Failure to Detect the Presence of Prions in the Uterine and Gestational Tissues from a Gravida with Creutzfeldt-Jakob Disease

The vertical transmission of a prion disease from infected mothers to their offspring is believed to be one of the routes for the natural spread of animal prion diseases. Supporting this notion is the observation that prion infectivity occurs in the placenta of infected ewes. Furthermore, the prion protein (PrP), both in its cellular form (PrP^C) and its pathological isoform (PrP^Sc), has been observed at the fetal-maternal interface of scrapie-infected sheep. However, whether these features of prion infectivity also hold true for human prion diseases is currently unknown. To begin to address such an important question, we examined PrP in the uterus as well as gestational tissues, including the placenta and amniotic fluid, in a pregnant woman with sporadic Creutzfeldt-Jakob disease (CJD). Although the proteinase K (PK)-resistant prion protein, PrP27-30, was present in the brain tissues of the mother, the PrP detected in the uterus, placenta, and amniotic fluid was sensitive to PK digestion. Unlike PrP^C in the brain and adjacent cerebrospinal fluid, the predominant PrP species in the reproductive and gestational tissues were N-terminally truncated, similar to urine PrP. Our study did not detect abnormal PrP in the reproductive and gestational tissues in this case of CJD. Nevertheless, examination by a highly sensitive bioassay is ongoing to ascertain possible prion infectivity from CJD in the amniotic fluid.The transmissible prion diseases affecting both humans and animals are characterized by the accumulation of an infectious prion protein particle (PrP^Sc) mainly in the central nervous system (CNS) and occasionally in the peripheral tissues.^1,2,3,4 Animal prion diseases such as scrapie in sheep and goats, chronic wasting disease in deer and elks, and bovine spongiform encephalopathy in cattle are believed to spread naturally by oral transmission, close contact between animals, and maternal transmission. Indeed, Western blot analysis and bioassays have demonstrated that PrP^Sc and prion infectivity are present not only in the CNS, but also in many peripheral tissues including the tonsils, spleen, lymph nodes, nasal mucosa, distal colon, ovaries, uterus, skeletal muscle, placenta, and amniotic fluid of affected animals.²In humans, the transmission of prion diseases has been observed in the acquired form of the disease including kuru, iatrogenic Creutzfeldt-Jakob disease (iCJD), and variant CJD (vCJD).⁵ Kuru is associated with cannibalistic rituals,^6,7 whereas iCJD is caused by prion exposure in the course of medical or surgical procedures, and vCJD has been attributed to the consumption of prion-contaminated meat.^8,9 In addition to CNS, PrP^Sc has also been detected in the tonsils, spleen, lymph node, retina, optic nerve, rectum, adrenal gland, and thymus of vCJD and in the spleen and skeletal muscles of sporadic CJD (sCJD).^3,4 However, it remains unknown whether human prion diseases are vertically transmitted in pregnancy. For instance, none of four offspring born to four gravid women with CJD had reportedly developed the disease when they reached the respective ages of 22, 10, 7, and 3 years.¹⁰ In addition, no reports are available concerning examination of PrP in the uterus and gestational tissues from prion-affected patients.We examined PrP^Sc distribution in CNS, uterus, and gestational tissues from a woman affected with prion disease, who had become pregnant and delivered a baby boy during the time she had the disease. Typical PK-resistant PrP core fragments and neuropathological changes, characteristic of sCJD (with PrP^Sc type 1 carrying a valine/valine polymorphism at codon 129 of PrP gene), were detected in the brain tissues obtained at either biopsy or autopsy. Although PrP was detectable in the uterus, placenta, and amniotic fluid, it was PK-sensitive. Moreover, neither conventional nor enrichment-based Western blot analysis revealed the presence of abnormal PrP species. In contrast to the PrP in the brain and cerebrospinal fluid (CSF), the PrP detected in the uterus and gestational tissues, including placenta and amniotic fluid, was N-terminally truncated, similar to that normally found in the urine. Although the presence of prion infectivity in tissue remains to be determined by highly sensitive bioassay, our current study suggests that abnormal PrP species, including both PK-resistant and PK-sensitive forms, are undetectable in the uterus and gestational tissues in sporadic CJD.     

