Molecular Characterization of Sweet potato feathery mottle virus (SPFMV) Isolates from Easter Island, French Polynesia, New Zealand, and Southern Africa.

Strains of Sweet potato feathery mottle virus (SPFMV; Potyvirus; Potyviridae) infecting sweet-potato (Ipomoea batatas) in Oceania, one of the worlds' earliest sweetpotato-growing areas, and in southern Africa were isolated and characterized phylogenetically by analysis of the coat protein (CP) encoding sequences. Sweetpotato plants from Easter Island were co-infected with SPFMV strains C and EA. The EA strain isolates from this isolated location were related phylogenetically to those from Peru and East Africa. Sweetpotato plants from French Polynesia (Tahiti, Tubuai, and Moorea) were co-infected with SPFMV strains C, O, and RC in different combinations, whereas strains C and RC were detected in New Zealand. Sweetpotato plants from Zimbabwe were infected with strains C and EA and those from Cape Town, South Africa, with strains C, O, and RC. Co-infections with SPFMV strains and Sweet potato virus G (Potyvirus) were common and, additionally, Sweet potato chlorotic fleck virus (Carlavirus) was detected in a sample from Tahiti. Taken together, occurrence of different SPFMV strains was established for the first time in Easter Island, French Polynesia, and New Zealand, and new strains were detected in Zimbabwe and the southernmost part of South Africa. These results from the Southern hemisphere reflect the anticipated global distribution of strains C, O, and RC but reveal a wider distribution of strain EA than was known previously.

Molecular Genetic Characterization of Sweet potato virus G (SPVG) Isolates from Areas of the Pacific Ocean and Southern Africa.

Sweet potato virus G (SPVG, genus Potyvirus, family Potyviridae) was detected in sweetpotato (Ipomoea batatas) storage roots sold in the local markets and storage roots or cuttings sampled directly from farmers' fields. Using serological and molecular methods, the virus was detected for the first time in Java, New Zealand, Hawaii, Tahiti, Tubuai, Easter Island, Zimbabwe, and South Africa, and also in an imported storage root under post-entry quarantine conditions in Western Australia. In some specimens, SPVG was detected in mixed infection with Sweet potato feathery mottle virus (genus Potyvirus). The coat protein (CP) encoding sequences of SPVG were analyzed for 11 plants from each of the aforementioned locations and compared with the CP sequences of 12 previously characterized isolates from China, Egypt, Ethiopia, Spain, Peru, and the continental United States. The nucleotide sequence identities of all SPVG isolates ranged from 79 to 100%, and amino acid identities ranged from 89 to 100%. Isolates of the same strain of SPVG had nucleotide and amino acid sequence identities from 97 to 100% and 96 to 100%, respectively, and were found in sweetpotatoes from all countries sampled except Peru. Furthermore, a plant from Zimbabwe was co-infected with two clearly different SPVG isolates of this strain. In contrast, three previously characterized isolates from China and Peru were phylogenetically distinct and exhibited <90% nucleotide identity with any other isolate. So far, the highest genetic diversity of SPVG seems to occur among isolates in China. Distribution of SPVG within many sweetpotato growing areas of the world emphasizes the need to determine the economic importance of SPVG.

Detection of prosthetic hip infection at revision arthroplasty by immunofluorescence microscopy and PCR amplification of the bacterial 16S rRNA gene.

