Higher rates of cefiderocol resistance among NDM producing Klebsiella bloodstream isolates applying EUCAST over CLSI breakpoints

BACKGROUND

Cefiderocol is generally active against carbapenem-resistant Klebsiella spp. (CRK) with higher MICs against metallo-beta-lactamase producers. There is a variation in cefiderocol interpretive criteria determined by EUCAST and CLSI. Our objective was to test CRK isolates against cefiderocol and compare cefiderocol susceptibilities using EUCAST and CLSI interpretive criteria.

METHODS

A unique collection (n = 254) of mainly OXA-48-like- or NDM-producing CRK bloodstream isolates were tested against cefiderocol with disc diffusion (Mast Diagnostics, UK). Beta-lactam resistance genes and multilocus sequence types were identified using bioinformatics analyses on complete bacterial genomes.

RESULTS

Median cefiderocol inhibition zone diameter was 24 mm (interquartile range [IQR] 24-26 mm) for all isolates and 18 mm (IQR 15-21 mm) for NDM producers. We observed significant variability between cefiderocol susceptibilities using EUCAST and CLSI breakpoints, such that 26% and 2% of all isolates, and 81% and 12% of the NDM producers were resistant to cefiderocol using EUCAST and CLSI interpretive criteria, respectively.

CONCLUSIONS

Cefiderocol resistance rates among NDM producers are high using EUCAST criteria. Breakpoint variability may have significant implications on patient outcomes. Until more clinical outcome data are available, we suggest using EUCAST interpretive criteria for cefiderocol susceptibility testing.

High prevalence of ArmA-16S rRNA methyltransferase among aminoglycoside-resistant Klebsiella pneumoniae bloodstream isolates

Introduction. Aminoglycosides are used for the treatment of carbapenemase-producing Klebsiella pneumoniae (CPK) infections. 16S rRNA methyltransferases (RMTs) confer resistance to all aminoglycosides and are often cocarried with NDM.Hypothesis/Gap Statement. There is a dart of studies looking at the aminoglycoside resistance mechanisms for invasive CPK isolates, particularly in OXA-48 endemic settings.Aim. We aimed to determine the prevalence of RMTs and their association with beta lactamases and MLSTs amongst aminoglycoside-resistant CPK bloodstream isolates in an OXA-48 endemic setting.Methodology. CPK isolates (n=181), collected as part of a multicentre cohort study, were tested for amikacin, gentamicin and tobramycin susceptibility using custom-made sensititre plates (GN2XF, Thermo Fisher Scientific). All isolates were previously subjected to whole-genome sequencing. Carbapenemases, RMTs, MLSTs and plasmid incompatibility groups were detected on the assembled genomes.Results. Of the 181 isolates, 109(60 %) were resistant to all three aminoglycosides, and 96 of 109(88 %) aminoglycoside-resistant isolates carried an RMT (85 ArmA, 10 RmtC, 4 RmtF1; three isolates cocarried ArmA and RmtC). Main clonal types associated with ArmA were ST2096 (49/85, 58 %) and ST14 (24/85, 28 %), harbouring mainly OXA-232 and OXA-48 +NDM, respectively. RmtC was cocarried with NDM (5/10) on ST395, and NDM +OXA-48 or NDM +KPC (4/10) on ST14, ST15 and ST16. All RMT producers also carried CTX-M-15, and the majority cocarried SHV-106, TEM-150 and multiple other antibiotic resistance genes. The majority of the isolates harboured a combination of IncFIB, IncH and IncL/M type plasmids. Non-NDM producing isolates remained susceptible to ceftazidime-avibactam.Conclusion. Aminoglycoside resistance amongst CPK bloodstream isolates is extremely common and mainly driven by clonal spread of ArmA carried on ST2096 and ST14, associated with OXA-232 and OXA48 +NDM carriage, respectively.

Characteristics and outcomes of carbapenemase harbouring carbapenem-resistant Klebsiella spp. bloodstream infections: a multicentre prospective cohort study in an OXA-48 endemic setting

A prospective, multicentre observational cohort study of carbapenem-resistant Klebsiella spp. (CRK) bloodstream infections was conducted in Turkey from June 2018 to June 2019. One hundred eighty-seven patients were recruited. Single OXA-48-like carbapenemases predominated (75%), followed by OXA-48-like/NDM coproducers (16%). OXA-232 constituted 31% of all OXA-48-like carbapenemases and was mainly carried on ST2096. Thirty-day mortality was 44% overall and 51% for ST2096. In the multivariate cox regression analysis, SOFA score and immunosuppression were significant predictors of 30-day mortality and ST2096 had a non-significant effect. All OXA-48-like producers remained susceptible to ceftazidime-avibactam.

Strengths and caveats of identifying resistance genes from whole genome sequencing data

INTRODUCTION

Antimicrobial resistance (AMR) continues to present major challenges to modern healthcare. Recent advances in whole-genome sequencing (WGS) have made the rapid molecular characterization of AMR a realistic possibility for diagnostic laboratories; yet major barriers to clinical implementation exist.

