Persistent infections support maintenance of a coronavirus in a population of Australian bats (Myotis macropus).

Understanding viral transmission dynamics within populations of reservoir hosts can facilitate greater knowledge of the spillover of emerging infectious diseases. While bat-borne viruses are of concern to public health, investigations into their dynamics have been limited by a lack of longitudinal data from individual bats. Here, we examine capture-mark-recapture (CMR) data from a species of Australian bat (Myotis macropus) infected with a putative novel Alphacoronavirus within a Bayesian framework. Then, we developed epidemic models to estimate the effect of persistently infectious individuals (which shed viruses for extensive periods) on the probability of viral maintenance within the study population. We found that the CMR data analysis supported grouping of infectious bats into persistently and transiently infectious bats. Maintenance of coronavirus within the study population was more likely in an epidemic model that included both persistently and transiently infectious bats, compared with the epidemic model with non-grouping of bats. These findings, using rare CMR data from longitudinal samples of individual bats, increase our understanding of transmission dynamics of bat viral infectious diseases.

Apolipoprotein E epsilon4 and testosterone interact in the risk of Alzheimer's disease in men.

OBJECTIVES: To assess the association between testosterone levels and APOEepsilon4 in cases with AD and controls. METHOD: We included 61 men with definite or probable Alzheimer's disease (AD) and 55 elderly male controls from the Oxford Project to Investigate Memory and Ageing (OPTIMA). Testosterone was measured using a competitive enzyme immunoassay (Bayer). RESULTS: We found that both low serum testosterone and the interaction between testosterone and APOEepsilon4 were associated with AD. Furthermore, testosterone levels were lower in APOEepsilon4-positive controls (mean: 11.3 nmol/L) than in controls without the allele (19.1 nmol/L). CONCLUSIONS: Low testosterone is potentially a modifiable risk factor, which may prove relevant to APOEepsilon4 carriers who are at risk of AD.

Using meta-analysis to explain the diversity of results in genetic studies of late-onset Alzheimer's disease and to identify high-risk subgroups.

In late-onset Alzheimer's disease, there is a puzzling inconsistency between the findings of case-control studies of most proposed risk genes, except apolipoprotein E epsilon4. This inconsistency may stem from the failure to define the genetic and non-genetic interactions that affect the disease association of each particular susceptibility gene. Such interactions will limit the influence of the gene to a 'relevant subset' of vulnerable people. The relevant subsets for many risk genes will be narrow, compared to that of apolipoprotein E epsilon4. Studies may therefore miss the association or even suggest that a risk gene is protective. In these circumstances, the precise composition of a cohort is critical and defining the relevant subset is crucial. We illustrate how such definition may be achieved through meta-analysis. We take as an example the butyrylcholinesterase K variant, whose association with Alzheimer's disease may now be provisionally defined. This analysis leads to the identification of a potentially high-risk group: over 75 year old male carriers of both apolipoprotein E epsilon4 and butyrylcholinesterase K variant.

Uterine adenosarcoma with sarcomatous overgrowth versus uterine carcinosarcoma: comparison of treatment and survival.

