced than in their parents. In the 6th and 8th generations there was a sharp rise in the number of animals that died, mainly pregnant rats and newborns. In the course of the experiments, the animals were found to have hypertension, elevated blood nitrogen and proteinuria. A morphological investigation of the rats of the 6th, 7th, and 8th generations that were not immunized, but were born of immunized parents, revealed membranous-proliferative glomerulonephritis, which according to its clinical course and morphological data resembled the nephrotic syndrome the mixed type of human glomerulonephritis.

---

Zusammenfassung Die Untersuchungen über den Generationswandel der Autoimmunnephritis der Ratte erstreckten sich über 8 Generationen. Bei den ersten 5 Generationen wurde durch eine 4–8malige Injektion einer Mischung aus beta-hämolytischen Streptokokken mit einer Emulsion aus Nierenrindengewebe eine Immunnephritis erzeugt. Die Ratten der 6. bis 8. Generation erhielten keine immunisierenden Injektionen. Trotzdem kam es in der 6. und 8. Generation zu einem akuten Anstieg der Spontantodesrate besonders unter den graviden und neugeborenen Versuchstieren. Klinisch führte die Immun-Nephritis zu einem Blutdruckanstieg, einer Proteinurie und Erhöhung des Harnstoffes. Histologisch entsprachen die Nierenbefunde der 6.–8. Generation einer membranösen proliferativen Glomerulonephritis.

     

Comparative evaluation of three commercial products and counterimmunoelectrophoresis for the detection of antigens in cerebrospinal fluid.

Three commercial products and counterimmunoelectrophoresis were evaluated for their ability to detect microbial antigens of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae in cerebrospinal fluid from 157 patients suspected of having meningitis. Thirty-four patients were diagnosed as having bacterial meningitis by culture, microscopy, or antigen detection. The overall results showed the following detection percentages; counterimmunoelectrophoresis, 76%; Phadebact CSF, 76%; Directigen, 82%, and Bactigen, 93%. The results with purified antigen revealed that latex agglutination was more sensitive than coagglutination, which in turn was more sensitive than counterimmunoelectrophoresis.