AREAS COVERED

We describe and compare short- and long-read sequencing platforms, typical components of bioinformatics pipelines, tools for AMR gene detection and the relative merits of read- or assembly-based approaches. The challenges of characterizing mobile genetic elements from genomic data are outlined, as well as the complexities inherent to the prediction of phenotypic resistance from WGS. Practical obstacles to implementation in diagnostic laboratories, the critical role of quality control and external quality assurance, as well as standardized reporting standards are also discussed. Future directions, such as the application of machine-learning and artificial intelligence algorithms, linked to clinically meaningful outcomes, may offer a new paradigm for the clinical application of AMR prediction.

EXPERT OPINION

AMR prediction from WGS data presents an exciting opportunity to advance our capacity to comprehensively characterize infectious pathogens in a rapid manner, ultimately aiming to improve patient outcomes. Collaborative efforts between clinicians, scientists, regulatory bodies and healthcare administrators will be critical to achieve the full promise of this approach.

Burkholderia pseudomallei Clinical Isolates Are Highly Susceptible In Vitro to Cefiderocol, a Siderophore Cephalosporin

Cefiderocol is a cephalosporin designed to treat multidrug-resistant Gram-negative infections. By forming a chelated complex with ferric iron, cefiderocol is transported into the periplasmic space via bacterial iron transport systems and primarily binds to penicillin-binding protein 3 (PBP3) to inhibit peptidoglycan synthesis. This mode of action results in cefiderocol having greater in vitro activity against many Gram-negative bacilli than currently used carbapenems, β-lactam/β-lactamase inhibitor combinations, and cephalosporins. Thus, we investigated the in vitro activity of cefiderocol against a total of 246 clinical isolates of Burkholderia pseudomallei from Queensland, Australia. The collection was composed primarily of bloodstream (56.1%), skin and soft tissue (16.3%), and respiratory (15.9%) isolates. MICs of cefiderocol ranged from ≤0.03 to 16 mg/liter, whereas the MIC90 was 0.125 mg/liter. Based upon CLSI clinical breakpoints for cefiderocol against Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia, three isolates (1.2%) would be classified as nonsusceptible (MIC > 4 mg/liter). Using EUCAST non-species-specific (pharmacokinetic/pharmacodynamic [PK/PD]) clinical breakpoints or those set for Pseudomonas aeruginosa, four isolates (1.6%) would be resistant (MIC > 2 mg/liter). Further testing for coresistance to meropenem, ceftazidime, trimethoprim-sulfamethoxazole, amoxicillin-clavulanate, and doxycycline was performed on the four isolates with elevated cefiderocol MICs (>2 mg/liter); all isolates exhibited resistance to amoxicillin-clavulanic acid, while three isolates also displayed resistance to at least one other antimicrobial. Cefiderocol was found to be highly active in vitro against B. pseudomallei primary clinical isolates. This compound shows great potential for the treatment of melioidosis in countries of endemicity and should be explored further.

Genotype-free demultiplexing of pooled single-cell RNA-seq

A variety of methods have been developed to demultiplex pooled samples in a single cell RNA sequencing (scRNA-seq) experiment which either require hashtag barcodes or sample genotypes prior to pooling. We introduce scSplit which utilizes genetic differences inferred from scRNA-seq data alone to demultiplex pooled samples. scSplit also enables mapping clusters to original samples. Using simulated, merged, and pooled multi-individual datasets, we show that scSplit prediction is highly concordant with demuxlet predictions and is highly consistent with the known truth in cell-hashing dataset. scSplit is ideally suited to samples without external genotype information and is available at: https://github.com/jon-xu/scSplit.

Health and happiness is more important than weight': a qualitative investigation of the views of parents receiving written feedback on their child's weight as part of the National Child Measurement Programme

BACKGROUND

The present study aimed to explore parental perceptions of overweight children and associated health risks after receiving National Child Measurement Programme (NCMP) weight feedback.

METHODS

Fifty-two parents of overweight and obese children aged 4-5 years and 10-11 years enrolled in the NCMP programme in England in 2010-2011 participated in qualitative, semi-structured interviews about their perceptions of their child's weight and health risk after receiving weight feedback. Interviews were audio tape recorded and were conducted either by telephone (n = 9) or in the respondents' homes (n = 41). Interviews were transcribed verbatim and analysed using interpretative thematic analysis.

RESULTS

Parents who received NCMP written feedback informing them that their child was overweight disregarded the results because they viewed 'health and happiness as being more important than weight'. The feedback was viewed as less credible because it did not consider the individual child's lifestyle.'Broad definitions of healthy' were described that did not include weight,such as reference to the child having good emotional and physical health and a healthy diet. Parents attributed weight to 'inherited/acquired factors' such as genetics or puppy fat, or did not regard their child's 'appearance' as reflecting being overweight. 'Cultural influence' also meant that being overweight was not viewed negatively by some non-white parents.

CONCLUSIONS

After receiving written weight feedback, parents use methods other than actual weight when evaluating their child's weight status and health risks. Parents' conceptions of health and weight should be considered when communicating with parents, with the aim of bridging the gap between parental recognition of being overweight and subsequent behaviour change.

Seventeen years' follow-up of the tension-free vaginal tape procedure for female stress urinary incontinence

INTRODUCTION AND HYPOTHESIS

The minimally invasive tension-free vaginal tape (TVT) operation has become the "gold standard" of incontinence surgery. The aim of the present study was to evaluate the long-term effect of the tape material and to assess the continence status 17 years after surgery

METHODS

A cohort of 90 women operated upon with the TVT procedure at three Nordic centers has been prospectively followed for 17 years. All of the women alive according to national registries were contacted and invited to visit the clinics for evaluation. Pelvic examination was performed to reveal any adverse effects of the tape material. Objective and subjective continence status were assessed by a cough stress test and the patients' global impression of improvement as well as by condition-specific quality of life questionnaires.