In this study the detection rates of bacterial infection of hip prostheses by culture and nonculture methods were compared for 120 patients with total hip revision surgery. By use of strict anaerobic bacteriological practice during the processing of samples and without enrichment, the incidence of infection by culture of material dislodged from retrieved prostheses after ultrasonication (sonicate) was 22%. Bacteria were observed by immunofluorescence microscopy in 63% of sonicate samples with a monoclonal antibody specific for Propionibacterium acnes and polyclonal antiserum specific for Staphylococcus spp. The bacteria were present either as single cells or in aggregates of up to 300 bacterial cells. These aggregates were not observed without sonication to dislodge the biofilm. Bacteria were observed in all of the culture-positive samples, and in some cases in which only one type of bacterium was identified by culture, both coccoid and coryneform bacteria were observed by immunofluorescence microscopy. Bacteria from skin-flake contamination were readily distinguishable from infecting bacteria by immunofluorescence microscopy. Examination of skin scrapings did not reveal large aggregates of bacteria but did reveal skin cells. These were not observed in the sonicates. Bacterial DNA was detected in 72% of sonicate samples by PCR amplification of a region of the bacterial 16S rRNA gene with universal primers. All of the culture-positive samples were also positive for bacterial DNA. Evidence of high-level infiltration either of neutrophils or of lymphocytes or macrophages into associated tissue was observed in 73% of patients. Our results indicate that the incidence of prosthetic joint infection is grossly underestimated by current culture detection methods. It is therefore imperative that current clinical practice with regard to the detection and subsequent treatment of prosthetic joint infection be reassessed in the light of these results.

Melorheostosis in a family with autosomal dominant osteopoikilosis.

We describe a 19-year-old woman with melorheostosis and osteopoikilosis (mixed sclerosing bone dysplasia). Her sister and mother had osteopoikilosis, but no evidence of melorheostosis. Isolated melorheostosis and melorheostosis with osteopoikilosis are sporadic disorders. Osteopoikilosis is an autosomal dominant trait. Mixed sclerosing bone dysplasia in a family with autosomal dominant osteopoikilosis raises the possibility that the two bone disorders may be related. This family and that of Butkus et al. [1997: Am J Med Genet 72:43-46] suggest that the melorheostosis could be due to a second mutation at the same locus as that which causes autosomal dominant osteopoikilosis.

Improved detection of infection in hip replacements. A currently underestimated problem.

Our aim was to determine if the detection rate of infection of total hip replacements could be improved by examining the removed prostheses. Immediate transfer of prostheses to an anaerobic atmosphere, followed by mild ultrasonication to dislodge adherent bacteria, resulted in the culture of quantifiable numbers of bacteria, from 26 of the 120 implants examined. The same bacterial species were cultured by routine microbiological techniques from only five corresponding tissue samples. Tissue removed from 18 of the culture-positive implants was suitable for quantitative tissue pathology and inflammatory cells were present in all samples. Furthermore, inflammatory cells were present in 87% of tissue samples taken from patients whose implants were culture-negative. This suggests that these implants may have been infected by bacteria which were not isolated by the techniques of culture used. The increased detection of bacteria from prostheses by culture has improved postoperative antibiotic therapy and should reduce the need for further revision.

Primary synovial chondromatosis: a clinicopathologic review and assessment of malignant potential.

This is a clinicopathologic review of 53 cases of primary synovial chondromatosis covering a period of 30 years. The average age at presentation was 41 years (range, 17 to 64 years) with a male/female preponderance of 1.8:1. The condition was always monarticular, the most common site being the knee joint (70%) followed by the hip (20%). Degenerative joint disease was well established in three patients (5%), all occurring in the hip. Nine patients suffered recurrences (15%), including three that became malignant. There was no relationship between the age and site of the lesion, nor between the degree of cellularity of the cartilage and age or site. However, there was an association between cellularity of the cartilage and the extent of calcification and ossification--highly cellular lesions were poorly calcified and ossified, but heavily calcified lesions were usually of relatively low cellularity. There was no relationship between extent of calcification and ossification and the age of the patient. Three patients suffered malignant change representing a relative risk of 5%, much higher than that quoted in other series. This suggests that primary synovial chondromatosis has a significant potential for malignant change.

Cell proliferation studies in primary synovial chondromatosis.

