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J H Oliver

Publications and source records attributed to J H Oliver.

At least 37 records · Page 2Linked to original sources
PubMed2000

Prognostic significance of arterial phase CT for prediction of response to transcatheter arterial chemoembolization in unresectable hepatocellular carcinoma: a retrospective analysis.

OBJECTIVE: The purpose of this study was to use hepatic arterial phase helical CT to assess tumor vascularity and predict the likelihood of response to transcatheter arterial chemoembolization in patients with hepatocellular carcinoma. MATERIALS AND METHODS: Helical CT findings for 57 patients with hepatocellular carcinoma were classified into one of three patterns of vascularity on the basis of the degree of tumor or liver enhancement during the hepatic arterial phase. Cases in which hypervascular lesions predominated were classified as a type 1 pattern. Cases in which hypovascular lesions predominated were classified as a type 2 pattern. Patients were classified as responders or nonresponders on the basis of the changes of tumor size revealed on CT after three transcatheter arterial chemoembolization treatments. RESULTS: We classified the 57 patients as 37 responders (65%) and 20 nonresponders (35%). A statistically significant correlation between the type 1 hypervascular pattern and response to transcatheter arterial chemoembolization was seen; conversely, the type 2 hypovascular pattern correlated with nonresponse to transcatheter arterial chemoembolization (chi-square = 7.85, p = 0.02). Patients classified as responders lived significantly longer than those classified as nonresponders with 12-, 24-, and 36-month survival rates of 90%, 67%, and 36%, respectively, for responders and 70%, 17%, and 10%, respectively, for nonresponders. CONCLUSION: We found that patients who responded to transcatheter arterial chemoembolization had prolonged survival (p < 0.01). Response correlated closely with tumor vascularity as shown on hepatic arterial phase helical CT.

Antineoplastic Agents↗
PubMed2000

Detection of vascular complications after liver transplantation: early experience in multislice CT angiography with volume rendering.

OBJECTIVE: Our objective was to investigate the usefulness of three-dimensional multislice CT angiography for the evaluation of liver transplant recipients presenting with clinical or sonographic findings suggestive of hepatic vascular complications. CONCLUSION: Our early results indicate that three-dimensional multislice CT angiography with volume rendering can reveal common and potentially lethal vascular complications in patients who have undergone liver transplantation.

Aneurysm↗
PubMed2000

Winter ectoparasites of mammals in the northeastern piedmont area of Georgia.

Twenty-three species of ectoparasites were recovered from 10 species of mammals (89 individuals) in Mistletoe State Park, Columbia County, Georgia, during three winter months of 1998. The collection consisted of 9 species of fleas, 6 mites, 4 sucking lice, 3 ticks, and 1 mammal-associated beetle. Some rarely-collected arthropods were recorded including the ctenophthalmid fleas, Doratopsylla blarinae C. Fox and Epitedia cavernicola Traub, the laelapid mite, Echinonyssus blarinae (Herrin) (first records from Georgia for these three ectoparasites), and the leptinid beetle, Leptinus orientamericanus Peck (second record for Georgia). Varying degrees of host-specificity were exhibited by the 23 species of ectoparasites. Because relatively few mammal ectoparasite surveys are completed during the winter months, some seemingly rare species may, in reality, be more common at this time of year.

Animals↗
PubMed2000

Rodent ectoparasites from two locations in northwestern Florida.

From Feb.-Apr. 1999, 19 species of ectoparasitic arthropods (2 sucking lice, 4 fleas, 4 ticks, 2 mesostigmatid mites, 5 chiggers, 2 fur mites) were recovered from 106 rodents belonging to 5 species (cotton mouse, Peromyscus gossypinus, n = 64; cotton rat, Sigmodon hispidus, n = 23; eastern woodrat, Neotoma floridana, n = 9; golden mouse, Ochrotomys nuttalli, n = 9; eastern gray squirrel, Sciurus carolinensis, n = 1) at Tall Timbers Research Station, Leon County, Florida. During the same period, 13 species of ectoparasites (2 sucking lice, 1 flea, 3 ticks, 3 mesostigmatid mites, 2 chiggers, 2 fur mites) were recovered from 57 rodents belonging to 3 species (S. hispidus, n = 40; black rat, Rattus rattus, n = 16; S. carolinensis, n = 1) from Panama City, Bay County, Florida. Noteworthy ectoparasite records include Ixodes minor from both sites, which extends the known geographical range of this tick, and Stenoponia americana from Tall Timbers that represents the second documented Florida record of this flea. Potential tick vectors (Dermacentor variabilis and Ixodes scapularis) of zoonotic pathogens (Rickettsia rickettsii and Borrelia burgdorferi) were collected at both sites. On S. hispidus, fleas were more prevalent at Tall Timbers but sucking lice, chiggers, ticks, mesostigmatid and listrophorid mites all were more prevalent at the Panama City site. Arthropods recovered from arboreal nests (n = 3) of O. nuttalli at Tall Timbers included 3 species of ectoparasites (1 tick, 2 laelapid mites).

