Feasibility of anorectal chlamydia testing in women: a cross-sectional survey among general practitioners

BACKGROUND

Anorectal Chlamydia trachomatis (CT) may be clinically relevant for women in general practice. Although anorectal CT testing in this setting may prevent underdiagnosis and undertreatment, its feasibility is questioned as GPs currently rarely order anorectal CT tests, for yet unknown reasons.

OBJECTIVE

To explore the feasibility of anorectal CT testing in women in general practice.

METHODS

GPs across the Netherlands were invited directly (n = 1481) and by snowball sampling (n = 330) to join an online cross-sectional survey that asked about the acceptability of and barriers for (standard) anorectal testing in women during CT-related consultations. Data were analysed with univariable and multivariable logistic regression models.

RESULTS

The questionnaire was opened by 514 respondents (28%, 514/1811) and 394 fully completed it. GPs' acceptability of anorectal testing by either self-sampling or provider-sampling was high (86%). Twenty-eight percent of GPs felt neutral, and 43% felt accepting towards standard anorectal testing. Nevertheless, 40% of GPs had never tested for anorectal CT in women, which was associated with a reported difficulty in asking about anal sex (odds ratio [OR]: 3.07, 95% confidence interval [CI]: 1.21-7.80), infrequency of anal sexual history taking (OR: 11.50, 95% CI: 6.39-20.72), low frequency of urogenital CT testing (OR 3.44, 95%-CI: 1.86-6.38) and with practicing in a non-urban area (OR: 2.27, 95% CI: 1.48-3.48). Acceptability of anorectal testing was not associated with the studied factors.

CONCLUSION

This quantitative survey shows that anorectal CT testing is feasible based on its acceptability, but is likely hindered by a lower awareness of (anorectal) CT in GPs.

NMR in the SPINE Structural Proteomics project

This paper describes the developments, role and contributions of the NMR spectroscopy groups in the Structural Proteomics In Europe (SPINE) consortium. Focusing on the development of high-throughput (HTP) pipelines for NMR structure determinations of proteins, all aspects from sample preparation, data acquisition, data processing, data analysis to structure determination have been improved with respect to sensitivity, automation, speed, robustness and validation. Specific highlights are protonless (13)C-direct detection methods and inferential structure determinations (ISD). In addition to technological improvements, these methods have been applied to deliver over 60 NMR structures of proteins, among which are five that failed to crystallize. The inclusion of NMR spectroscopy in structural proteomics pipelines improves the success rate for protein structure determinations.

Detrusor overactivity in spina bifida: How long does it need to be treated?

AIMS

To determine whether a lasting therapeutic effect can be expected from long-term antimuscarinic therapy for neurogenic detrusor overactivity in spina bifida and to answer the question whether detrusor overactivity in spina bifida children with detrusor/sphincter dyssynergia is primarily based on the neuropathy or, in part, can be a secondary detrusor reaction to the functional urethral obstruction.

METHODS

Fifteen spina bifida patients, aged between 1 and 12 years, all on a regime of clean intermittent catheterisation (CIC) and oxybutynin since shortly after birth, underwent three consecutive urodynamic studies (UDS). One prestudy UDS for treatment control, one UDS after withdrawal of oxybutynin for 3-5 days and one UDS after reinstallment of oxybutynin treatment. Urodynamic results were compared concerning detrusor overactivity, cystometric bladder capacity, and compliance.

RESULTS

Detrusor overactivity was seen in two patients on the prestudy UDS. After several days of withdrawal of oxybutynin overactivity was seen in 11 patients. After oxybutynin withdrawal, bladder compliance was within safe margins for two patients only, after reinstallment, safe vesical pressures were seen in 11 patients.

CONCLUSION

The functional obstruction due to detrusor/sphincter dyssynergia has been by-passed chronically in all these children by CIC and oxybutynin. Due to the fact that detrusor overactivity recurs immediately after withdrawal of medication after long-term treatment with oxybutynin, one can conclude that there is no long-lasting therapeutic effect of pharmacological suppression. This suggests that in children with detrusor/sphincter dyssynergia, detrusor overactivity is primarily of neuropathic origin.