RESULTS

Seventy-eight percent of the potentially assessable women were evaluated either by a clinic visit or by a telephone interview. One case of a minimal, symptom-free tape extrusion was seen. No other tape complications occurred. Over 90 % of the women were objectively continent. Eighty-seven per cent were subjectively cured or significantly improved.

CONCLUSION

The TVT operation is durable for 17 years, with a high satisfaction rate and no serious long-term tape-induced adverse effects.

The impact of childhood obesity on morbidity and mortality in adulthood: a systematic review

The objective of this study was to evaluate the evidence on whether childhood obesity is a risk factor for adult disease, independent of adult body mass index (BMI). Ovid MEDLINE (1948-May 2011), EMBASE (1980-2011 week 18) and the Cochrane Library (1990-2011) were searched for published studies of BMI from directly measured weight and height in childhood (2-19 years) and disease outcomes in adulthood. Data were synthesized in a narrative fashion. Thirty-nine studies (n 181-1.1 million) were included in the review. There was evidence for associations between childhood BMI and type 2 diabetes, hypertension and coronary heart disease. Few studies examined associations independent of adult BMI; these showed that effect sizes were attenuated after adjustment for adult BMI in standard regression analyses. Although there is a consistent body of evidence for associations between childhood BMI and cardiovascular outcomes, there is a lack of evidence for effects independent of adult BMI. Studies have attempted to examine independent effects using standard adjustment for adult BMI, which is subject to over-adjustment and problems with interpretation. Studies that use more robust designs and analytical techniques are needed to establish whether childhood obesity is an independent risk factor for adult disease.

Eleven years prospective follow-up of the tension-free vaginal tape procedure for treatment of stress urinary incontinence

The aim of this study was to evaluate the long-term effectiveness and safety of the tension-free vaginal tape (TVT) procedure. In a Nordic three-center prospective observational cohort study, 90 women with primary stress incontinence had a TVT operation performed in local anesthesia. Assessment included a 24-h pad test, a stress test, physical examination, and a visual analog scale for assessing the degree of bother. Patient's global impression of cure was obtained, and condition specific quality of life questionnaires were used. Seventy-seven percent of the initial cohort of 90 women and 89% of those alive and capable of cooperating were assessed 11.5 years after the TVT operation. Ninety percent of the women had both a negative stress test and a negative pad test being objectively cured. Subjective cure by patients global impression was found in 77%, 20% being improved and only 3% regarded the operation as a failure. No late-onset adverse effects of the operation were found, and no case of tape erosion was seen. The TVT procedure is safe and effective for more than 10 years.

Sexual function in obese women: impact of lower urinary tract dysfunction

OBJECTIVE

To assess the impact on sexual function attributed to lower urinary tract dysfunction in a female obese population.

DESIGN

We performed a case-control study based on the registry of a university hospital obesity unit. A consecutive sample of women with body mass index(BMI) >or=30 (obese) was randomly matched by age, gender and residential county to control subjects using the computerized Register of the Total Population. Data were collected by a self-reported postal survey including the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12).

RESULTS

The questionnaire was completed and returned by 279/446 patients (62%) and 430/892 control subjects (48%). Obese women reported significantly lesser satisfaction with their sexual life, more frequent symptoms of urinary incontinence at intercourse, more often fear of urine leakage at intercourse, a higher tendency toward avoiding intercourse and more frequent feelings of guilt and disgust during intercourse (P<0.001). While considering sexual function in a subset of women with urge or stress urinary incontinence, the overall PISQ-12 scores were significantly lower in obese women compared to their age-matched nonobese controls for both the conditions (P<0.001). In an adjusted multivariate analysis, a BMI >30 was independently associated with a significantly increased risk for sexual dysfunction (odds ratio (OR) 1.8; 95% confidence interval (CI) 1.1-2.9), as were symptoms of urge or stress urinary incontinence (OR, 2.0; 95% CI, 1.3-3.1 and OR, 2.6; 95% CI, 1.7-4.0), respectively.

CONCLUSION

Urge and stress urinary incontinences are more common and have greater impact on sexual function in obese women.

Expression of the vascular endothelial growth factor (VEGF) family in human endometrial blood vessels

Endometrial regrowth is associated with intense angiogenesis, for which vascular endothelial growth factor-A (VEGF-A) is an important regulator. However, the expression of other members of the VEGF family is less well documented. The aim of this study was to localize members of the VEGF family (VEGF-A, -B and -C), and their receptors (VEGFR1, 2 and 3) in human endometrial blood vessels. Endometrial biopsies collected from four healthy and fertile women were used for immunohistochemistry assessments. Co-localization of VEGF-family proteins with CD34 stained endothelial structures was determined by image analysis. We demonstrate here the marked expression of VEGF-A as well as VEGFR2 and 3 in capillaries. Arterioles expressed VEGF-B, VEGFR1, 2, and 3 moderately and VEGF-A variably. Venules expressed only VEGFR3 markedly. In contrast, VEGF-C was not expressed in the arterioles, but moderately in the capillaries and weakly in the venules. VEGF-B was expressed in all blood vessels; however, VEGF-B was weakly expressed in capillaries and arterioles and moderately expressed in venules and arterioles. Thus, expression of VEGF-A. B and C and VEGF receptors 1-3 in endometrial blood vessels indicates a highly structured involvement of VEGF in the regulation of angiogenesis in the human endometrium.