Animals↗
PubMed1999

Solitary erythema migrans in Georgia and South Carolina.

OBJECTIVE: To evaluate the incidence of Borrelia burgdorferi infection in humans with erythema migrans (EM) in 2 southeastern states. DESIGN: Prospective case series. SETTING: Family medicine practice at academic center. PATIENTS: Twenty-three patients with solitary EM lesions meeting Centers for Disease Control and Prevention (CDC) criteria for Lyme disease. INTERVENTIONS: Patients underwent clinical and serologic evaluation for evidence of B burgdorferi infection. All lesions underwent photography, biopsy, culture and histopathologic and polymerase chain reaction analysis for B burgdorferi infection. Patients were treated with doxycycline hyclate and followed up clinically and serologically. MAIN OUTCOME MEASURES: Disappearance of EM lesions and associated clinical symptoms in response to antibiotic therapy; short-term and follow-up serologic assays for diagnostic antibody; growth of spirochetes from tissue biopsy specimens in Barbour-Stoenner-Kelly II media; special histopathologic stains of tissue for spirochetes; and polymerase chain reaction assays of tissue biopsy specimens for established DNA sequences of B burgdorferi. RESULTS: The EM lesions ranged from 5 to 20 cm (average, 9.6 cm). Five patients (22%) had mild systemic symptoms. All lesions and associated symptoms resolved with antibiotic therapy. Overall, 7 patients (30%) had some evidence of B burgdorferi infection. Cultures from 1 patient (4%) yielded spirochetes, characterized as Borrelia garinii, a European strain not known to occur in the United States; 3 patients (13%) demonstrated spirochetallike forms on special histologic stains; 5 patients (22%) had positive polymerase chain reaction findings with primers for flagellin DNA sequences; and 2 patients (9%) were seropositive for B burgdorferi infection using recommended 2-step CDC methods. No late clinical sequelae were observed after treatment. CONCLUSIONS: The EM lesions we observed are consistent with early Lyme disease occurring elsewhere, but laboratory confirmation of B burgdorferi infection is lacking in at least 16 cases (70%) analyzed using available methods. Genetically variable strains of B burgdorferi, alternative Borrelia species, or novel, uncharacterized infectious agents may account for most of the observed EM lesions.

Adult↗
PubMed1999

Hepatobiliary malignancies. Primary hepatic malignant neoplasms.

Primary hepatic tumors are epithelial, mesenchymal, or mixed in origin. Of these, epithelial tumors are the most common and include hepatocellular carcinoma, cholangiocarcinoma, mixed hepatocholangiocarcinoma, hepatoblastoma, and a variety of more rare tumors. Hepatocellular carcinoma, also know as hepatoma or malignant hepatoma, is the most common, followed by cholangiocarcinoma. This article discusses these two malignancies.

Carcinoma, Hepatocellular↗
PubMed1999

Ticks and antibodies to Borrelia burgdorferi from mammals at Cape Hatteras, NC and Assateague Island, MD and VA.

