Gardnerella vaginalis is an important component of the human vaginal microflora. It is proposed to play a key role in the pathogenesis of bacterial vaginosis (BV), the most common vaginal condition. Here we describe the development, validation and comparative analysis of a novel molecular approach capable of G. vaginalis identification, quantification and subtyping in noncultured vaginal specimens. Using two quantitative PCR (qPCR) assays, we analysed G. vaginalis bacterial loads and clade distribution in 60 clinical vaginal-swab samples. A very high pathogen prevalence was revealed by species-specific qPCR not only among BV patients (100 %), but also in healthy women (97 %), although the G. vaginalis concentration was significantly lower in non-BV samples. G. vaginalis clades identified in vaginal specimens by subtyping multiplex qPCR, which targets four clade-specific genetic markers, had frequencies of 53 % for
PCR analysis of Ixodes scapularis ticks collected in New Jersey identified infections with Borrelia burgdorferi (33.6%), Babesia microti (8.4%), Anaplasma phagocytophila (1.9%), and Bartonella spp. (34.5%). The I. scapularis tick is a potential pathogen vector that can cause coinfection and contribute to the variety of clinical responses noted in some tick-borne disease patients
Erythromycin (EM) and clindamycin (CM) susceptibility testing was performed on 222 clinical isolates of group B Streptococcus. A multiplex PCR assay was used to detect the ermB, ermTR, and mefA/E antibiotic resistance genes. These results were compared to the phenotypes as determined by the standard EM/CM double disk diffusion assay.Group B Streptococcus (GBS) is one of the leading causes of neonatal bacterial infection. This type of infection commonly leads to pneumonia, septicemia, or meningitis. Because of the serious nature of neonatal GBS infections, the suggested standard protocol for the obstetrician/gynecologist is that pregnant women should be tested for the presence of GBS at 35 to 37 weeks of gestation (7,15). Once GBS colonization is diagnosed, the typical treatment for these patients is penicillin, to which there is no known resistance. However, there is a significant population of penicillin-allergic patients, a reported 12% of pregnant women (12), for whom the macrolide (erythromycin [EM]) or lincosamide (clindamycin [CM]) class of drugs needs to be administered, in particular, for those patients who are at high risk for anaphylactic shock. Previous reports have cited resistance of GBS to EM and CM of up to 37% and 17%, respectively (7). The resistance is commonly caused by three genes: ermB, ermTR, and mefA/E (1, 9, 10). The ermB and ermTR genes encode 23S rRNA methylases, which alter the binding of the antibiotic target site. The expression of these genes leads to the constitutively expressed and the erythromycin-induced macrolide, lincosamide, and streptogramin B (cMLS and iMLS, respectively) resistance phenotypes (9). The mefA and mefE genes, which are 90% identical, encode 14-and 15-member macrolide efflux pumps and lead to the macrolide only (M) resistance phenotype (1). Because of the presence of ermB, ermTR, mefA/E, and other antibiotic resistance genes on plasmids and/or transposons, these genes can pass from organism to organism, and the monitoring of the antibiotic resistance of GBS should occur regularly (13). We used a multiplex PCR assay to screen for the prevalence of the ermB, ermTR, and mefA/E genes in GBS clinical isolates from 222 patients for whom physicians ordered GBS testing. The samples, representing 20 states in the United States and 60% of which were from Florida, New Jersey, and Texas, were chosen at random. Patient ages ranged from 15 to 82 years, with an average of 31.3 Ϯ 11.8 years. These results were compared to the antibiotic resistance phenotypes as determined by the standard EM/CM double disk diffusion assay (3,11,15)
A retrospective survey of 93,775 samples testing positive in Candida species-specific PCR tests performed on cervicovaginal swabs over a 4-year period demonstrated consistent yearly distributions of Candida albicans (89%), C. glabrata (7.9%), C. parapsilosis (1.7%), and C. tropicalis (1.4%). However, the species distributions among different age groups revealed increases in the percentages of non-albicans species with increases in age.Vulvovaginal candidiasis (VVC) is a common fungal infection that affects healthy women of all ages. At least 75% of women will develop one or more infections once during their lifetime, with 5 to 8% of those individuals developing recurrent infections (5, 7). Current literature examining the species distribution of Candida isolates involved in VVC is limited; however, several important observations have been made. For example, one study shows that Candida albicans accounts for 70 to 90% of all VVC cases, with a recent emergence of nonalbicans species (10). The rise in VVC infections, more specifically in those caused by non-albicans species, could be due to several factors, ranging from an increase in over-the-counter antifungal use to an increase in high-risk patient populations (i.e., diabetics and menopausal women). Candida glabrata is the primary non-albicans species emerging in VVC, accounting for up to 14% of infections in immune-competent women (9, 10).In addition to an increase in non-albicans species overall, it is becoming clear that certain patient populations may experience higher risks of infection from these non-albicans species, often leading to limited treatment options. Interestingly, in a few small studies, C. glabrata was found to be the primary species isolated from diabetic (61.3%) and elderly (51.2%) patients with VVC (2, 4, 6, 11). Often, these non-albicans species are associated with elevated MIC levels for the azoles, the most commonly prescribed class of antifungal drugs. It has been well documented that C. glabrata demonstrates both intrinsically low susceptibility to the azoles and the ability to develop frank resistance (8,12,13,14,15,16). Moreover, a recent increase in the trailing phenotype, with low-level resistance to the azoles, has been observed for the Candida tropicalis isolates (1, 3). This highlights the importance of identifying Candida species within clinical samples in order to provide physicians with information concerning the proper treatment for their patients.