Long-term results of the tension-free vaginal tape (TVT) procedure for surgical treatment of female stress urinary incontinence

In a prospective long-term Nordic multicenter study, 90 consecutive patients who had a tension-free vaginal tape (TVT) operation performed because of stress urinary incontinence were evaluated according to a strict protocol after approximately 5 years (range 48-70 months). Eighty-five patients could be evaluated according to the protocol. Another 5 elderly patients had to be interviewed by telephone at the final check-up after 5 years. The study protocol involved pre- and postoperative objective and subjective evaluation. The median follow-up time was 56 months. Seventy-two of the 85 patients who were fully evaluated (84.7%) were both objectively and subjectively completely cured. Another 9 patients (10.6%) were significantly improved and 4 (4.7%) were regarded as failures. No patient complained of long-term voiding difficulties and there were no signs of defective healing or rejection of the tape material. All patients had suffered from primary stress incontinence, and 25 also had preoperative complaints of urge. In 14 of these (56%) the urge symptoms were relieved postoperatively. We conclude that the TVT procedure seems to fulfil the expectations of high long-term cure rates, as suggested in previous short-term reports.

Tension-Free vaginal tape (TVT) in stress incontinent women with intrinsic sphincter deficiency (ISD)--a long-term follow-up

In a prospective long-term study 49 women with stress incontinence and ISD (intrinsic sphincter deficiency) were followed for a mean of 4 years (range 3-5) after TVT operation. Preoperatively all patients underwent urodynamic investigations, quality of life evaluation, a 24-hour pad test and a gynecologic examination to properly verify the incontinence symptoms. The same protocol was used for postoperative evaluation. The mean age of the women was 66 years (+/- 11) and mean parity 2 (range 0-4). A standard TVT operation was performed under local anesthesia. At the postoperative evaluations 36 patients (74%) were completely cured of their incontinence problems. In addition, 6 women (12%) were significantly improved. In 7 patients (14%) no improvement was found. The majority of these not cured patients were >70 years of age and had urethral resting pressure of <10 cmH2O. Few intra- and postoperative complications occurred. It is concluded that TVT can be used for surgical treatment of patients with ISD and stress incontinence. However, older patients (>70 years) with a very low resting urethral pressure and an immobile urethra seem to constitute a risk group where TVT surgery is less successful.

Influence of different sling materials on connective tissue metabolism in stress urinary incontinent women

The aim of this study was to investigate the influence on the paraurethral connective tissue of different sling materials used in incontinence surgery. Biopsies from the paraurethral connective tissue were obtained intraoperatively from 16 women with stress urinary incontinence; all were operated on with the TVT procedure, 6 with Mersilene as the sling material and 10 with Prolene. Biopsies from 4 continent women with uterine bleeding irregularities, matched for age and parity, served as controls. New biopsies were obtained from all women after 2 years. The biopsies were examined histologically and analyzed for collagen concentration and solubility. An obvious inflammatory reaction with a significant increase in collagen extractability by pepsin was identified in patients where Mersilene was used as the sling material. A minimal inflammatory reaction without a significant change in collagen solubility was found in the Prolene group. In the control group no inflammatory reaction was seen. Mersilene gave rise to a significant foreign-body reaction in the paraurethral connective tissue after surgery. Such a reaction was not found with Prolene.

Increased blood flow and erythema in the posterior vestibular mucosa in vulvar vestibulitis(1)

OBJECTIVE

To evaluate vascular changes as a possible underlying cause of mucosal erythema in women with vulvar vestibulitis.

METHODS

Laser Doppler perfusion imaging was used to map the superficial blood flow in the vestibular mucosa in 20 women with vestibulitis and in 21 healthy control subjects. A possible correlation between perfusion values and graded erythema (1-5) around the vaginal introitus was analyzed. Changes in microvascular density in the posterior part of the mucosa were investigated in sections from ten patients and ten controls by a computer-assisted image-processing program. Induced vasoconstriction of terminal arterioles in the same posterior area was also studied.

RESULTS

Significant increases in perfusion values were registered in the posterior parts of the vestibular mucosa in patients compared with controls. The highest blood flow was registered in the posterior fourchette. The most pronounced erythema was also located in the posterior vestibule in the patients. However, there was no significant correlation between perfusion values and degree of erythema in the same individual. The microvascular density or the ability of vestibular arterioles to constrict did not differ between patients and controls.

CONCLUSION

Women with vestibulitis have an increased superficial blood flow and erythema in the posterior parts of the vestibular mucosa. The increased perfusion, most probably caused by a neurogenic vasodilatation contributes to, but does not fully explain the erythema. Atrophic changes of the surface epithelium should also be considered in the evaluation of an erythema.

