Phase II clinical study of BC-3781, a pleuromutilin antibiotic, in treatment of patients with acute bacterial skin and skin structure infections

This study investigated the potential of the novel systemic pleuromutilin antibiotic BC-3781 to treat patients with an acute bacterial skin and skin structure infection (ABSSSI) caused by a Gram-positive pathogen. Patients were randomized to intravenous BC-3781 100 mg, BC-3781 150 mg, or vancomycin 1 g every 12 h. Response to treatment was assessed daily and at test of cure (TOC). The primary endpoint was the clinical success rate at TOC in the modified intent-to-treat (MITT) and clinically evaluable (CE) analysis populations. Baseline characteristics, including the frequency of methicillin-resistant Staphylococcus aureus (MRSA), were comparable between the different treatment groups. Of 210 patients randomized, 186 (88.6%) patients completed the study. Clinical success at TOC in the CE population occurred in 54 (90.0%) patients in the BC-3781 100-mg group, 48 (88.9%) in the BC-3781 150-mg group, and 47 (92.2%) in the vancomycin group. At day 3, the clinical response rate was similar across the three treatment groups. Six patients discontinued study medication following an adverse event. The incidence rate for drug-related adverse events was lower for patients receiving BC-3781 (34.3% and 39.4% in the 100-mg and 150-mg groups, respectively) than those receiving vancomycin (53.0%). When BC-3781 was used to treat ABSSSIs caused by a Gram-positive pathogen, including MRSA, clinical success rates were comparable to those of the comparator, vancomycin. BC-3781 was generally well tolerated. These results provide the first proof of concept for the systemic use of a pleuromutilin antibiotic for the treatment of ABSSSIs.

Genetic fate-mapping of tyrosine hydroxylase-expressing cells in the enteric nervous system

BACKGROUND

During development of the enteric nervous system, a subpopulation of enteric neuron precursors transiently expresses catecholaminergic properties. The progeny of these transiently catecholaminergic (TC) cells have not been fully characterized.

METHODS

We combined in vivo Cre-lox-based genetic fate-mapping with phenotypic analysis to fate-map enteric neuron subtypes arising from tyrosine hydroxylase (TH)-expressing cells.

KEY RESULTS

Less than 3% of the total (Hu(+) ) neurons in the myenteric plexus of the small intestine of adult mice are generated from transiently TH-expressing cells. Around 50% of the neurons generated from transiently TH-expressing cells are calbindin neurons, but their progeny also include calretinin, neurofilament-M, and serotonin neurons. However, only 30% of the serotonin neurons and small subpopulations (<10%) of the calbindin, calretinin, and neurofilament-M neurons are generated from TH-expressing cells; only 0.2% of nitric oxide synthase neurons arise from TH-expressing cells.

CONCLUSIONS & INFERENCES

Transiently, catecholaminergic cells give rise to subpopulations of multiple enteric neuron subtypes, but the majority of each of the neuron subtypes arises from non-TC cells.

Practice of dilatation after surgical correction in anorectal malformations

BACKGROUND

In order to prevent stricture of the neoanus after surgical correction, regular dilatation is recommended. There is a lack of knowledge about the performance of anal dilatation and the occurrence of pain. The aim of our investigation was to describe the practice of dilatation and to identify possible risk factors for painful procedures.

METHODS

Congenital Uro-Rectal Malformations Network is a German interdisciplinary multicenter research network. With standard questionnaires, physicians interviewed 243 patients and/or their parents at home, additional 103 patients born since 2009 were assessed through their treating physicians.

RESULTS

In total, 88 % of the patients received dilatations. Treatment lasted for 7 months in median (range 1-156 months), until the age of 13 months (range 1-171 months). In 69 % painful dilatation was reported; without a significant differences in age or gender. In 32 % bleeding was reported. In 30 % at least one dilatation was performed under general anesthesia. In 11 % some kind of analgesia was used. Type of fistula, dilatations lasting longer than 10 months and Hegar size above 15 were relevant factors for experience of pain. There were about 16 % postoperative strictures of the neoanus, without reported differences in dilatation procedures; but there was a relation to type of malformation.

