Genetic characterization and diversity of porcine circovirus type 2 in non‐vaccinated South African swine herds

The porcine circovirus type 2 (PCV2) is a swine infectious viral pathogen of great significance in global swine herds. It was recently detected at another Province of South Africa sequel to the first detection of North American‐like strain (PCV2a) at Gauteng about two decades ago, but there is a dearth of information about the genomic features and diversity of the viral strains in circulation within the country and the entire sub‐Saharan Africa region. To date, only one complete genome of the virus from South Africa is available on global data base. This current effort is therefore geared towards the full‐genome characterization of the circulating PCV2 strains in the pigs of Eastern Cape Province. With the use of conventional polymerase chain reaction method, fifteen complete PCV2 genomes were successfully amplified, sequenced and assembled from field samples obtained from non‐vaccinated pigs in the region. Neighbor Joining and Maximum Likelihood phylogenetic analyses of the ORF2 gene and full genomes unanimously showed that most of the assembled genomes (11) belong to genotype PCV2b. Furthermore, three of the characterized sequences formed clade with other reference mutant PCV2b and PCV2b subtype 1C (i.e. PCV2d) strains from the USA, China and South Korea. The last sequence, however, clustered with other reference strains belonging to PCV2 intermediate clade 2 (PCV2‐IM2), recently identified in a global PCV2 strains phylogenetic analysis. This study reports the first complete genome sequences of PCV2b, PCV2d and PCV2‐IM2 in pigs from South Africa, and it gives a possible insight into the genetic characteristics and variability of the viral strains presently in circulation within the country. It further emphasizes the need for more stringent measures in curtailing the introduction and spread of transboundary swine pathogens in the country and entire Southern African region.     

Misdiagnosis of hysteria

The diagnosis of hysteria is often incorrect and must be made with great caution. A retrospective study demonstrates that an erroneous diagnosis of hysteria is most likely to be given to females, the psychiatrically ill, patients who embellish and patients who present plausible psychogenic explanations for their illness. Movement disorders and paralysis are the neurologic disorders most frequently mislabeled as hysteria.     

Fluoridated elastomers: effect on the microbiology of plaque.

The objective of this study was to investigate the effect of fluoridated elastomeric ligatures on the microbiology of local dental plaque in vivo. This randomized, prospective, longitudinal, clinical trial had a split-mouth crossover design. The subjects were 30 patients at the beginning of their treatment with fixed orthodontic appliances in the orthodontic departments of the Liverpool and the Sheffield dental hospitals in the United Kingdom. The study consisted of 2 experimental periods of 6 weeks with a washout period between. Fluoridated elastomers were randomly allocated at the first visit to be placed around brackets on tooth numbers 12, 11, 33 or 22, 21, 43. Nonfluoridated elastomers were placed on the contralateral teeth. Standard nonantibacterial fluoridated toothpaste and mouthwash were supplied. After 6 weeks (visit 2), the elastomers were removed, placed in transport media, and plated on agar within 2 hours. Nonfluoridated elastomers were placed on all brackets for 1 visit to allow for a washout period. At visit 3, fluoridated elastomers were placed on the teeth contralateral to those that received them at visit 1. At visit 4, the procedures at visit 2 were repeated. Samples were collected on visits 2 and 4. A logistic regression was performed, with the presence or absence of streptococcal or anaerobic growth as the dependent variable. A mixed-effects analysis of variance was carried out with the percentage of streptococcal or anaerobic bacterial count as the dependent variable. The only significant independent variables were the subject variable (P =<.001) for the percentage of streptococcal and anaerobic bacterial count and the visit variable for the percentage of streptococcal count (P =<.001). The use of fluoridated or nonfluoridated elastomers was not significant for percentage of either streptococcal (P =.288) or anaerobic count (P =.230). Fluoridated elastomers are not effective at reducing local streptococcal or anaerobic bacterial growth after a clinically relevant time in the mouth.     

Inability to assess breath sounds during air medical transport by helicopter

This study assessed the capabilities of a traditional and an amplified stethoscope used by flight nurses to assess breath sound during air medical transport in an MBB BO-105 helicopter. We developed a normal breath sound model using a prerecorded tape of breath sounds interspersed with segments without breath sounds; the recorder had been placed in the chest wall of a resuscitation training manikin. Flight nurses completed control listening sessions in a quiet environment and experimental sessions during flight using a traditional stethoscope for half of the sessions and an amplified stethoscope for the remaining half. In the quiet environment, flight nurses accurately reported the presence or absence of breath sounds in 110 (92%) of 120 trials. During helicopter flight, none of the flight nurses heard breath sounds during any of the recorded segments with either the traditional stethoscope or the amplified stethoscope. We conclude that flight nurses are unable to hear normal breath sounds using a traditional or amplified stethoscope during flight in a medically configured MBB BO-105 helicopter. Improved stethoscopes, innovative methods of listening, and reduction of aircraft noise are potential solutions to the problems of breath sound assessment during air medical transport.     

