Chlamydial cervical infection in jailed women

OBJECTIVES: The prevalence of Chlamydia trachomatis cervical infection in incarcerated adult women has not been reported. To develop a policy for testing and treatment, we determined the prevalence of and risk factors for chlamydial infection in women in a New York City jail. METHODS: Interviews and cervical cultures for C trachomatis were obtained from 101 consenting female inmates. RESULTS: Positive cultures for C trachomatis were found in 27% of the participants. Mucopurulent cervical discharge and education of 8 years or less were two independent risk factors for infection, but only 63% of the infected women had one or both of these factors. If pelvic tenderness were considered as a third factor, an additional 7% of the infected women would have been identified. CONCLUSIONS: The prevalence of chlamydial infection in this population was as high as that in populations for which presumptive treatment is recommended. Although the optimal policy for detection and treatment of chlamydial infection may vary depending on practical considerations, we suggest that women entering correctional facilities should be screened or offered presumptive therapy for C trachomatis infection.     

Badgers, bovine tuberculosis and the age of reason

To evaluate the transmission of genital human papillomavirus (HPV) through the floor and seats of humid dwellings, samples were collected with a toothbrush from the floor and seat surfaces of humid dwellings; showers, saunas and dressing rooms. The survey included 3 bathing resorts, 1 indoor swimming pool, 2 schools and 2 private homes. Polymerase chain reaction (PCR) was used to amplify the human beta-globin gene and HPV DNA. The results for HPV DNA amplification were confirmed by Southern blot hybridization under low stringency using a probe mixture of HPV types 6, 16, 18 and 31. beta-globin could be amplified only from 3 sample taken from a dressing room of and indoor public swimming pool. No HPV DNA-positive samples were found. These results indicate that transmission of genital HPV infection via floor or seat surfaces in the above dwellings in general or family use is highly unlikely.     

Use of a fluorescence spectroscopic readout to characterize the interactions of Cdc42Hs with its target/effector, mPAK-3

The family of p21-activated kinases (PAKs) has been shown to contain a domain that can independently bind to the Ras-like proteins Cdc42Hs and Rac. We have expressed a 72 amino acid recombinant form of this p21-binding domain (PBD) from mPAK-3 in Escherichia Coli for use in structure-function studies. The protein can be purified on a nickel affinity resin due to a hexa-His tag that is incorporated onto the amino terminus of the domain. PBD binds to Cdc42Hs in a guanine nucleotide-dependent manner as demonstrated by a novel fluorescence assay that takes advantage of the spectroscopic properties of N-methylanthraniloyl (Mant)-guanine nucleotides. Ionic strength has little effect on the affinity of PBD for Cdc42Hs, but alkaline pH values tend to weaken the interaction. We have shown that the inhibition of the GTPase activity of Cdc42Hs, as well as a previously undescribed inhibition of guanine nucleotide dissociation, is mediated by the PBD portion of the mPAK-3 molecule. These findings suggest that PBD binding alters the geometry of the guanine nucleotide binding site on Cdc42Hs, perhaps as an outcome of the target/effector molecule binding in close proximity to the nucleotide domain. We therefore tested if mutations in the effector region of Cdc42Hs (32-40), which in Ras are very close to the guanine nucleotide binding site, had any effect on PBD binding. Changing tyrosine 32 to lysine (Y32K) resulted in a small (5-fold) inhibition of PBD binding, but the very conservative mutation D38E yielded at least a 50-fold decrease in affinity. Finally, the catalytic domain of the GTPase activating protein, Cdc42-GAP, was shown to inhibit PBD binding in a competitive manner, indicating that this target molecule and the negative regulator (GAP) bind to overlapping sites on the Cdc42Hs molecule.     

The signal recognition particle receptor of Escherichia coli (FtsY) has a nucleotide exchange factor built into the GTPase domain

Targeting of many secretory and membrane proteins to the inner membrane in Escherichia coli is achieved by the signal recognition particle (SRP) and its receptor (FtsY). In E. coli SRP consists of only one polypeptide (Ffh), and a 4.5S RNA. Ffh and FtsY each contain a conserved GTPase domain (G domain) with an alpha-helical domain on its N terminus (N domain). The nucleotide binding kinetics of the NG domain of the SRP receptor FtsY have been investigated, using different fluorescence techniques. Methods to describe the reaction kinetically are presented. The kinetics of interaction of FtsY with guanine nucleotides are quantitatively different from those of other GTPases. The intrinsic guanine nucleotide dissociation rates of FtsY are about 10(5) times higher than in Ras, but similar to those seen in GTPases in the presence of an exchange factor. Therefore, the data presented here show that the NG domain of FtsY resembles a GTPase-nucleotide exchange factor complex not only in its structure but also kinetically. The I-box, an insertion present in all SRP-type GTPases, is likely to act as an intrinsic exchange factor. From this we conclude that the details of the GTPase cycle of FtsY and presumably other SRP-type GTPases are fundamentally different from those of other GTPases.     