The expression of cyclooxygenase 2 and inducible nitric oxide synthase indicates no active inflammation in vulvar vestibulitis

BACKGROUND

Although women with vulvar vestibulitis syndrome have principal symptoms of inflammation such as local erythema and pain in the mucosa around the vaginal introitus, it is not clear if vestibulitis is an inflammatory condition. Cyclooxygenase 2 and inducible nitric oxide synthase are known to be upregulated during inflammation. The aim of the present study was to analyze the expression of these enzymes in the vestibular mucosa in order to evaluate the inflammatory activity in the tissue.

METHODS

Ten women fulfilling Friedrich's criteria of vulvar vestibulitis syndrome and ten control subjects were included in the study. Punch biopsies were obtained from the vestibular mucosa for analysis of cyclooxygenas 2 and inducible nitric oxide synthase, using indirect immunohistochemistry and Western dot-blot analyses.

RESULTS

Both methods used showed low expression of cyclooxygenas 2 and inducible nitric oxide synthase in the vestibular mucosa of all women. There was no difference observed between the groups.

CONCLUSIONS

There is a low expression of the inflammatory markers cyclooxygenas 2 and inducible nitric oxide synthase in the vestibular mucosa of women with vulvar vestibulitis syndrome as well as in healthy control subjects. The results indicate no active inflammation present and imply that topical corticosteroids in the treatment of vulvar vestibulitis are unfounded.

The safety and efficacy of MenoTreat, a new balloon device for thermal endometrial ablation

BACKGROUND

An evaluation of the performance and safety of the prototype of a new device, MemoTreat (Atos Medical) for thermal endometrial balloon ablation in patients with menorrhagia. The evaluation was performed at four Swedish hospitals.

METHODS

In total 51 consecutive, premenopausal patients, suffering from menorrhagia due to benign causes and not responding to conventional treatment, were treated between March 1997 and March 1998. The treatment entailed heated (85 degrees C) sterile saline circulated in a uterine balloon at a treatment pressure of 200 mmHg for 11 minutes. The procedure was performed mainly under general anesthesia and no pre-treatment endometrial thinning was performed. A validated pictorial assessment technique was used to evaluate changes in menstrual blood loss before and after treatment. Changes in quality of life and severity of dysmenorrhea were also evaluated. Data analysis was based on the 'intention to treat' method.

RESULTS

The success rate in terms of a 50% reduction in menstrual bleeding was 84.3% at 6 months after treatment. Five patients became amenorrheic. The quality of life assessment showed substantial improvement and the severity of dysmenorrhea was markedly reduced. No intra-operative treatment complications occurred and the post-treatment morbidity was similar to that reported for other similar treatment methods.

CONCLUSIONS

MenoTreat significantly reduced menstrual bleeding in menorrhagic patients, with a concomitant improvement in quality of life. The findings in this study resulted in a redesigned device with a thinner balloon catheter, improved cervical protection and treatment temperatures kept at a constant level.

The Pseudomonas aeruginosa lectins PA-IL and PA-IIL are controlled by quorum sensing and by RpoS

In Pseudomonas aeruginosa, many exoproduct virulence determinants are regulated via a hierarchical quorum-sensing cascade involving the transcriptional regulators LasR and RhlR and their cognate activators, N-(3-oxododecanoyl)-L-homoserine lactone (3O-C12-HSL) and N-butanoyl-L-homoserine lactone (C4-HSL). In this paper, we demonstrate that the cytotoxic lectins PA-IL and PA-IIL are regulated via quorum sensing. Using immunoblot analysis, the production of both lectins was found to be directly dependent on the rhl locus while, in a lasR mutant, the onset of lectin synthesis was delayed but not abolished. The PA-IL structural gene, lecA, was cloned and sequenced. Transcript analysis indicated a monocistronic organization with a transcriptional start site 70 bp upstream of the lecA translational start codon. A lux box-type element together with RpoS (sigma(S)) consensus sequences was identified upstream of the putative promoter region. In Escherichia coli, expression of a lecA::lux reporter fusion was activated by RhlR/C4-HSL, but not by LasR/3O-C12-HSL, confirming direct regulation by RhlR/C4-HSL. Similarly, in P. aeruginosa PAO1, the expression of a chromosomal lecA::lux fusion was enhanced but not advanced by the addition of exogenous C4-HSL but not 3O-C12-HSL. Furthermore, mutation of rpoS abolished lectin synthesis in P. aeruginosa, demonstrating that both RpoS and RhlR/C4-HSL are required. Although the C4-HSL-dependent expression of the lecA::lux reporter in E. coli could be inhibited by the presence of 3O-C12-HSL, this did not occur in P. aeruginosa. This suggests that, in the homologous genetic background, 3O-C12-HSL does not function as a posttranslational regulator of the RhlR/C4-HSL-dependent activation of lecA expression.

Increased intraepithelial innervation in women with vulvar vestibulitis syndrome

Women with vulvar vestibulitis syndrome (VVS) suffer from severe pain and discomfort in the area around the introitus at almost any stimulus that causes pressure within the vestibule. In spite of the severe sensory symptoms present in these women, the influence of the peripheral nerves in the vulvar vestibulum has not been clarified before. In this study the nerve supply in the vestibular mucosa in women with VVS and in healthy women free from vulvar symptoms has been revealed by PGP 9.5 immunohistochemistry. The results show a significant increase in the number of intraepithelial nerve endings in women with VVS, indicating an alteration in the nerve supply in the afflicted area.