CONCLUSION

Considering the high number of painful treatments, predictors for painful dilatations should be further clarified through standardized documentation and prospective evaluation in order to improve follow-up.

Outcome of augmentation cystoplasty and bladder substitution in a pediatric age group

OBJECTIVE

Aim of the study was to evaluate the outcome of augmentation cystoplasty and bladder substitution in a pediatric age group.

METHODS

Patient records of all children who underwent reconstructive bladder surgery between October 1999 and November 2007 were reviewed. Additionally, standardized interviews were performed to evaluate the postoperative outcome.

RESULTS

Augmentation cystoplasty and bladder substitution were performed in 19 and 6 patients, respectively. 21 patients underwent continent catheterizable vesicostomy. Postoperative urodynamics revealed a significant increase in bladder volume (median 400 ml) as well as a significant improvement in bladder compliance (median 13.5 ml/cmH2O). 90% of the patients were reported to be socially continent. Renal function remained stable in 95% and decreased in 5% of the children. Major complications were lower urinary tract calculi (39%), stricture or insufficiency of the continent vesicostomy (28%), and intestinal obstruction (9%). No malignancies associated to bladder augmentation or substitution were detected yet.

CONCLUSION

Augmentation cystoplasty and bladder substitution preserve renal function and provide urinary continence in most children with intractable lower urinary tract disease. However, the procedures remain associated with numerous complications.

[Functional outcome in children with Hirschsprung's disease or imperforate anus]

Various outcomes following operative therapy for Hirschsprung's disease and anorectal malformations have been reported. Operative techniques for anorectal reconstruction have been modified several times in the past. Repair of anorectal -malformations have been performed through a posterior sagittal approach since the 1980s. This -allows an anatomically correct reconstruction of the anorectal canal. Abdominoperineal or sacro-abdominoperineal pull-through procedures, as the classical operative techniques, have been abandoned by most surgeons. Rectosigmoid-ectomy with colo-anal anastomosis, as described by Swenson and Bill in 1948, as well as the retro-rectal pull-through (Duhamel) and the endorectal pull-through (Soave) are still frequently used in surgery for Hirschsprung's disease. The development of the transanal endorectal pull-through with (Georgeson) or without (de la Torre) laparoscopic assistance has eliminated the necessity of laparotomy in selected cases. Despite significant progress in the understanding of the pathophysiology of and therapy for Hirschsprung's dis-ease and anorectal malformations, the functional results remain unsatisfactory. Functional problems occur already in early childhood and de-crease the quality of life significantly. Although complications resolve with time and the quality of life normalises in adolescence and adulthood, this might be mainly due to an adaptation strategy by the patients. For the future, a standardised and prospective study design is necessary to compare different procedures and to provide a basis for the further development of therapeutic strategies.

Outcome of transanal endorectal pull-through in patients with Hirschsprung's disease

INTRODUCTION

Various outcomes following transanal endorectal pull-through (TERPT) in patients with Hirschsprung's disease (HD) have been reported. In this study, the postoperative course and functional outcome after TERPT in 25 patients with HD is evaluated.

METHODS

Patient records of children who underwent TERPT for HD between 2002 and 2007 were reviewed retrospectively. Age at surgery, sex, associated malformations, length of follow-up, presence of colostomy, indication for laparotomy, length of the aganglionic segment, result of rectal examination under general anaesthesia 6 weeks after surgery, necessity of a dilatation program or reoperation were investigated. In addition, standardised interviews were performed to collect the following data: bowel movement per day, faecal continence in potty-trained children or in patients older than 3 years, incidence of diarrhoea or problems with micturition and the necessity for laxative therapy.