Results of a survey for ixodid ticks and/or serum antibodies to Borrelia burgdorferi from 14 species of small to large mammals from eastern coastal areas of the United States are presented. Most samples were obtained from July 1987 through June 1989 (excluding December-March) at 3 locales: Assateague Is. National Seashore, Worcester Co., MD., and Accomack Co., VA. (approximately 38 degrees 05' N 75 degrees 10' W), and Cape Hatteras National Seashore, Dare Co., NC (approximately 35 degrees 30' N 76 degrees 35' W). Hosts sampled included opossums (Didelphis virginiana), least shrews (Cryptotis parva), gray foxes (Urocyon cinereoargenteus), red foxes (Vulpes vulpes), raccoons (Procyon lotor), feral cats (Felis sylvestris), feral horses (Equus caballus), sika deer (Cervus nippon), rice rats (Oryzomys palustris), white-footed mice (Peromyscus leucopus), meadow voles (Microtus pennsylvanicus), house mice (Mus musculus), norway rats (Rattus norvegicus) and jumping mice (Zapus hudsonius). An indirect fluorescent antibody test was used for testing sera from opossums, raccoons, and feral cats; enzyme-linked immunosorbent assays were used for sera from foxes, horses, deer, and house and white-footed mice. Antibodies to B. burgdorferi were found in all species tested from each locale. Seasonal data reinforce the contention that P. leucopus is a suitable sentinel species for B. burgdorferi. Ticks on hosts included Ixodes scapularis Say, I. texanus Banks, Dermacentor variabilis (Say), D. albipictus (Packard), and Amblyomma americanum (L.). Males comprised approximately 0-22 and 60-81% of Ixodes sp. and Amblyomma-Dermacentor adults collected from hosts, respectively. All stages of A. americanum, adult D. variabilis, and larval I. scapularis were collected from vegetation. The highest seropositivity rate (67%) was recorded for 45 P. leucopus at Assateague during July, approximately 1 mo. after peak nymphal I. scapularis intensity. Borrelia burgdorferi was isolated from 6 nymphal and 12 female I. scapularis collected from P. leucopus and C. nippon, respectively, on Assateague.

Animals↗
PubMed1999

Seasonal activity and host associations of Ixodes scapularis (Acari: Ixodidae) in southeastern Missouri.

Based on tick collections recovered from wild vertebrates and by dragging, the seasonal occurrence of adult blacklegged ticks, Ixodes scapularis Say, extended from October through May in southeastern Missouri. Adult activity was bimodal with the higher peak occurring in November followed by a lower peak in February. The activity of immature I. scapularis had the general pattern of that found in the Northeast where Lyme disease is hyperendemic, with larval activity (July) peaking after that of nymphs (May and June). Vertebrates varied in their importance as hosts of I. scapularis. White-tailed deer, Odocoileus virginanus (Zimmerman), and coyotes, Canis latrans Say, were the primary hosts of adult I. scapularis. Broad-headed skinks, Eumeces laticeps (Schneider), and eastern fence lizards, Sceloporus undulatus (Latreille), were the primary hosts of nymphal I. scapularis. The broad-headed skink, 5-lined skink, Eumeces fasciatus (L.), and Carolina wren, Thryothorus ludovicianus (Latham), were the primary hosts of larval I. scapularis. Homeotherms were important hosts of immature I. scapularis, accounting for 30% of nymphs and 39% of larvae collected. The eastern cottontail rabbit, Sylvilagus floridanus (Allen), may play an important role in the epidemiology of Lyme disease in Missouri. Isolates of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner were made from ticks recovered from rabbits, making the cottontail rabbit a key species for further study of the epidemiology of Lyme borreliosis in Missouri.

Animals↗
PubMed1999

End-stage primary sclerosing cholangitis: CT findings of hepatic morphology in 36 patients.

PURPOSE: To determine if there is a significant difference in the hepatic morphology depicted on computed tomographic (CT) scans in patients with end-stage cirrhosis caused by primary sclerosing cholangitis versus that in patients with end-stage cirrhosis caused by other factors. MATERIALS AND METHODS: The frequency of five morphologic findings of the liver parenchyma and two intrahepatic biliary findings identified on CT scans in 36 patients with end-stage cirrhosis caused by primary sclerosing cholangitis were compared with the frequency of the same findings in 472 patients with end-stage cirrhosis caused by other factors. The morphologic findings were lobulation of the liver contour, atrophy of the lateral or posterior hepatic segments, hypertrophy of the caudate lobe, and pseudotumor of the caudate lobe. Lobulation, atrophy, and hypertrophy were subclassified as mild-moderate or severe. The biliary findings were ductal dilatation and calculi. RESULTS: Each of the 11 findings occurred more frequently (P < .05) in patients with primary sclerosing cholangitis than in the other 472 patients. Six findings occurred more frequently (P < .05) in patients with primary sclerosing cholangitis than in patients with cirrhosis caused by any other single agent. CONCLUSION: There is a significant difference in the hepatic morphology observed in patients with primary sclerosing cholangitis-induced end-stage cirrhosis versus that in patients with end-stage cirrhosis of other causes.

Adolescent↗
PubMed1999

Spectrum of imaging findings of the liver in end-stage cirrhosis: Part II, focal abnormalities.