OBJECTIVE: Uterine adenosarcoma with sarcomatous overgrowth (ASSO) is a rare variant of uterine sarcoma first described in 1989. This clinicopathologic study was undertaken to compare the treatment and survival of uterine adenosarcoma with sarcomatous overgrowth to that of uterine carcinosarcomas. METHODS: A review of uterine sarcomas diagnosed at Washington Hospital Center from January 1988 to December 1998 was performed. Records were reviewed for demographic data, surgical staging, primary and adjuvant therapy, metastatic site, disease recurrence, and survival. All pathology was reviewed and diagnosis confirmed. Statistical analysis included chi(2) test and Student's t test. Kaplan-Meier survival curves were plotted to estimate the median and 5-year survival times. The log-rank test was used to compare survival times. A P value <0.05 was considered significant. RESULTS: Sixty patients were diagnosed with uterine sarcoma at Washington Hospital Center. Of these, 33 (55%) were uterine carcinosarcomas, 11 (18%) ASSOs, 6 (10%) adenosarcomas, and 10 (17%) leiomyosarcomas. Of the patients diagnosed with uterine ASSO, 3 (27%) were stage I, 3 (27%) stage II, 1 (9%) stage III, and 4 (36%) stage IV. All 11 patients with uterine ASSO underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and tumor debulking. Postoperative adjuvant therapy included chemotherapy (n = 4), radiation (n = 4), combination radiation and chemotherapy (n = 1), and no adjuvant therapy (n = 2). The overall median survival time of patients with uterine ASSO was 13 months. Nine of eleven patients are dead of disease, and two patients (both with stage I) are alive without evidence of disease at 18 and 19 months. Thirty-three patients with carcinosarcoma were identified, with follow-up available on 29 patients. Of these, 10 (34%) were stage I, 6 (22%) stage II, 3 (10%) stage III, and 10 (34%) stage IV. Twenty-seven of the twenty-nine patients diagnosed with carcinosarcoma underwent surgical therapy to include total abdominal hysterectomy, bilateral salpingo-oophorectomy, staging and tumor debulking. Two patients died prior to treatment. Postoperative adjuvant therapy included chemotherapy (n = 9), radiation (n = 13), combination (n = 1), and no further therapy (n = 4). Twenty of the twenty-nine patients are dead of disease; there were nine surviving patients at the time of this report (stage I-5, stage II-3, stage III-1). The median survival of these patients was 31 months, with an overall 5-year survival of 22%. Comparison of the Kaplan-Meier survival curves using the log-rank test suggests a worse prognosis for uterine ASSO. However, this did not reach statistical significance (P = 0.0522). CONCLUSIONS: Patients diagnosed with uterine ASSO have a poor prognosis similar to that of carcinosarcoma. Management should include complete surgical staging. Additional therapy in the form of radiation, chemotherapy, or both has been reported; however, the superiority of one modality could not be determined from our data.

Modelling of endemic carriage of Haemophilus influenzae in Aboriginal infants in Northern Australia.

Aboriginal infants and children in rural communities in Northern Australia have high rates of nasopharyngeal carriage of nonencapsulated Haemophilus influenzae (NCHi), with positive swab rates of 76%. In this population, the acquisition of NCHi from soon after birth is associated with the onset of otitis media and with muco-purulent nasal discharge, while the long-term persistence of NCHi carriage is associated with the acquisition and turnover of large numbers of antigenically diverse strains. Mathematical models have been fitted to data on the acquisition and loss of encapsulated strains of H. influenzae and 43 different strains of NCHi in 10 children followed from early infancy for up to 2 years. Subject to plausible assumptions, the preferred model estimated the mean time to acquisition of a H. influenzae strain to be 7 days after first becoming exposed after birth. For an infant already carrying H. influenzae, each additional strain was acquired after a mean waiting period of 45 days. On average, 1.50 different strains of H. influenzae were detected in four colonies routinely typed from each positive swab, but it was estimated that another 2.55 strains were 'hidden' behind these more frequent strains. With an average of 4.05 strains per carrier, it was estimated that each strain was carried for an average of 137 days, although detected on only 37% of occasions. Thus we have developed mathematical models that provide estimates for duration of colonisation, time to colonisation, and number of colonising strains in a population in which H. influenzae is highly endemic, characterised by sequential and concurrent carriage of multiple strains in each infant.

Cervical adenocarcinoma in situ: a systematic review of therapeutic options and predictors of persistent or recurrent disease.

The incidence of cervical adenocarcinoma in situ is increasing in frequency, and our limited knowledge about this lesion presents the physician with a therapeutic dilemma. Treatment for this lesion has included conservative therapy, large loop excision or cold-knife cone biopsy, or definitive therapy consisting of hysterectomy. But, rates of residual adenocarcinoma in situ after cone biopsy with negative margins vary from 0% to 40%, and residual disease rates as high as 80% have been noted when the margins are positive. Despite these recent data on follow-up after conservative therapy such as cone biopsy, it seems that this method is safe and gaining acceptance by many physicians and patients. However, the short follow-up duration and small number of patients limit the conclusions of many studies. The relative infrequency of this diagnosis has precluded extensive clinical experience with the natural history of this lesion.

Large cell neuroendocrine cervical carcinoma: a report of two cases and review of the literature.

BACKGROUND: Large cell neuroendocrine cervical carcinoma is a rare malignancy. These tumors appear to mimic the aggressive behavior of small cell neuroendocrine tumors. Metastasis and recurrent disease are common. Due to the low incidence of these tumors, optimal therapy has not been delineated. CASES: Two patients presented with large cell neuroendocrine cervical carcinoma, stage IB1 and IIA, at our institution from 1997 to 1999. We describe the clinical course for these two patients and review the relevant literature for the management of large cell cervical carcinoma. CONCLUSION: Unlike squamous cell carcinoma, early-stage large cell neuroendocrine tumors of the cervix are aggressive. Disease recurrences are frequent and distant metastasis is common. Multimodal therapy should be considered at the time of initial diagnosis.