Heterogeneity in the granulomatous response to mycobacterial infection in patients with defined genetic mutations in the interleukin 12-dependent interferon-gamma production pathway

Patients with genetic lesions in the Type-1 cytokine/cytokine receptor pathway exhibit a selective susceptibility to severe infections with poorly pathogenic mycobacteria and non-typhi salmonella spp. These experiments of nature demonstrate that IL-12-dependent IFNgamma production is critical for granuloma formation and therefore host immunity against such pathogens. The essential role of granuloma formation for protective immunity to these organisms is emphasized by the differing granuloma forming capabilities and resultant clinical sequelae observed in these patients which seems to reflect their ability to produce or respond to IFNgamma (Fig. 9). At one pole of this spectrum, represented by the complete IFNgammaR1/2 deficient patients, there is a complete absence of mature granuloma formation, whereas with the less severe mutations (i.e. partial IFNgammaR1/2, complete IL-12p40 and complete IL-12Rbeta1 deficiency), granuloma formation is very heterogenous with wide variations in composition being observed. This suggests that in the latter individuals, who produce partial but suboptimal IFNgamma responses, other influences, including pathogen virulence and host genotype may also affect the type and scale of the cellular response elicited.     

c-kit Expression in small cell carcinoma of the urinary bladder: prognostic and therapeutic implications.

The prognosis for small cell carcinoma of the urinary bladder is poor, and strategies for improved therapy are needed. Targeted therapy against the c-kit proto-oncogene has been successful in the management of gastrointestinal stromal tumor. We investigated the expression of c-kit in 52 cases of small cell carcinoma of the urinary bladder. Specimens with more than 10% of cells demonstrating strong membrane staining were considered to have positive immunostaining for c-kit. c-kit expression was detected in 21 of 52 specimens from these patients. Among the 21 specimens, seven had less than 10% staining, and were considered to be negative. Nine had 11-50% staining, and five had more than 50% staining. Overall, 14 of 52 (27%) small cell carcinomas of the urinary bladder were positive for c-kit expression. During a median follow-up of 11 months, 60% of the patients died of bladder cancer. No association was found between c-kit expression and survival or other clinicopathologic parameters. Five-year cancer-specific survivals for c-kit-positive and c-kit-negative tumors were 9 and 15%, respectively (P=0.36). A significant proportion (27%) of small cell carcinomas of the urinary bladder expressed c-kit, suggesting that it may prove useful as a therapeutic target in small cell carcinoma of the urinary bladder.     

How effective is patient-controlled analgesia? A randomized comparison of two protocols for pain relief during oocyte recovery

Although the conventional method of pain relief during outpatient oocyte recovery involves physician-administered drugs, patient- controlled analgesia (PCA) offers an alternative technique with the potential to give women more control over peroperative analgesia. We conducted a prospective randomized study to compare the effect of fentanyl administered either through a PCA delivery system or by a physician. Thirty-nine women were randomized to PCA during egg collection while 42 were allocated to receive intermittent doses administered by a physician. Pain was evaluated by means of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P = 0.1). In the PCA group, 64% of women felt very satisfied with their analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the PCA users, 39% of demands were successful. Significantly more fentanyl (97.5 microg) was used in the PCA group than in the other group (84.6 microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective alternative to physician-administered techniques, many women still feel the need for more analgesia during the procedure.      

Chromophobe renal cell carcinoma: a comparative study of histological, immunohistochemical and ultrastructural features using high throughput tissue microarray