Neurochemical characterization of the vestibular nerves in women with vulvar vestibulitis syndrome

Women with vulvar vestibulitis syndrome (VVS) have a distinct burning pain provoked by almost any stimuli in the area around the vaginal introitus. In a previous study we observed an increased number of intraepithelial free nerve endings in women with VVS. The aim of the present study was to neurochemically characterize the superficial nerves in the vulvar vestibular mucosa of women with VVS. Immunohistochemical methods were used to detect neuropeptides normally found in various types of nerve fibers. Calcitonin gene-related peptide, which is known to exist in nociceptive afferent nerves, was the only neuropeptide detected in the superficial nerves of the vestibular mucosa. These findings confirm our previous theory that the free nerve endings within the epithelium are nociceptors.

Connective tissue in female urinary incontinence

An effective closure of the female urethra in stress situations is dependent on an integrated action of various anatomical structures connected to the organ. The most important of these structures - from a functional aspect - are the suburethral vaginal wall, the pubourethral ligaments, the pubococcygeus muscles and the paraurethral connective tissues. In all these structures connective tissue is an essential ingredient. Hence, defects in the actual connective tissue - in particular the paraurethral connective tissue that connects the aforementioned structures to each other and to the urethra - will bring about an ineffective urethral closure. Female urinary incontinence may then be caused by defective connective tissue per se and/or by a disconnection of the aforementioned structures, whereby the urethra cannot be 'kinked' - that is, closed off in stress situations.

A multicenter study of tension-free vaginal tape (TVT) for surgical treatment of stress urinary incontinence

The aim of the study was to evaluate the safety and efficacy of TVT (tension-free vaginal tape) for the surgical treatment of stress urinary incontinence. The design was a prospective open multicenter study including six centers, each operating an approximately 20 patients. In total 131 patients suffering from genuine stress incontinence were included. They were followed for at least 1 year using a specific protocol for objective and subjective evaluation of the outcome. All patients underwent the operation under local anesthesia. Mean operation time was 28 minutes (range 19-41 minutes); 119 (91%) of the patients were cured according to the protocol and another 9 (7%) were significantly improved. There were 3 (2%) failures. The majority of the patients (about 90%) were operated upon on a day-care basis, which implied that they were released from the hospital within 24 hours, with no postoperative catheterization. No defect healing and no tape rejection occurred. Three patients needed an indwelling catheter for 3 days. In 1 patient catheterization was necessary for more than 10 days. Two uncomplicated hematomas and one uncomplicated bladder perforation occurred. Based on the results, we conclude that TVT is a safe and effective ambulatory procedure for surgical treatment of genuine stress urinary incontinence.

Streptomyces thermocarboxydovorans sp. nov. and Streptomyces thermocarboxydus sp. nov., two moderately thermophilic carboxydotrophic species from soil

Four moderately thermophilic, carboxydotrophic streptomycetes were the subject of a comparative taxonomic investigation designed to establish their taxonomic relationships. Almost complete sequences of the 16S rRNA genes of the test strains were determined following the isolation and direct sequencing of the amplified genes. The resultant nucleotide sequences were aligned with the sequences of previously studied streptomycetes, and phylogenetic trees generated by using the neighbour-joining, Fitch-Margoliash, maximum-likelihood and maximum-parsimony methods. It was evident from the phylogenetic analyses that strains AT50, AT51 and AT52 were most closely related to Streptomyces thermodiastaticus DSM 40573T and strain AT37 to Streptomyces glaucescens DSM 40716 and Streptomyces pseudogriseolus NRRL 3985. Random DNA amplification profiles clearly distinguished strains AT50, AT51 and AT52 from Streptomyces thermodiastaticus and from strain AT37. The molecular systematic evidence, together with phenotypic data derived from this and previous studies, indicate that the test strains merit species status within the genus Streptomyces. The name Streptomyces thermocarboxydovorans sp. nov. is proposed for strains AT50, AT51 and AT52 (type strain) and Streptomyces thermocarboxydus sp. nov. for strain AT37.

Different organization of collagen fibrils in stress-incontinent women of fertile age

OBJECTIVE

The objective was to test the hypothesis that stress urinary incontinence in women is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.

METHODS

Transvaginal biopsies were obtained from the paraurethral connective tissue in women of fertile age with stress urinary incontinence and in matched continent controls. All the stress-incontinent women were characterized with urodynamic investigation. In the biopsies, collagen concentration, measured as hydroxyproline, and the degree of extraction by pepsin digestion were quantified. Proteoglycan composition and concentration were analyzed using Alcian blue precipitation, followed by electrophoretic separation and quantification. Using Northern blots mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen organization was examined with transmission electron microscopy and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).

RESULTS

The biochemical and morphological analyses exposed a significant difference in the paraurethral connective tissue between stress urinary incontinent women before menopause and comparable controls. The collagen concentration was almost 30% higher and the diameters of the collagen fibrils were 30% larger in the incontinent group of women. Also the organization of the collagen fibrils differed, with considerably higher cross-linking. A higher level of mRNA for collagen I and III in the incontinent group indicates that the differences can be related to an altered collagen metabolism. No change of proteoglycan amount or composition was observed, resulting in a significantly lower proteoglycan/collagen ratio in the incontinent group of women.