Abnormal fragile histidine triad (FHIT) expression in advanced cervical carcinoma: a poor prognostic factor.

The FHIT gene is a candidate tumor suppressor gene that has been implicated in the development of cervical carcinoma. We hypothesized that abnormal Fhit expression might be a poor prognostic factor for patients with cervical cancer. The tumors from 59 high-risk patients (stage II-III) were evaluated for abnormal Fhit expression by immunohistochemical staining. Abnormal Fhit expression (absent or reduced) was noted in 66% of the specimens. There was no statistical difference with respect to stage, performance status, para-aortic node metastasis, completion of therapy, grade, race, age, and HIV status between the normal and abnormal Fhit expression groups. The 3-year survival for patients whose tumors displayed normal Fhit expression versus abnormal Fhit expression was 74% versus 37%, respectively. Univariate analysis demonstrated a difference in survival that was statistically significant for age <55 years versus > or =55 years (P = 0.015), normal Fhit expression versus abnormal Fhit expression (P = 0.015), and stage II versus stage III (P = 0.033). Multivariate analysis showed that abnormal Fhit expression was a poor prognostic factor (P = 0.015).

Persistent ICT malaria P.f/P.v panmalarial and HRP2 antigen reactivity after treatment of Plasmodium falciparum malaria is associated with gametocytemia and results in false-positive diagnoses of Plasmodium vivax in convalescence.

A problem with rapid Plasmodium falciparum-specific antigen histidine-rich protein 2 (HRP2) detection tests for malaria is the persistence of antigen in blood after the disappearance of asexual-stage parasitemia and clinical symptoms, resulting in false-positive (FP) test results following treatment. The ICT P.f/P.v immunochromatographic test detects both HRP2 and a panmalarial antigen (PMA) found in both P. falciparum and Plasmodium vivax. To examine posttreatment antigen persistence with this test and whether persistent sexual-stage forms (gametocytes) are a cause of FP tests after treatment, we compared serial antigen test results with microscopy results from patients symptomatic with P. falciparum malaria in Indonesia for 28 days following treatment with chloroquine (CQ; n = 66), sulfadoxine-pyrimethamine (SP; n = 36), and artesunate plus sulfadoxine-pyrimethamine (ART + SP; n = 15). Persistent FP antigenemia following SP treatment occurred in 29% (HRP2) and 42% (PMA) of the patients on day 7 and in 10% (HRP2) and 23% (PMA) on day 14. The high rates of persistent HRP2 and PMA antigenemia following CQ and SP treatment were strongly associated with the presence of gametocytemia, with the proportion with gametocytes on day 7 posttreatment being significantly greater in those with FP results than in those with true-negative PMA and HRP2 results. Gametocyte frequency on day 14 post-SP treatment was also greater in those with FP PMA results. Following SP treatment, PMA persisted longer than HRP2, giving an FP diagnosis of P. vivax in up to 16% of patients on day 14, with all FP P. vivax diagnoses having gametocytemia. In contrast, PMA was rapidly cleared following ART + SP treatment in association with rapid clearance of gametocytemia. Gametocytes appear to be an important cause of persistent posttreatment panmalarial antigenemia in areas of endemicity and may also contribute in part to persistent HRP2 antigenemia following treatment.

Primary appendiceal malignancy mimicking advanced stage ovarian carcinoma: a case series.

BACKGROUND: Primary appendiceal malignancy metastatic to the ovaries is a rare condition that may mimic late stage ovarian cancer. This condition is rarely diagnosed preoperatively. CASES: Three patients referred to our institution from 1994 to 1999 for presumed late stage ovarian cancer were found to have primary appendiceal adenocarcinoma, adenocarcinoid, and mucinous cystadenocarcinoma metastatic to the ovaries at laparotomy. We describe the clinical course of these patients and review the relevant literature. CONCLUSION: It is important for the gynecologic oncologist to be aware of the clinicopathological features and surgical management of these malignancies, as the incidence, prognosis, and recommended treatment vary with histological subtype.

Medical management of interstitial pregnancy with a retained IUD. A case report.