RESULTS

Between 2002 and 2007, 25 patients underwent TERPT for HD. Median age at the time of surgery was 3.5 months. Median follow-up was 35 months. Calibration of the anus showed a normal age-related diameter of the anus in 12/20 children and a markedly reduced diameter in 8/20 children at 6 weeks postoperatively. Seven of the latter children underwent a dilatation program. A redo pull-through procedure was performed in 3 patients due to stenosis at the colo-anal anastomosis (n=1), a constricting muscle cuff (n=1) and a twisted pull-through (n=1). Two children developed enterocolitis. The median frequency of bowel movements was 3/day (1-5/day). Laxative treatment was required in only one patient (4.5%). None of the patients had diarrhoea. Nineteen children (86%) were potty-trained, being older than 3 years. Eighteen of them were continent (95%). One patient (5%) with trisomy 21 suffered from intermittent non-retentive faecal incontinence. None of the patients showed signs of neurogenic bladder dysfunction.

CONCLUSION

The functional outcome in most patients after TERPT is satisfactory. We suggest that routine rectal digital examination and anal calibration under anaesthesia 6 weeks postoperatively might detect occult anodermal stenosis and allow early initiation of an anorectal dilatation program, which could decrease the incidence of enterocolitis, persistent constipation and the necessity for further surgical intervention.

Dynamische Magnetresonanz-Nephrografie und -Urografie bei Kindern mit Harnwegserkrankungen

PURPOSE

To evaluate an improved method of dynamic magnetic resonance (MR) nephrography with short acquisition time and compensation of breathing motion for assessment of renal excretion and split renal function in children with anomalies of the urinary tract.

MATERIALS AND METHODS

A protocol for dynamic MR nephrography was implemented using a T1-weighted navigator-gated TurboFLASH sequence (TR/TE 498 ms/1.25 ms, saturation recovery time 300 ms, flip angle 8 degrees ). After bolus injection of 0.05 mmol/kg gadolinium dimeglumine (Gd-DTPA), split renal function was determined from the contrast-medium excretion. In 20 patients (ages between 3 months and 14 years), dynamic MR nephrography and MAG3 radionuclide scintigraphy as the gold standard were performed.

RESULTS

In all children, T1-weighted images were able to be recorded over 40 minutes at a nearly identical diaphragm position using the TurboFLASH sequence, thus allowing for exact region-of-interest analysis of the excretion and split renal function. The course of the contrast-medium concentration was able to be measured in the renal pelvis with good accuracy due to the high spatial resolution and the lack of breathing artifacts. Excellent correlation to the MAG3 scintigraphy was demonstrated for the excretion and split renal function (correlation coefficient: 0.975).

CONCLUSION

Dynamic MR nephrography allows for reliable assessment of renal function in children with anomalies of the urinary tract with higher spatial resolution as compared to radionuclide scintigraphy.

Satraplatin, an oral platinum analog, is active and synergistic with paclitaxel and docetaxel in prostate carcinoma models

14620

Background: Satraplatin is a novel oral platinum analog with potent cytotoxic and antitumor activity in preclinical models. Satraplatin showed activity in hormone refractory prostate cancer (HRPC) and other tumor types in Phase II trials. A pivotal Phase III trial evaluating satraplatin as 2nd-line therapy for HRPC completed accrual of > 900 patients in 2005. Satraplatin’s activity, safety profile and ease of administration make it attractive for combination regimens. Methods: Satraplatin and its active metabolite JM-118 were tested in vitro as single agents in the androgen-sensitive LNCaP and the androgen-insensitive PC-3 and DU-145 human prostate carcinoma (ca.) cell lines. For in vitro combination studies, PC-3 cells were treated with satraplatin or JM-118 either prior to, after, or concomitantly with paclitaxel or docetaxel. The PC-3 cell line was used for in vivo xenograft experiments in nude mice. Paclitaxel was given intravenously on Day 1, satraplatin orally on Days 2 to 6, and paclitaxel again on Day 8. Results: Satraplatin and JM-118 as single agents inhibited the growth of all three prostate ca. cell lines in vitro in a dose dependent fashion. IC50 values for JM-118 were < 1μM. Strong synergism was noted when PC-3 tumor cells were treated in vitro with paclitaxel or docetaxel followed by satraplatin or JM-118. Satraplatin administered orally inhibited the growth of PC-3 xenografts in nude mice. Treatment of advanced PC-3 tumors with paclitaxel (40 mg/kg) and satraplatin (35 mg/kg) was well tolerated and resulted in a Tumor Growth Delay equivalent to 3 Log Cell Kill, an effect superior to that of the single agents. Conclusions: In vitro, satraplatin and its metabolite JM-118 are active as single agents against human prostate ca. cells, and are synergistic with taxanes. In vivo, treatment with paclitaxel followed by satraplatin showed synergism without increased toxicity. These preclinical data support ongoing Phase I and II clinical trials that are evaluating combinations of satraplatin with paclitaxel or docetaxel.