CONCLUSION

Stress urinary incontinence in fertile women is associated with a change in collagen metabolism resulting in an increased concentration of collagen and larger collagen fibrils. These alterations should result in a more rigid form of extracellular matrix, suggesting a connective tissue with impaired mechanical function.

Paraurethral connective tissue in stress-incontinent women after menopause

OBJECTIVE

To study whether stress urinary incontinence after menopause is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.

METHODS

Transvaginal biopsies were obtained from the paraurethral connective tissue in stress urinary incontinent women after menopause with and without estrogen replacement therapy, and from comparable controls. All the stress-incontinent women underwent urodynamic investigation. In the specimens, collagen concentration, measured as hydroxyproline, and the degree of extractability by pepsin digestion, were quantified. Proteoglycan composition and concentration were analyzed using Alcian Blue precipitation, followed by electro-phoretic separation and quantification. Using Northern blots, mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen structure was examined with transmission electron microscopy, and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).

RESULTS

No significant difference in paraurethral connective tissue biochemistry or ultrastructure was registered between women with stress incontinence and controls. Estrogen replacement therapy resulted in a lower collagen concentration both between the controls (p = 0.02) and between the incontinent women (0.02). In the women with stress incontinence also the extractability by pepsin digestion was higher in the group with estrogen treatment (p = 0.004), indicating a decrease in cross-linking. The proteoglycan/collagen ratio was higher in the control group with estrogen treatment compared to untreated (p = 0.02), but no difference was found between estrogen treated and untreated incontinent women. The median collagen fibril diameter was 15% larger in the incontinent group of women without estrogen therapy compared to the control group and 5% larger when comparing the incontinent group on estrogen replacement therapy to the corresponding control group.

CONCLUSION

The extracellular matrix of paraurethral connective tissue in stress urinary incontinent women after menopause reacted differently to estrogen replacement therapy compared to continent controls. In contrast to incontinent women of fertile age no major changes in collagen metabolism were found in stress urinary incontinent women after menopause.

Decreased innervation of the paraurethral epithelium in stress urinary incontinent women

OBJECTIVE

To determine whether there is a difference in the innervation of the paraurethral vaginal epithelium between stress urinary incontinent women of fertile age and comparable controls.

METHODS

Transvaginal biopsies close to the external orifice of the urethra were obtained from 11 stress urinary incontinent women and from ten comparable controls. The specimens were processed for indirect immunohistochemistry using protein gene product 9.5 (PGP 9.5) as a general neuronal marker. From each biopsy, ten randomly selected fields of 1 mm2 projected area were investigated and nerve fibre profiles were quantificated in a microscope equipped with light- and dark-field optics.

RESULTS

Nerve fibre profiles/mm2 of projected epithelial area were significantly lower in the incontinent group than in the control group (P < 0.01).

CONCLUSION

Our study indicates that stress urinary incontinent women have a significantly lower total innervation of the paraurethral vaginal epithelium than continent controls.

Changes in paraurethral connective tissue at menopause are counteracted by estrogen

OBJECTIVE

To study whether the transition to menopause is accompanied by changes in the paraurethral connective tissue and if these changes are modified by estrogen replacement therapy.

STUDY DESIGN

Biopsies were obtained from the paraurethral tissue from 34 women; 12 menstruating, 14 postmenopausal without estrogen treatment, and 8 with estrogen treatment. Collagen concentration and collagen extractability by pepsin digestion were measured. Proteoglycan composition and concentration were analysed using Alcian blue. The mRNA levels for collagen I and III, the small proteoglycans (PGS) decorin and biglycan, and the large proteoglycan versican, were estimated.

RESULTS

The paraurethral biopsies consisted of fibrous connective tissue, with collagen fibers as dominating structure. Several proteoglycans were identified; versican, heparansulphate proteoglycans, biglycan and decorin. The small proteoglycan decorin represented 85% of all proteoglycans. The collagen concentration was almost doubled in postmenopausal biopsies compared to premenopausal. The collagen fibril organization was also changed with higher cross-linking after menopause whereas the amount and the composition of the proteoglycans were unchanged. The proteoglycan/collagen ratio was significantly decreased. Estrogen replacement therapy resulted in decreased collagen concentration, decreased cross-linking of the collagen and reversal of the PGS/collagen ratio to almost premenopausal level. The therapy resulted in increased levels of mRNA for collagen I and III which suggests that the changes are due to an increased turnover.

CONCLUSION

The decrease in estrogen levels at menopause results in a connective tissue with different qualities after menopause. Estrogen replacement therapy tends to restore the metabolism of the genitourinary connective tissue to premenopausal conditions.

Clinical outcome and changes in connective tissue metabolism after intravaginal slingplasty in stress incontinent women

The intravaginal slingplasty procedure (IVS) was carried out on 75 patients with genuine stress urinary incontinence. The main aims of the operation are to create an artificial pubourethral ligament and to tighten the suburethral vaginal wall. An important ingredient in the supportive structures of the genitourinary region is fibrous connective tissue, consisting mainly of collagen. To analyse this component biopsies were obtained transvaginally, close to the position of the sling, both preoperatively and 2 years after surgery, from 6 patients. Collagen was analysed for concentration and extractability. Extractability by pepsin digestion was increased by 60% 2 years following surgery. Postoperative follow-up studies from 12 months to 3 years showed complete restoration of continence in 63 patients (84%) and considerable improvement in 4 others (5%). The 8 failures (9%) were all related to early rejection of the sling. The IVS procedure is an attractive surgical procedure as it necessitates minimum invasion and can be performed under local anesthesia, with a short hospital stay and sick-leave period. The enhanced collagen extractability indicates a changed metabolism, most likely induced by the implanted sling, resulting in a restoration of the elastic properties of the connective tissue.