[Urine incontinence in childhood; the importance of a good micturition history]

Four children, three girls aged 9, 5.5 and 6.5 years, and a boy aged 8 years, suffered from urinary incontinence. The underlying conditions, urge syndrome with urge incontinence, ectopic ureter, meatus stenosis, and pelvic floor dysfunction, respectively, were identified and treated, after which the children were no longer incontinent. Diurnal incontinence is present in 2-3% of 7-year-olds. Incontinence is accompanied by recurrent urinary tract infections and vesicoureteric reflux in 40% of cases. A combination of these two disorders can lead to impaired renal function. Especially in girls, involuntary urine loss is usually based on dysfunctional voiding, a non-neurogenic coordination problem between the detrusor muscle of the bladder and the pelvic floor. A careful history is the most important tool in reaching the correct diagnosis.

NMR structure of cysteinyl-phosphorylated enzyme IIB of the N,N′-diacetylchitobiose-specific phosphoenolpyruvate-dependent phosphotransferase system of Escherichia coli

The determination by NMR of the solution structure of the phosphorylated enzyme IIB (P-IIB(Chb)) of the N,N'-diacetylchitobiose-specific phosphoenolpyruvate-dependent phosphotransferase system of Escherichia coli is presented. Most of the backbone and side-chain resonances were assigned using a variety of mostly heteronuclear NMR experiments. The remaining resonances were assigned with the help of the structure calculations.NOE-derived distance restraints were used in distance geometry calculations followed by molecular dynamics and simulated annealing protocols. In addition, combinations of ambiguous restraints were used to resolve ambiguities in the NOE assignments. By combining sets of ambiguous and unambiguous restraints into new ambiguous restraints, an error function was constructed that was less sensitive to information loss caused by assignment uncertainties. The final set of structures had a pairwise rmsd of 0.59 A and 1.16 A for the heavy atoms of the backbone and side-chains, respectively. Comparing the P-IIB(Chb) solution structure with the previously determined NMR and X-ray structures of the wild-type and the Cys10Ser mutant shows that significant differences between the structures are limited to the active-site region. The phosphoryl group at the active-site cysteine residue is surrounded by a loop formed by residues 10 through 16. NOE and chemical shift data suggest that the phosphoryl group makes hydrogen bonds with the backbone amide protons of residues 12 and 15. The binding mode of the phosphoryl group is very similar to that of the protein tyrosine phosphatases. The differences observed are in accordance with the presumption that IIB(Chb) has to be more resistant to hydrolysis than the protein tyrosine phosphatases. We propose a proton relay network by which a transfer occurs between the cysteine SH proton and the solvent via the hydroxyl group of Thr16.

[Primary peritonitis due to Streptococcus pneumoniae in childhood]

Three patients, two boys of 5 months and 6 years and one girl aged 4 years, presented with acute abdominal pain, vomiting and fever, suggesting peritonitis. Imaging examinations (abdominal survey roentgenogram and (or) echography), exploratory laparotomy (in two patients) and blood cultures with growth of Streptococcus pneumoniae led to the diagnosis of primary peritonitis. Intravenous antibiotics led to recovery, in one patient complicated by paralytic ileus, which was treated surgically. Primary peritonitis is a rare condition which should be considered in the differential diagnosis of children with an acute abdominal syndrome. Conditions requiring surgery should be excluded by imaging examinations or laparotomy. When the diagnosis is confirmed by paracentesis or laparotomy, antibiotic treatment has to be started.