AIMS: In some cases distinction between chromophobe renal cell carcinoma (CRCC), oncocytoma and clear cell (conventional) renal cell carcinoma (eosinophilic variant) using routine light microscopy remains problematic. The present study investigates the level of agreement in the diagnosis of CRCC, as well as the histological features most frequently used for this diagnosis by two pathologists with a special interest in renal neoplasia. The sensitivity and specificity of immunohistochemical markers in cases with overlapping histological features in the diagnosis of CRCC were also studied. Electron microscopy was performed, as a diagnostic gold standard, on all of the cases. METHODS AND RESULTS: Thirty-two renal tumours with predominantly eosinophilic cytoplasm were reviewed in a blinded fashion by two pathologists. The diagnosis and morphological features used to render each diagnosis were tabulated. Validation of the utility of keratin 7 and 20, epithelial membrane antigen (EMA), vimentin, CD10, parvalbumin, RCC antigen, antimitochondrial antibody and Hale's colloidal iron was performed by the construction of a tissue microarray (TMA) master block. Based on histological criteria alone, overall agreement on the diagnosis of these tumours was reached in 69% of the cases, while there was total disagreement in 12%. In 59% of the cases, total agreement was reached in classifying the case as a CRCC based on histology alone. Kappa statistics for interobserver variability were calculated as only slight agreement (kappa = 0.3). The histological features most frequently associated with a diagnosis of CRCC were accentuated cell borders (87%) and a combination of hyperchromatic wrinkled nuclei (79%) and perinuclear halos (74%). The most sensitive and specific marker for CRCC was parvalbumin (sensitivity 0.91; specificity 1.0). The immunohistochemical profile of EMA+/ vimentin- was useful but had low specificity (sensitivity 0.75; specificity 0.4). CD10 had the highest sensitivity (1.0) but worst specificity (0.25) for CRCC. Keratin 7 had high sensitivity (0.83) but fairly low specificity (0.37) for CRCC. Hale's colloidal iron and the RCC antigen marker were not contributory. Finally, the antimitochondrial antibody was found to be fairly sensitive (0.83) for excluding CRCC. CONCLUSIONS: A small but significant proportion of renal tumours with cells having eosinophilic cytoplasm cannot be classified, even by experienced pathologists, based on histology alone. In these cases it is imperative to use markers with known sensitivity and specificity for the diagnosis of CRCC.     

Soluble flagellin, FliC, induces an Ag-specific Th2 response, yet promotes T-bet-regulated Th1 clearance of Salmonella typhimurium infection

Clearance of disseminated Salmonella infection requires bacterial-specific Th1 cells and IFN-γ production, and Th1-promoting vaccines are likely to help control these infections. Consequently, vaccine design has focused on developing Th1-polarizing adjuvants or Ag that naturally induce Th1 responses. In this study, we show that, in mice, immunization with soluble, recombinant FliC protein flagellin (sFliC) induces Th2 responses as evidenced by Ag-specific GATA-3, IL-4 mRNA, and protein induction in CD62L(lo) CD4(+) T cells without associated IFN-γ production. Despite these Th2 features, sFliC immunization can enhance the development of protective Th1 immunity during subsequent Salmonella infection in an Ab-independent, T-cell-dependent manner. Salmonella infection in sFliC-immunized mice resulted in augmented Th1 responses, with greater bacterial clearance and increased numbers of IFN-γ-producing CD4(+) T cells, despite the early induction of Th2 features to sFliC. The augmented Th1 immunity after sFliC immunization was regulated by T-bet although T-bet is dispensable for primary responses to sFliC. These findings show that there can be flexibility in T-cell responses to some subunit vaccines. These vaccines may induce Th2-type immunity during primary immunization yet promote Th1-dependent responses during later infection. This suggests that designing Th1-inducing subunit vaccines may not always be necessary since this can occur naturally during subsequent infection.     

Pathology of flat bladder lesions with emphasis on putative precursors

Flat bladder lesions comprise a spectrum of morphologic changes ranging from reactive atypia to carcinoma in situ (CIS). Differentiating these lesions is important because of differences in patient management and clinical outcome. The precise nature of precursor lesions of bladder cancer remains incompletely understood. Urothelial CIS is the most definitely characterized precursor lesion of high grade bladder cancer. Atypia of unknown significance (AUS) is somewhat controversial. For practical purposes, AUS and reactive urothelial changes should be considered a single entity, since neither lesion has established preneoplastic potential. Simple hyperplasia and papillary hyperplasia are recently identified putative preneoplastic lesions. More recent molecular data also support the precursor nature of intestinal metaplasia and keratinizing squamous metaplasia. In this review, we also discuss the utility of molecular ancillary studies in establishing premalignant lesions, diagnosis, and differential diagnosis of flat bladder lesions.