New and simplified vaginal approach for correction of urinary stress incontinence in women

Twenty-four patients with urodynamically confirmed urinary stress incontinence were operated upon with a new and simplified vaginal approach. This new technique is a simplification of a previously described transabdominal surgical method, in which a two-component fibrin sealant (Tisseel) was used. The sealant resulted in an excess of fibrin, which induced fibrosis, securing the urethrovesical junction in an elevated position to the retropubic periosteum. In the present study, the sealant was deposited retropubically with a specially designed needle through the anterior vaginal wall. A great advantage with this procedure is that only local anesthesia is used and the patient can leave the outpatient clinic 1 hour after the operation. The minimum duration of the follow-up period was 18 months. The success rate was as high as 63%, and no side effects were observed.

Innervation of the human vaginal mucosa as revealed by PGP 9.5 immunohistochemistry

In order to obtain a description of the innervation of the vaginal wall we employed an antiserum against the general neuronal marker, protein gene product 9.5, on normal human vaginal mucosa. Specimens were taken from the anterior and posterior fornices, from the anterior vaginal wall at the bladder neck level and from the introitus vaginae region, and then processed for indirect immunohistochemistry. All regions studied revealed a profound innervation, although regional differences were noted. The more distal areas of the vaginal wall had more nerve fibers compared to the more proximal parts. Also, biopsies from the anterior wall generally were more densely innervated than the posterior wall. Some large nerve coils were observed in lamina propria of the anterior wall as well as gatherings of thick-walled medium-sized blood vessels. Free intraepithelial nerve endings were only detected in the introitus vaginae region. These fibers were very thin, always varicose and could be observed just a few cell layers from the surface. In this part of the vagina, protein gene product 9.5 antibodies also stained cells within the basal parts of the epithelium. These cells were also neurone-specific enolase positive and resembled, from a morphological point of view, Merkel cells.

Decreased collagen synthesis in stress-incontinent women

OBJECTIVE

To determine whether there is a difference in collagen metabolism between comparable urinary stress-incontinent and -continent women.

METHODS

Fibroblast cultures from skin biopsies were established from seven stress-incontinent and four continent women. Collagen production was investigated in these cultures between passages 3 and 7 by incubation with 3H-proline, followed by quantitation of 3H-proline and 3H-hydroxyproline after hydrolysis of proteins and separation by high-pressure liquid chromatography. The chemical amount of collagen was also quantitated using Sircol Red.

RESULTS

Fibroblast cultures established from urinary stress-incontinent women accumulated 30% less collagen than comparable cultures from continent women. The differences were statistically significant (cell layer P = .038, medium P = .004; Student t test). These results were observed both when collagen concentration was measured with chemical methods and when the production of protein-bound 3H-hydroxyproline was quantitated. General protein synthesis was similar in the two groups.

CONCLUSION

Our results suggest that women with urinary stress incontinence have an altered connective tissue metabolism causing decreased collagen production, which may result in insufficient support of the urogenital tract.

Biosystematics and diversity amongst novel carboxydotrophic actinomycetes

Fifty-four carboxydotrophic actinomycetes isolated from soils and composts were compared through 119 unit characters with representative mesophilic and thermophilic streptomycetes. The data were examined using the Jaccard, pattern and simple matching coefficients and clustering achieved using the unweighted pair group method with arithmetic averages algorithm. Acceptable cophenetic correlation and test error values allowed confidence to be placed in the resultant numerical taxonomies. The carboxydotrophic actinomycetes, which were distinct from cluster-groups corresponding to the mesophilic and thermophilic streptomycetes, formed two major cluster-groups the members of which were examined for the presence of diagnostic chemical markers. All but two of the carboxydotrophic actinomycetes had a profile of chemical properties consistent with their assignment to the genus Streptomyces. Quantitative fatty acid data were examined using the SIMCA package and the two statistically significant groups obtained corresponded with the cluster-groups circumscribed in the numerical phenetic analysis. Members of the two groups were also distinguished on the basis of their phospholipid composition. The two strains that contained meso-as opposed to LL-diaminopimelic acid in their peptidoglycan also showed a distinct chemotaxonomic profile. It was concluded that the carboxydotrophic actinomycetes form a novel and taxonomically diverse group.

Sensory perception in the hands of dentists

The difference between the dominant and nondominant hands in the perception of vibration, temperature, and heat pain was compared between 26 dentists with long-term exposure to high-frequency vibration and 18 with short-term exposure. The dentists with long-term exposure had larger vibration threshold differences than those with short-term exposure, both for digit II (exposed to high-frequency vibration) and for digit V (unexposed), whereas the temperature and pain thresholds were similar. The former group had neurological symptoms in the dominant hand more often than the latter. Vibration threshold differences of exposed digit II and unexposed digit V were higher for the symptomatic dentists than for the symptom-free dentists. Since the exposed and unexposed fingers were similarly affected, the neurological symptoms in the dominant hand of dentists with long-term exposure seem to have some other etiology than high-frequency vibration.