Cirrhosis, through the process of necrosis, fibrosis, regeneration, and malignant transformation, creates multiple focal benign and malignant hepatic masses. The detection and appearance of these masses varies with the severity of the cirrhotic process and the imaging technique used. Although some overlap exists in the imaging appearance of the benign and malignant masses, in most instances recognition of a few characteristic features will yield the correct diagnosis.

Carcinoma, Hepatocellular↗
PubMed1999

Antibodies to granulocytic ehrlichiae in white-footed and cotton mice in eastern United States.

Serum samples, collected from Peromyscus leucopus (white-footed mouse) or Peromyscus gossypinus (cotton mouse) during 1987 through 1990 in Florida, Georgia, Maryland, Mississippi, and North Carolina (USA), and in 1997 in southern Connecticut were analyzed by indirect fluorescent antibody (IFA) staining methods or Western blot procedures for antibodies to granulocytic ehrlichiae. Of the 82 sera from white-footed mice in Connecticut tested by IFA methods with either the BDS or NCH-1 strain of the human granulocytic ehrlichiosis (HGE) agent, 45 (55%) and 42 (51%) of the samples contained antibodies to these strains, respectively, at concentrations ranging from 1:80 to 1:2560. One (2%) of 43 sera from P. leucopus captured in Assateague Island (Maryland) had a titer of 1:80, while three (20%) of 15 sera from P. gossypinus, captured in Sapelo Island (Georgia) and four (40%) of 10 sera from cotton mice caught in Amelia Island (Florida) had antibodies to the NCH-1 strain at titers of 1:160 to 1:1,280. Fifty-five sera from P. leucopus in Cape Hatteras (North Carolina) and 30 sera from P. gossypinus in Mississippi were negative. Western blot analyses confirmed seropositivity for 19 (95%) of 20 mouse sera positive by IFA staining methods, including samples from both mouse species captured in Connecticut, Maryland, or Florida. There were key banding patterns to proteins having molecular masses of about 44, 80, 105, 110, or 120 kDa. Both serologic assays can be used to determine if mice have been exposed to granulocytic ehrlichiae. These rodents also may be useful in surveillance programs to identify endemic sites for HGE and in performing laboratory studies on immune responses to the etiologic agent.

Animals↗
PubMed1999

Investigation of venereal, transplacental, and contact transmission of the Lyme disease spirochete, Borrelia burgdorferi, in Syrian hamsters.

A hamster was inoculated with the SI-1 strain of Borrelia burgdorferi and subsequently served as a host to larval Ixodes scapularis Say. Approximately 68% of the nymphs resulting from the fed larvae were infected. Nymphs from this group were fed on uninfected hamsters, and 3 of 4 males and 6 of 6 females became infected. The infected hamsters were allowed to mate with uninfected partners to test for venereal transmission. Six infected females were mated with 6 uninfected males, whereas 3 infected males were mated with 6 uninfected females. None of the uninfected hamsters became infected after mating. Two protocols were used to determine if transplacental transmission of B. burgdorferi occurred. One group included 6 nonpregnant infected females that were subsequently mated and became pregnant. Three of the females were allowed to carry to full term, whereas the other 3 were killed prior to parturition. All fetuses and offspring were negative for B. burgdorferi based on cultures and monoclonal antibody assays. Another group of 6 females was infected via tick bite after becoming pregnant; those females were allowed to carry fetuses to birth and all were negative. Attempts at contact transmission of B. burgdorferi from 2 infected females to 2 uninfected male and 2 uninfected female hamsters and from 2 infected males to 2 uninfected male and uninfected female hamsters via urine or feces failed.

Animals↗
PubMed1998

The question of fluctuating asymmetry in the blacklegged tick Ixodes scapularis (Acari: Ixodidae).