Phase III trial of neoadjuvant chemotherapy in patients with invasive bladder cancer treated with selective bladder preservation by combined radiation therapy and chemotherapy: initial results of Radiation Therapy Oncology Group 89-03

PURPOSE: To assess the efficacy of neoadjuvant methotrexate, cisplatin, and vinblastine (MCV) chemotherapy in patients with muscle-invading bladder cancer treated with selective bladder preservation. PATIENTS AND METHODS: One hundred twenty-three eligible patients with tumor, node, metastasis system clinical stage T2 to T4aNXMO bladder cancer were randomized to receive (arm 1, n=61 ) two cycles of MCV before 39.6-Gy pelvic irradiation with concurrent cisplatin 100 mg/m2 for two courses 3 weeks apart. Patients assigned to arm 2 (n=62) did not receive MCV before concurrent cisplatin and radiation therapy. Tumor response was scored as a clinical complete response (CR) when the cystoscopic tumor-site biopsy and urine cytology results were negative. The CR patients were treated with an additional 25.2 Gy to a total of 64.8 Gy and one additional dose of cisplatin. Those with less than a CR underwent cystectomy. The median follow-up of all patients who survived is 60 months. RESULTS: Seventy-four percent of the patients completed the protocol with, at most, minor deviations; 67% on arm 1 and 81% on arm 2. The actuarial 5-year overall survival rate was 49%; 48% in arm 1 and 49% in arm 2. Thirty-five percent of the patients had evidence of distant metastases at 5 years; 33% in arm 1 and 39% in arm 2. The 5-year survival rate with a functioning bladder was 38%, 36% in arm 1 and 40% in arm 2. None of these differences are statistically significant. CONCLUSION: Two cycles of MCV neoadjuvant chemotherapy were not shown to increase the rate of CR over that achieved with our standard induction therapy or to increase freedom from metastatic disease. There was no impact on 5-year overall survival.     

MR of spinal cord ganglioglioma

PURPOSE: Our purpose was to describe the MR imaging features in a series of spinal intramedullary gangliogliomas and to compare these findings with the MR features of intramedullary astrocytomas and ependymomas. METHODS: A retrospective analysis was performed of 76 MR examinations in 27 patients with histologically proved spinal ganglioglioma; these were then compared with imaging findings in a representative sample of histologically proved spinal cord astrocytomas and ependymomas. RESULTS: Statistically significant observations regarding spinal gangliogliomas included young age of the patients (mean, 12 years), long tumor length, presence of tumoral cyst, presence of bone erosion and scoliosis, absence of edema, presence of mixed signal intensity on T1-weighted images, and presence of patchy enhancement and cord surface enhancement. A trend (not statistically significant) was noted for holocord involvement and lack of magnetic susceptibility. CONCLUSION: Spinal ganglioglioma can be strongly suspected if MR images reflect the above criteria; however, the ultimate diagnosis still depends on radical resection and appropriate histopathologic investigation.     

Intraoperative placement of a Wallstent for portal vein stenosis and thrombosis after liver transplantation

We report a case of orthotopic liver transplantation, in which portal vein thrombosis developed in the immediate postoperative period. Surgical thrombectomy and intraoperative placement of a large caliber Wallstent resulted in long-term patency. The unique feature of this case is the intraoperative placement of the stent via the inferior mesenteric vein under fluoroscopic guidance. The use of a large caliber (16 mm) stent obviated the need for postoperative anticoagulation.     

Design of applicators for a 27 MHz multielectrode current source interstitial hyperthermia system; impedance matching and effective power

In interstitial heating one of the main requirements for achieving a certain elevated temperature in a tumour is that the effective power per applicator (Peff), i.e. the power which is actually deposited in the tissue, is sufficiently high. In this paper this requirement is discussed for the applicators of the 27 MHz multielectrode current source (MECS) interstitial hyperthermia (IHT) system. To minimize power reflection, the applicator impedance was matched with the generator impedance by adjusting the length of the coaxial cable in between. Transmission line losses, applicator efficiency and subsequently Peff were computed for several applicator types. The actual Peff per electrode was obtained from calorimetric measurements. Experiments with RC loads, which can be seen as perfect applicators, were performed to investigate the effect of mismatching on Peff. Applicator losses were measured for clinically used applicators, both single- and dual-electrode, utilizing saline phantoms. A simple spherical tumour model, using the effective heat conductivity (keff) to account for heat transport, was used to estimate Peff for a given tumour size, implant size and applicator density. Computations of Peff of various MECS-IHT electrodes were in close agreement with the phantom measurements. Most of the initial generator power was absorbed in the transmission line (60-65%). The efficiency of the applicators was about 65%. For both single- and dual-electrode applicators the effective electrode power was found to be about 1 W. Model calculations show that Peff of 1 W is sufficient to reach a minimum tumour temperature of 43 degrees C in well perfused tumours (keff = 3 W m-1 degree C-1), using a typical implant with 2 cm electrodes and 1.5 cm spacing. Mismatching can considerably affect Peff. Both a reduction to almost zero and a two-fold increase are possible. However, because the matching theory is well understood, mismatching is not a serious problem in clinical practice and can even be used to increase Peff if necessary. We conclude that the applicator design and the impedance matching method chosen in the MECS system allow heating to temperatures in the therapeutic range with implants used in clinical practice.