Primary synovial chondromatosis (PSC) is thought to be a cartilaginous metaplasia, but it may recur locally and malignant change has been reported. Histologically, the cartilage is usually cellular, with binucleate forms. These findings suggest that the disease is not simply a metaplasia but imply a proliferative component. In this study, immunohistochemical detection of Ki-67 protein using an antigen retrieval microwave heating technique and DNA image cytometry (VIDAS image analysis system) has been used to assess the proliferative activity in 20 cases of PSC and the results have been compared with those obtained in other cartilage tissues: ten enchondromas, ten chondrosarcomas, and ten samples of normal articular cartilage. There was no detectable staining for Ki-67 protein in cases of PSC or in benign tissues, but there was a significant association between Ki-67 labelling index and grade in the chondrosarcomas (P < 0.01). The absence of mitotic figures and the lack of Ki-67 protein in PSC are consistent with a metaplasia. All enchondromas gave diploid DNA histograms but non-diploid histograms were obtained i eight cases (40 per cent) of PSC, with significant populations of hyperdiploid and DNA aneuploid cells. The mean DNA content, the percentage of hyperdiploid cells, the percentage of DNA aneuploid cells, and the 2c deviation index were all significantly higher in PSC than in enchondromas (P < 0.01). These findings with image cytometry suggest a proliferative process in the development of at least some cases of PSC. In terms of cell proliferative activity, PSC appears to occupy a position which is intermediate between benign enchondromas and malignant chondrosarcomas, which may explain the aggressive clinical behaviour occasionally seen in this condition.

C-erb B-2 staining in primary synovial chondromatosis: a comparison with other cartilaginous tumours.

In this study C-erb B-2 immunostaining has been used to highlight distinct differences between the cartilage found in primary synovial chondromatosis (n = 20), normal articular cartilage (n = 10), benign enchondromas (n = 10), and chondrosarcomas (n = 10). There was no positive staining in either the normal cartilage or the chondromas, but 15 cases of synovial chondromatosis showed at least some staining, although in the majority of cases fewer than 50 per cent of cells stained positive. There was no correlation between cellularity/pleomorphism and the extent or intensity of staining. Five of the chondrosarcomas were positive, with more than 50 per cent of cells showing positive staining in three of these cases. All positive cases in this series showed a diffuse cytoplasmic staining pattern. Despite these results, there was no Ki-67 positive staining in synovial chondromatosis, which tends to suggest that the demonstrated expression of C-erb B-2 is not related to proliferative activity. The significance of this staining remains undetermined.

Hearing threshold shifts from repeated 6-h daily exposure to impact noise.

Exposure of chinchillas to broadband, high-level impact noise on an interrupted 6-h daily schedule over 20 days has shown that pure-tone thresholds measured immediately following each daily exposure improve as much as 30 dB despite the continuing noise exposure. The time constant of this recovery effect (toughening) and the magnitude of the effect are related to the audiometric test frequency and the exposure energy. The trauma, quantified by permanent threshold shifts and sensory cell losses, produced by the interrupted exposure paradigm is generally less than that produced by an equal-energy uninterrupted exposure. The wide variations in the temporal pattern of threshold shift across similarly exposed animals suggest that the toughening effect reflects the underlying susceptibility of that animal to noise trauma.

The role of tuning curve variables and threshold measures in the estimation of sensory cell loss.

Auditory-evoked potential tuning curves were collected at six frequencies before and 30 days after various noise exposures in 363 chinchillas using a simultaneous masking paradigm. Traditional bivariate and multiple linear regression/correlation analyses were performed in an effort to determine the extent to which sensory cell damage could be estimated from a knowledge of audiometric and tuning curve variables. The results showed strong correlations between percent outer hair cell (%OHC) loss and permanent threshold shift (PTS) and between %OHC loss and the tuning curve variables Q10 dB and high- and low-frequency slopes (SHF, SLF). The correlations were strongest between PTS and %OHC loss. However, the proportion of variability (r2) in %OHC loss attributable to variability in the predictor variable(s) (i.e., PTS) could be increased significantly by adding the Q10 dB of the tuning curve whose probe frequency was centered in the octave band length of the cochlea corresponding to the frequency at which the PTS occurred. The r2 values could be further increased by including audiometric and tuning curve variables from frequencies adjacent to the octave band being evaluated.

Carcinoembryonic antigen (CEA) in benign and malignant epithelium of the gall bladder, extrahepatic bile ducts, and ampulla of Vater.