BACKGROUND: Systemic methotrexate therapy for interstitial pregnancy has an increased failure rate as compared to other ectopic locations. No case of interstitial pregnancy with a retained intrauterine device (IUD) has been reported on before. CASE: An asymptomatic, 21-year-old woman presented with a positive pregnancy test and a retained IUD. Vaginal ultrasound revealed a left interstitial pregnancy. Diagnostic laparoscopy was followed by a single dose of methotrexate (50 mg/m2). Five days later, a marked increase in the human chorionic gonadotropin level was followed by a second course (four doses) of methotrexate, 1 mg/kg, alternating with 0.1 mg/kg of leucovorin. Concomitant Chlamydia was treated with azithromycin, and the IUD was expelled spontaneously. CONCLUSION: Medical management of interstitial pregnancy may prevent surgery that limits future fertility, but the evidence suggests that more than one dose of methotrexate may be required.

Endocervical curettage when colposcopic examination is satisfactory and normal.

OBJECTIVE: To estimate the incidence of endocervical dysplasia in women with cervical cytology of atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (SIL) who have a satisfactory and normal colposcopic examination. METHODS: An electronic colposcopy database was reviewed and women with satisfactory colposcopic examinations and original cervical cytology of ASCUS on two consecutive Papanicolaou smears, ASCUS favor SIL, or low-grade SIL were selected. Exclusion criteria were pregnancy, insufficient endocervical curettage (ECC), or colposcopic examination that showed an abnormality that required cervical biopsy. Subjects also were excluded if they were postmenopausal or had surgical or ablative therapy for cervical dysplasia within the past year. A computerized review of 2517 patient records found 860 that met the search criteria. A manual review of those records using the exclusion criteria isolated a study group of 159 women. RESULTS: Four of 159 subjects (2.5%, 95% confidence interval [CI] 0.69, 6.3) had dysplastic cells in endocervical curettings. In these four, the ECC specimens had benign endocervical cells and separate fragments of squamous cells with mild dysplasia. In three women, loop electrosurgical excision procedures showed mild dysplasia limited to the transformation zone. The fourth subject was believed to have contamination from an unrecognized ectocervical lesion and was treated conservatively. A repeat ECC found benign endocervical cells. Involvement of the endocervix by dyplasia was excluded in all but one of 159 patients (0.63%, 95% CI 0.02, 3.5). CONCLUSION: Incidence of endocervical dysplasia was extremely low in women with cervical cytology of consecutive ASCUS, ASCUS favor SIL, or low-grade SIL who have a satisfactory and normal colposcopic examination. Our findings suggest that endocervical curettage might be safely avoided in those women.

Genetically distinct dog-derived and human-derived Sarcoptes scabiei in scabies-endemic communities in northern Australia.

Overcrowding is a significant factor contributing to endemic infection with Sarcoptes scabiei in human and animal populations. However, since scabies mites from different host species are indistinguishable morphologically, it is unclear whether people can be infected from scabies-infested animals. Molecular fingerprinting was done using three S. scabiei-specific single locus hypervariable microsatellite markers, with a combined total of 70 known alleles. Multilocus analysis of 712 scabies mites from human and dog hosts in Ohio, Panama and Aboriginal communities in northern Australia now shows that genotypes of dog-derived and human-derived scabies cluster by host species rather than by geographic location. Because of the apparent genetic separation between human scabies and dog scabies, control programs for human scabies in endemic areas do not require resources directed against zoonotic infection from dogs.

Crusted scabies: A molecular analysis of Sarcoptes scabiei variety hominis populations from patients with repeated infestations.

Crusted scabies is a severe debilitating disease due to hyperinfestation with the ectoparasite Sarcoptes scabiei. Treatment protocols include oral ivermectin and topical scabicides. After single-dose ivermectin, there may be early recrudescence, whereas after 3 doses at 14-day intervals, there is an apparent cure. However, such patients often present again after 6-12 months. To clarify the biology of recurrence, we studied genetic markers in sequential populations of S. scabiei mites from treated patients with multiple episodes of crusted scabies. Individual mites were genotyped at hypervariable microsatellite loci by a fluorescence-based polymerase chain reaction. Results indicated that sequential populations of mites were genetically more similar to each other than to mites from other patients. Although the majority of recurrent scabies is probably due to reinfestation from inadequately treated contacts, there was evidence that in very severe crusted scabies, treatment with even 3 doses of ivermectin 14 days apart may be inadequate and relapse may occur.