[Table: see text]

YKL-39 (chitinase 3-like protein 2), but not YKL-40 (chitinase 3-like protein 1), is up regulated in osteoarthritic chondrocytes

OBJECTIVE

To investigate quantitatively the mRNA expression levels of YKL-40, an established marker of rheumatoid and osteoarthritic cartilage degeneration in synovial fluid and serum, and a closely related molecule YKL-39, in articular chondrocytes.

METHODS

cDNA array and online quantitative polymerase chain reaction (PCR) were used to measure mRNA expression levels of YKL-39 and YKL-40 in chondrocytes in normal, early degenerative, and late stage osteoarthritic cartilage samples.

RESULTS

Expression analysis showed high levels of both proteins in normal articular chondrocytes, with lower levels of YKL-39 than YKL-40. Whereas YKL-40 was significantly down regulated in late stage osteoarthritic chondrocytes, YKL-39 was significantly up regulated. In vitro both YKLs were down regulated by interleukin 1beta.

CONCLUSIONS

The up regulation of YKL-39 in osteoarthritic cartilage suggests that YKL-39 may be a more accurate marker of chondrocyte activation than YKL-40, although it has yet to be established as a suitable marker in synovial fluid and serum. The decreased expression of YKL-40 by osteoarthritic chondrocytes is surprising as increased levels have been reported in rheumatoid and osteoarthritic synovial fluid, where it may derive from activated synovial cells or osteophytic tissue or by increased matrix destruction in the osteoarthritic joint. YKL-39 and YKL-40 are potentially interesting marker molecules for arthritic joint disease because they are abundantly expressed by both normal and osteoarthritic chondrocytes.

Large-scale screen for genes controlling mammalian embryogenesis, using high-throughput gene expression analysis in mouse embryos

We have adapted the whole-mount in situ hybridization technique to perform high-throughput gene expression analysis in mouse embryos. A large-scale screen for genes showing specific expression patterns in the mid-gestation embryo was carried out, and a large number of genes controlling development were isolated. From 35760 clones of a 9.5 d.p.c. cDNA library, a total of 5348 cDNAs, enriched for rare transcripts, were selected and analyzed by whole-mount in situ hybridization. Four hundred and twenty-eight clones revealed specific expression patterns in the 9.5 d.p.c. embryo. Of 361 tag-sequenced clones, 198 (55%) represent 154 known mouse genes. Thirty-nine (25%) of the known genes are involved in transcriptional regulation and 33 (21%) in inter- or intracellular signaling. A large number of these genes have been shown to play an important role in embryogenesis. Furthermore, 24 (16%) of the known genes are implicated in human disorders and three others altered in classical mouse mutations. Similar proportions of regulators of embryonic development and candidates for human disorders or mouse mutations are expected among the 163 new mouse genes isolated. Thus, high-throughput gene expression analysis is suitable for isolating regulators of embryonic development on a large-scale, and in the long term, for determining the molecular anatomy of the mouse embryo. This knowledge will provide a basis for the systematic investigation of pattern formation, tissue differentiation and organogenesis in mammals.