Podoplanin (PDPN) is a unique transmembrane receptor that promotes tumor cell motility. Indeed, PDPN may serve as a chemotherapeutic target for primary and metastatic cancer cells, particularly oral squamous cell carcinoma (OSCC) cells that cause most oral cancers. Here, we studied how a monoclonal antibody (NZ-1) and lectin (MASL) that target PDPN affect human OSCC cell motility and viability. Both reagents inhibited the migration of PDPN expressing OSCC cells at nanomolar concentrations before inhibiting cell viability at micromolar concentrations. In addition, both reagents induced mitochondrial membrane permeability transition to kill OSCC cells that express PDPN by caspase independent nonapoptotic necrosis. Furthermore, MASL displayed a surprisingly robust ability to target PDPN on OSCC cells within minutes of exposure, and significantly inhibited human OSCC dissemination in zebrafish embryos. Moreover, we report that human OSCC cells formed tumors that expressed PDPN in mice, and induced PDPN expression in infiltrating host murine cancer associated fibroblasts. Taken together, these data suggest that antibodies and lectins may be utilized to combat OSCC and other cancers that express PDPN.
c Bacterial vaginosis (BV) is the most common gynecological infection in the United States. Diagnosis based on Amsel's criteria can be challenging and can be aided by laboratory-based testing. A standard method for diagnosis in research studies is enumeration of bacterial morphotypes of a Gram-stained vaginal smear (i.e., Nugent scoring). However, this technique is subjective, requires specialized training, and is not widely available. Therefore, a highly accurate molecular assay for the diagnosis of BV would be of great utility. We analyzed 385 vaginal specimens collected prospectively from subjects who were evaluated for BV by clinical signs and Nugent scoring. We analyzed quantitative real-time PCR (qPCR) assays on DNA extracted from these specimens to quantify nine organisms associated with vaginal health or disease: Gardnerella vaginalis, Atopobium vaginae, BV-associated bacteria 2 (BVAB2, an uncultured member of the order Clostridiales), Megasphaera phylotype 1 or 2, Lactobacillus iners, Lactobacillus crispatus, Lactobacillus gasseri, and Lactobacillus jensenii. We generated a logistic regression model that identified G. vaginalis, A. vaginae, and Megasphaera phylotypes 1 and 2 as the organisms for which quantification provided the most accurate diagnosis of symptomatic BV, as defined by Amsel's criteria and Nugent scoring, with 92% sensitivity, 95% specificity, 94% positive predictive value, and 94% negative predictive value. The inclusion of Lactobacillus spp. did not contribute sufficiently to the quantitative model for symptomatic BV detection. This molecular assay is a highly accurate laboratory tool to assist in the diagnosis of symptomatic BV.
Recent studies have shown that nondividing primary cells, such as hepatocytes, can be efficiently transduced in vitro by human immunodeficiency virus-based lentivirus vectors. Other studies have reported that, under certain conditions, the liver can be repopulated with transplanted hepatocytes. In the present study, we combined these procedures to develop a model system for ex vivo gene therapy by repopulating rat livers with hepatocytes and hepatoblasts transduced with a lentivirus vector expressing a reporter gene, green fluorescent protein (GFP). Long-term GFP expression in vivo (up to 4 months) was achieved when the transgene was driven by the liver-specific albumin enhancer/promoter but was silenced when the cytomegalovirus (CMV) enhancer/promoter was used. Transplanted cells were massively amplified (ϳ10 cell doublings) under the influence of retrorsine/partial hepatectomy, and both repopulation and continued transgene expression in individual cells were documented by dual expression of a cell transplantation marker, dipeptidyl peptidase IV (DPPIV), and GFP. In this system, maintenance or expansion of the transplanted cells did not depend on expression of the transgene, establishing that positive selection is not required to maintain transgene expression following multiple divisions of transplanted, lentivirus-transduced hepatic cells. In conclusion, fetal hepatoblasts (liver stem/progenitor cells) can serve as efficient vehicles for ex vivo gene therapy and suggest that liver-based genetic disorders that do not shorten hepatocyte longevity or cause liver damage, such as phenylketonuria, hyperbilirubinemias, familial hypercholesterolemia, primary oxalosis, and factor IX deficiency, among others, might be amenable to treatment by this approach. (HEPATOLOGY 2003;37:994-1005.)
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