Carcinoembryonic antigen (CEA) has been reported in benign and malignant epithelium of the gall bladder, although cross-reactivity with CEA-related antigens cannot be excluded. We have investigated the immunoreactivity of three monoclonal and two polyclonal antisera to CEA in benign and malignant epithelium of the gall bladder, extrahepatic bile ducts, and ampulla of Vater. The results varied with the antisera, due to cross-reactivity with CEA-related antigens and according to the epitope specificities. Little CEA was found in benign epithelium using monoclonal antisera or following absorption of a polyclonal antiserum from Dako with human liver powder. The latter was the most reliable at detecting malignant epithelium of the gall bladder and extrahepatic bile ducts. All antisera showed equal immunoreactivity in tumours of the ampulla of Vater. The differences seen in the immunoreactivities between tumours of the upper and lower extrahepatic biliary tract probably indicate a variation in the occurrence of CEA epitopes.

Audiometric and histological differences between the effects of continuous and impulsive noise exposures.

An experiment was designed to determine if, for equal SPL and power spectrum, the effects on hearing of high-kurtosis noise exposures and a Gaussian noise exposure are different and the extent to which any differences measured in terms of audiometric and histological variables are frequency specific. Three groups of chinchillas with 10 animals/group were exposed for 5 days at 90 dB SPL to one of three types of noise, each with the same power spectrum. The impulsiveness, defined by the kurtosis, and the region of the spectrum from which the impulsive components of the noise were created differed for two of the noises, while the third was a continuous Gaussian noise. The results show that the most impulsive noise produced up to 20 dB greater permanent threshold shift at the high frequencies than did the Gaussian noise exposure. However, these audiometric results were difficult to reconcile with the pattern of sensory cell losses that showed statistically significant larger losses of outer hair cells for the impulsive exposure in the 0.25-kHz region. When the impacts in a high-kurtosis noise were created from the energy in the 1- through 6-kHz region of the spectrum, the audiometric profile of hearing loss was similar to that produced by the Gaussian noise; however, inner hair cell losses were significantly greater in the 4-kHz octave band region of the cochlea.

Complex noise exposures: an energy analysis.

Industrial noise environments usually present a complex stimulus to the exposed individual. These environments often contain mixtures of multiply reflected impact noises and a relatively Gaussian broadband noise. Noise exposure standards do not consider the possibility of interactions between the two classes of noise that can exacerbate the amount of hearing trauma. This paper presents the results of a large series of experiments designed to document the hazard posed to hearing from complex noise exposures. Twenty-three groups of chinchillas with 5 to 11 animals per group (total N = 135) were exposed for 5 days to either octave bands of noise, impacts alone, or combinations of impact and octave bands of noise. Evoked potential measures of hearing thresholds and cochleograms were used to quantify the noise-induced trauma. The results show that, for sound exposure levels (SEL) which produce less than approximately 10 dB PTS (permanent threshold shift) or 5% total sensory cell loss, equal-energy exposures tend to produce equivalent effects on hearing. However, there is a range of at least 10 dB in the SEL parameter where hearing loss from equal-energy exposures at a particular SEL can be exacerbated by increasing the repetition rate of the impacts or by the addition of a Gaussian low-level noise. The exacerbation of trauma from the addition of a Gaussian continuous noise is dependent upon the spectrum of that noise.

Frequency selectivity in noise-damaged cochleas.

Measures of auditory threshold and masked threshold were obtained at six audiometric test frequencies along with cochleograms on a total population of 363 noise-exposed chinchillas. Seventy animals were chosen from this sample and were separated into five relatively homogeneous groups based upon the amount of permanent threshold shift and sensory cell losses the animals incurred. Tuning curve (TC) metrics were compared to the mean preexposure TC metrics for each group and to the reference preexposure TC metrics obtained from the sample of 363 animals. These data show that in animals with relatively little hearing loss changes in TC metrics can provide evidence for noise-induced sensory cell losses and that the low frequency slope of the TC is a sensitive index of trauma.

Cytogenetic and fluorescence in situ hybridization analysis of breast fibroadenomas.

We report cytogenetic and fluorescence in situ hybridization (FISH) analysis findings in 7 patients with breast fibroadenomas (FA). Three patients were cytogenetically abnormal. One patient had a translocation t(3;5)(p22;q13), the second had trisomy 8, and the third two clones, 47, XX, +11 and 47,XX, +10.