An analysis of fluctuating asymmetry was conducted on populations of the blacklegged tick Ixodes scapularis. The eight groups used in this study consisted of larvae and nymphs and males and females from the states of Minnesota, Massachusetts, Maryland, Missouri, North Carolina and Georgia and the F1 progenies of reciprocal crosses between ticks from Massachusetts and Georgia. Measurements included 16 larval, 19 nymphal, ten female and 12 male bilateral characters. Only five differences between the right and left bilateral characters had normal distributions with means of zero and differences in variances between the groups. These five characters included three setal lengths of the larvae, the spiracular plate length of females and the coxa I internal spur widths of males. Bivariate plots of character size ((R + L)/2) and asymmetry (R-L) showed no correlation. In the spiracular plate lengths of females and one of the setal lengths, ticks from Massachusetts had significantly less within-group variance than all the other groups. The only character in which fluctuating asymmetry was observed was the coxa I internal spur width of males, in which ticks from Minnesota, Missouri and North Carolina had significantly greater variance than the remaining groups; fluctuating asymmetry in this character may be explained by sexual selection. The cross progeny did not demonstrate any fluctuating asymmetry, as would be expected if the northern and southern forms of I. scapularis were true species. The virtual lack of fluctuating asymmetry in the characters used in this study further supports the conclusions of other studies which concluded that I. scapularis is a species with clinical variation and a broad geographic distribution.

Animals↗
PubMed1998

Laboratory life cycle of Ixodes woodi (Acari: Ixodidae).

A 24-mo study of the laboratory life cycle of the tick Ixodes woodi Bishopp was conducted. No other such study of any species in the subgenus Ixodiopsis Filippova has been reported. Three generations of I. woodi were examined. Larvae and nymphs fed for an average of 4 d; approximately 8-9 d were required for females to engorge. Females laid approximately 900 eggs that required an average of 37.33 d to hatch.

Animals↗
PubMed1998

Life cycle of Ixodes minor (Acari: Ixodidae) in the laboratory.

Details of the laboratory life cycle of 3 generations of Ixodes minor Neumann were recorded. Larvae and nymphs were fed on white laboratory mice and adults were fed on woodrats. Nymphs fed for 4 d and larvae for an average of 4 d; approximately 10 to 11 d were required for females to engorge. After feeding, females laid approximately 1,600 eggs that required an average of 39.7 d to hatch. Eggs were maintained at 97.5% RH and approximately 25 degrees C as were all stages of the ticks when not feeding. The life cycle in the laboratory required approximately 180 d; however, in nature it probably takes longer. I. minor has been recorded from several rodent and bird species known to be infected with Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt & Brenner). This study provides data on the life cycle of a potential enzootic tick vector of this spirochete.

Animals↗
PubMed1998

First isolation and cultivation of Borrelia burgdorferi sensu lato from Missouri.

Five Borrelia burgdorferi sensu lato isolates from Missouri are described. This represents the first report and characterization of such isolates from that state. The isolates were obtained from either Ixodes dentatus or Amblyomma americanum ticks that had been feeding on cottontail rabbits (Sylvilagus floridanus) from a farm in Bollinger County, Mo., where a human case of Lyme disease had been reported. All isolates were screened immunologically by indirect immunofluorescence by using monoclonal antibodies to B. burgdorferi-specific outer surface protein A (OspA) (antibodies H3TS and H5332), B. burgdorferi-specific OspB (antibody H6831), Borrelia (genus)-specific antiflagellin (antibody H9724), and Borrelia hermsii-specific antibody (antibody H9826). Analysis of the isolates also involved a comparison of their protein profiles by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Finally, the isolates were analyzed by PCR with six pairs of primers known to amplify selected DNA target sequences specifically found in the reference strain B. burgdorferi B-31. Although some genetic variability was detected among the five isolates as well as between them and the B-31 strain, enough similarities were found to classify them as B. burgdorferi sensu lato.

Animals↗
PubMed1998

Distribution, abundance, and seasonal activities of ticks collected from rodents and vegetation in South Carolina.

Ixodid ticks were collected from live-trapped rodents and by flagging vegetation at sites in the Piedmont, Sandhills, Coastal Plain, and Coastal Zone of South Carolina from May 1994 through December 1995. A total of 1,514 ticks was recovered from 237 live-trapped rodents. Host-attached species included Ixodes minor Neumann (n = 818), Dermacentor variabilis (Say) (n = 346), Amblyomma maculatum Koch (n = 209), Ixodes affinis Neumann (n = 89), and Ixodes scapularis Say (n = 52). Species of questing adult ticks collected from vegetation were Ix. scapularis (n = 1,627), Amblyomma americanum L. (n = 1,052), D. variabilis (n = 649), A. maculatum (n = 134), Ix. affinis (n = 70), and Dermacentor albipictus (Packard) (n = 3). Geographic distribution and seasonal activities of most stages and species are presented. This report includes the first detailed description of the seasonal activities of all active stages of Ix. minor in the United States, and documents that this tick is well established in the southern Coastal Zone of South Carolina.

Animals↗