A new transthyretin variant (Ser 24) associated with familial amyloid polyneuropathy.

An American kindred with systemic amyloidosis presenting with carpal tunnel syndrome, peripheral neuropathy, and cardiomyopathy is reported. The transthyretin gene of a patient was analysed by direct DNA sequencing and both cytosine and thymine were present at the first base of codon 24. This new point mutation in exon 2 results in the amino acid substitution of serine for proline in the A-B loop of the transthyretin molecule. DNA testing for this mutant allele by restriction fragment length polymorphism analysis based on the polymerase chain reaction is described.     

Flow cytometry in carcinoma of the prostate

Flow cytometry is a quantitative cytologic technique with demonstrated utility in the assessment of prostate cancer as well as other tumors. The authors summarize current data on its use in disease detection and diagnosis, prognostic evaluation, and monitoring of response to therapy. They also project future developments.     

Effects of tamoxifen and somatostatin analogue on growth of human medullary, follicular, and papillary thyroid carcinoma cell lines: tissue culture and nude mouse xenograft studies

The knowledge that (1) the normal thyroid contains somatostatin, (2) polypeptide growth factors influence thyroid cell function, and (3) thyroid cells contain steroid hormone receptors prompted us to add somatostatin analogue No. 201-995 (SMS) (5 ng/ml) and/or tamoxifen citrate (TAM) (5 mumol/L) to 7-day monolayer cultures (50,000 cells/well) of three separate human thyroid carcinoma cell lines: DR081 (medullary), WR082 (follicular), and NPA'87 (papillary). Results, tabulated as cell numbers/well (X10(5) on day 7, revealed that TAM inhibited growth of medullary and follicular cells and that TAM plus SMS inhibited growth of papillary cells. In vivo studies of subcutaneous tumor cell xenografts in nude mice have documented that TAM (5 mg subcutaneous pellet) significantly inhibits the growth of medullary implants. Flow cytometric DNA studies of medullary cell cultures demonstrated a reduced G2 + M phase with TAM treatment. For papillary cell implants, TAM plus SMS (5 micrograms subcutaneously, twice daily) did not suppress tumor growth. All three cell lines were negative for estrogen receptor; addition of estradiol (5 ng/ml) to medullary cell cultures neither stimulated replication nor reversed the inhibitory effects of TAM in vitro. We conclude that (1) TAM slowed the growth of a cell line of human medullary carcinoma, both in vitro and in vivo; (2) this effect was not reversed by estradiol; (3) TAM plus SMS inhibited replication of a papillary carcinoma cell line in vitro, but not in vivo; and (4) TAM alone and TAM plus SMS inhibited replication of cultures of a human follicular thyroid carcinoma cell line. TAM and SMS may be useful in treatment of some human thyroid carcinomas.     

Nonprogression of subclinical beta-cell dysfunction among first-degree relatives of IDDM patients. 5-yr follow-up of the Seattle Family Study

It is unknown among first-degree relatives of individuals with insulin-dependent diabetes mellitus (IDDM) whether the disease process occurs in relatively few but always progresses to clinical IDDM or whether subclinical disease is more common but remains nonprogressive in many cases. Islet cell antibodies (ICAs) were found in 21 of 724 (2.9%) first-degree relatives during screening in the greater Seattle area between 1983 and 1988. Measures of beta-cell function (glucose disappearance rate [Kg], fasting insulin, acute insulin response to intravenous arginine [AIRarg], acute insulin response to intravenous glucose [AIRgluc], slope of glucose potentiation of AIRarg) and insulin sensitivity were obtained. Twenty individuals, 9 ICA+ relatives and 11 ICA- relatives, were evaluated prospectively. When expressed in relation to the expected AIRgluc based on each subject's sensitivity index, AIRgluc in 18 of 20 relatives fell below 100%, indicating inappropriately low insulin secretion (subclinical beta-cell dysfunction). After a median follow-up of 42 mo, 10 of 11 ICA- relatives remained ICA-. None showed deteriorating beta-cell dysfunction, and none developed diabetes. Five ICA+ relatives showed persistent immunologic positivity. beta-Cell function remained remarkably stable in all except 2 relatives. One was a 15-yr-old boy who developed IDDM shortly after screening and before evaluation of beta-cell function could be carried out. The other was an 18-yr-old monozygotic twin who developed IDDM after 27 mo. Both of these individuals had ICAs of 80 Juvenile Diabetes Foundation U and had been discordant for less than 5 yr.(ABSTRACT TRUNCATED AT 250 WORDS)