Gorlin syndrome: identification of 4 novel germ-line mutations of the human patched (PTCH) gene. Mutations in brief no. 137. Online

PTCH, the human homologue of the Drosophila segment polarity gene, patched, has been identified as the gene responsible for Gorlin or nevoid basal cell carcinoma syndrome (NBCCS). We report here the characterization of four novel mutations in the human PTCH gene in germ-line DNA from Gorlin patients. All mutations lead to truncation of the predicted protein product. Also included is a list of putative polymorphic nucleotide postions in the sequence covered by published primers.

The NH2 terminus of titin spans the Z-disc: its interaction with a novel 19-kD ligand (T-cap) is required for sarcomeric integrity

Titin is a giant elastic protein in vertebrate striated muscles with an unprecedented molecular mass of 3-4 megadaltons. Single molecules of titin extend from the Z-line to the M-line. Here, we define the molecular layout of titin within the Z-line; the most NH2-terminal 30 kD of titin is located at the periphery of the Z-line at the border of the adjacent sarcomere, whereas the subsequent 60 kD of titin spans the entire width of the Z-line. In vitro binding studies reveal that mammalian titins have at least four potential binding sites for alpha-actinin within their Z-line spanning region. Titin filaments may specify Z-line width and internal structure by varying the length of their NH2-terminal overlap and number of alpha-actinin binding sites that serve to cross-link the titin and thin filaments. Furthermore, we demonstrate that the NH2-terminal titin Ig repeats Z1 and Z2 in the periphery of the Z-line bind to a novel 19-kD protein, referred to as titin-cap. Using dominant-negative approaches in cardiac myocytes, both the titin Z1-Z2 domains and titin-cap are shown to be required for the structural integrity of sarcomeres, suggesting that their interaction is critical in titin filament-regulated sarcomeric assembly.

The human homologue of the ninjurin gene maps to the candidate region of hereditary sensory neuropathy type I (HSNI)

The human ninjurin gene was isolated from a cDNA library enriched for transcripts from band 9q22. A 1.2-kb message was detected for ninjurin in all human tissues studied. The full-length sequence codes for a putative 152-amino-acid protein with 89% identity to the rat ninjurin protein. The mouse homologue was isolated and showed 98% amino acid identity to the rat protein. Mapping by FISH localized mouse ninjurin to mouse chromosome 13, a region that shows synteny with human chromosome 9q22. Genomic characterization of the human gene revealed four exons covering less than 10 kb. The map position of the human gene is between the genetic markers D9S196 and D9S197 on human chromosome band 9q22. This places the gene within the candidate regions for the degenerative neurological disorder hereditary sensory neuropathy type I and the cancer predisposition syndrome multiple self-healing squamous epitheliomata.

FKHL15, a new human member of the forkhead gene family located on chromosome 9q22

FKHL15 was isolated from a cDNA library enriched for transcripts from 9q22. Isolation and sequencing of a 3.5-kb cDNA clone identified a putative 376-amino-acid protein with greater than 80% homology over a 100-amino-acid stretch to the forkhead DNA-binding domain. The FKHL15 gene contains a region rich in alanine residues, frequently associated with transcriptional repression. The forkhead genes are believed to play important roles in development and differentiation in many different organisms and have also been implicated in the development of some tumors. The map position of FKHL15 on 9q22 places the gene within the candidate regions for the cancer predisposition syndrome multiple self-healing squamous epitheliomata and the degenerative neurological disorder hereditary sensory neuropathy type I. This is a region frequently lost in squamous cell cancer.

A high-resolution radiation hybrid map of the region surrounding the Gorlin syndrome gene

We have constructed a set of hybrid cell lines by irradiation of GM 64063 (human chromosome 9q only on hamster background) and fusion to hamster A23 Tk-, 109 independent lines were tested by PCR with 24 markers from chromosome 9q. The marker density is highest in the 9q22.3-q31 region containing the gene for Gorlin syndrome, a familial predisposition to basal cell carcinoma. The resolution of our map in this region is significantly higher than other published maps and will enable accurate placing of new markers and genes within the 9q22.3-q3.1 region. This is important since yeast artificial chromosomes from the region are likely to contain deletions.