The NMR side-chain assignments and solution structure of enzyme IIBcellobiose of the phosphoenolpyruvate-dependent phosphotransferase system of Escherichia coli

The assignment of the side-chain NMR resonances and the determination of the three-dimensional solution structure of the C10S mutant of enzyme IIBcellobiose (IIBcel) of the phosphoenolpyruvate-dependent phosphotransferase system of Escherichia coli are presented. The side-chain resonances were assigned nearly completely using a variety of mostly heteronuclear NMR experiments, including HCCH-TOCSY, HCCH-COSY, and COCCH-TOCSY experiments as well as CBCACOHA, CBCA(CO)NH, and HBHA(CBCA)(CO)NH experiments. In order to obtain the three-dimensional structure, NOE data were collected from 15N-NOESY-HSQC, 13C-HSQC-NOESY, and 2D NOE experiments. The distance restraints derived from these NOE data were used in distance geometry calculations followed by molecular dynamics and simulated annealing protocols. In an iterative procedure, additional NOE assignments were derived from the calculated structures and new structures were calculated. The final set of structures, calculated with approximately 2000 unambiguous and ambiguous distance restraints, has an rms deviation of 1.1 A on C alpha atoms. IIBcel consists of a four stranded parallel beta-sheet, in the order 2134. The sheet is flanked with two and three alpha-helices on either side. Residue 10, a cysteine in the wild-type enzyme, which is phosphorylated during the catalytic cycle, is located at the end of the first beta-strand. A loop that is proposed to be involved in the binding of the phosphoryl-group follows the cysteine. The loop appears to be disordered in the unphosphorylated state.

Enzyme IIBcellobiose of the phosphoenol-pyruvate-dependent phosphotransferase system of Escherichia coli: backbone assignment and secondary structure determined by three-dimensional NMR spectroscopy

The assignment of backbone resonances and the secondary structure determination of the Cys 10 Ser mutant of enzyme IIBcellobiose of the Escherichia coli cellobiose-specific phosphoenol-pyruvate-dependent phosphotransferase system are presented. The backbone resonances were assigned using 4 triple resonance experiments, the HNCA and HN(CO)CA experiments, correlating backbone 1H, 15N, and 13C alpha resonances, and the HN(CA)CO and HNCO experiments, correlating backbone 1H,15N and 13CO resonances. Heteronuclear 1H-NOE 1H-15N single quantum coherence (15N-NOESY-HSQC) spectroscopy and heteronuclear 1H total correlation 1H-15N single quantum coherence (15N-TOCSY-HSQC) spectroscopy were used to resolve ambiguities arising from overlapping 13C alpha and 13CO frequencies and to check the assignments from the triple resonance experiments. This procedure, together with a 3-dimensional 1H alpha-13C alpha-13CO experiment (COCAH), yielded the assignment for all observed backbone resonances. The secondary structure was determined using information both from the deviation of observed 1H alpha and 13C alpha chemical shifts from their random coil values and 1H-NOE information from the 15N-NOESY-HSQC. These data show that enzyme IIBcellobiose consists of a 4-stranded parallel beta-sheet and 5 alpha-helices. In the wild-type enzyme IIBcellobiose, the catalytic residue appears to be located at the end of a beta-strand.

X-ray structure of phospholipase A2 complexed with a substrate-derived inhibitor

Phospholipases A2 play a part in a number of physiologically important cellular processes such as inflammation, blood platelet aggregation and acute hypersensitivity. These processes are all initiated by the release of arachidonic acid from cell membranes which is catalysed by intracellular phospholipases A2 and followed by conversion of arachidonic acid to prostaglandins, leukotrienes or thromboxanes. An imbalance in the production of these compounds can lead to chronic inflammatory diseases such as rheumatoid arthritis and asthma. Inhibitors of phospholipase A2 might therefore act to reduce the effects of inflammation, so structural information about the binding of phospholipase A2 to its substrates could be helpful in the design of therapeutic drugs. The three-dimensional structure is not known for any intracellular phospholipase A2, but these enzymes share significant sequence homology with secreted phospholipases, for which some of the structures have been determined. Here we report the structure of a complex between an extracellular phospholipase A2 and a competitively inhibiting substrate analogue, which reveals considerable detail about the interaction and suggests a mechanism for catalysis by this enzyme.