Physicochemical determinants of pH in pectoralis major of three strains of laying hens housed in conventional and furnished cages.

1. Post-mortem decline in muscle pH has traditionally been attributed to glycogenolysis-induced lactate accumulation. However, muscle pH ([H+]) is controlled by complex physicochemical relationships encapsulated in the Stewart model of acid-base chemistry and is determined by three system-independent variables - strong ion difference ([SID]), total concentration of weak acids ([Atot]) and partial pressure of CO2 (PCO2). 2. This study investigated these system-independent variables in post-mortem pectoralis major muscles of Shaver White, Lohmann Lite and Lohmann Brown laying hens housed in conventional cages (CC) or furnished cages (FC) and evaluated the model by comparing calculated [H+] with previously measured [H+] values. 3. The model accounted for 99.7% of the variation in muscle [H+]. Differences in [SID] accounted for most or all of the variations in [H+] between strains. Greater PCO2 in FC was counteracted by greater sequestration of strong base cations. The results demonstrate the accuracy and utility of the Stewart model for investigating determinants of meat [H+]. 4. The housing differences identified in this study suggested that hens housed in FC have improved muscle function and overall health due to the increased opportunity for movement. These findings support past studies showing improved animal welfare for hens housed in FC compared to CC. Therefore, the Stewart model has been identified as an accurate method to assess changes in the muscle at a cellular level that affect meat quality that also detect differences in the welfare status of the research subjects.

Herpes simplex virus type 2 antibody detection performance in Kisumu, Kenya, using the Herpeselect ELISA, Kalon ELISA, Western blot and inhibition testing.

BACKGROUND: In certain parts of Africa, type-specific herpes simplex virus type 2 (HSV-2) ELISAs may have limited specificity. To date, no study has been conducted to validate HerpeSelect and Kalon type-specific HSV-2 ELISAs using both the Western blot and recombinant gG ELISA inhibition testing as reference standards. METHODS: A total of 120 men who were HIV seronegative (aged 18-24 years) provided blood samples. HSV-2 IgG serum antibodies were detected using four different methods: HerpeSelect HSV-2 ELISA (n = 120), Kalon HSV-2 ELISA (n = 120), University of Washington Western blot (n = 101) and a recombinant inhibition test (n = 93). RESULTS: HSV-2 seroprevalence differed significantly by HSV-2 detection method, ranging from 24.8% with the Western blot to 69.8% with the HerpeSelect ELISA. Using the Western blot as the reference standard, the HerpesSelect had the highest sensitivity for HSV-2 antibody detection (100%) yet lowest specificity (40%). Similar results were obtained using the inhibition test as the reference standard. The sensitivity and specificity of the Kalon test versus the Western blot were 92% and 79%, respectively, and 80% and 82% versus the inhibition test. Using the inhibition test as the reference standard, the sensitivity of the Western blot appeared low (49%). CONCLUSIONS: In men in western Kenya who were HIV seronegative, the HerpeSelect and Kalon type-specific ELISAs had high sensitivities yet limited specificities using the Western blot as reference standard. Overall, the Kalon ELISA performed better than the HerpeSelect ELISA in these young men from Kisumu. Further understanding is needed for the interpretation of HSV-2 inhibition or ELISA test positive/ Western blot seronegative results. Before HSV-2 seropositivity may be reliably reported in selected areas of Africa, performance studies of HSV-2 serological assays in individual geographical areas are recommended.

Possible reasons for an increase in the proportion of genital ulcers due to herpes simplex virus from a cohort of female bar workers in Tanzania.

OBJECTIVES: To determine trends in the prevalence and aetiological distribution of genital ulcer syndrome (GUS) in a cohort of female bar workers and to assess factors associated with these trends. METHODS: An open cohort of 600 women at high risk of HIV and sexually transmitted infection (STI) was offered screening and treatment for STI at 3-month intervals. The prevalence of GUS and associated aetiological agents (Herpes simplex virus (HSV), Treponema pallidum and Haemophilus ducreyi) were monitored over 27 months through clinical examination, dry lesion swabbing and multiplex polymerase chain reaction. The effects of HIV status and other factors on the prevalence trends of STI were assessed. RESULTS: A total of 753 women were recruited into the cohort over 10 examination rounds. At recruitment, the seroprevalence was 67% for HIV and 89% for HSV type 2 (HSV-2). During follow-up, 57% of ulcers had unknown aetiology, 37% were due to genital herpes and 6% to bacterial aetiologies, which disappeared completely in later rounds. The absolute prevalence of genital herpes remained stable at around 2%. The proportion of GUS caused by HSV increased from 22% to 58%, whereas bacterial causes declined. These trends were observed in both HIV-negative and HIV-positive women. CONCLUSIONS: The changes observed in the frequency and proportional distribution of GUS aetiologies suggest that regular STI screening and treatment over an extended period can effectively reduce bacterial STI and should therefore be sustained. However, in populations with a high prevalence of HSV-2, there remains a considerable burden of genital herpes, which soon becomes the predominant cause of GUS. Given the observed associations between genital herpes and HIV transmission, high priority should be given to the evaluation of potential interventions to control HSV-2 either through a vaccine or through episodic or suppressive antiviral therapy and primary prevention.

The effect of limited overfeeding during growth on muscle characteristics: a pig model.

Energy restriction affects the hypothalamus, leading to a decrease in production of reproductive and thyroid hormones. A decrease in reproductive hormones affects fertility and a decrease in thyroid hormones affects muscle metabolism. A pig model has been used to determine that reproductive function is negatively affected if the normal practice of overfeeding is limited during the late luteal phase of the estrous cycle. We used a sub-set of pigs from this study to examine effects of limiting overfeeding on thyroid hormones and skeletal muscle (i.e. maximal enzyme activities, and muscle fibre characteristics). Eighteen rapidly growing gilts were randomized into three groups: 1) feeding a high plane of nutrition throughout the first 15 days of the estrous cycle; 2) limited overfeeding (25% below the first group) for first 7 days of the estrous cycle (early luteal phase), followed by a high plane of nutrition for days 8-15 (late luteal phase); and 3) high plane of nutrition throughout the first 7 days of the estrous cycle, followed by 8 days of limited overfeeding. Muscle biopsies were collected from the triceps brachii, and blood samples were collected for assessment of thyroid hormones at days 0 (baseline), 8 and 16. There was no effect of limited overfeeding on thyroid hormones, maximal enzyme activities, muscle fibre area or muscle fibre type. Limited overfeeding in rapidly growing pigs does not affect thyroid hormone status or muscle characteristics.

Sequence variation in the bovine and ovine PRNP genes.

A resequencing approach was adopted to identify sequence variants in the PRNP gene that may affect susceptibility or resistance to bovine spongiform encephalopathy. The entire PRNP gene (>21 kb) was sequenced from 26 chromosomes from a group of Holstein-Friesian cows, as well as exon 3 of PRNP (>4 kb) from a further 24 chromosomes from six diverse breeds. We identified 51 variant sequences of which 42 were single nucleotide polymorphisms and nine were insertion/deletion (indel) events. The study was extended to exon 3 of the sheep PRNP gene where 23 sequence variants were observed, four of which were indels. The level of nucleotide diversity in the complete bovine PRNP gene was pi = 0.00079, which is similar to that found at the bovine T-cell receptor alpha delta joining region (pi = 0.00077), but somewhat less than that observed for the bovine leptin (pi = 0.00265). Sequence variation within exon 3 of PRNP in both cattle (pi = 0.00102) and sheep (pi = 0.00171) was greater than that for the complete PRNP gene, with sheep showing greater sequence variation in exon 3 than cattle. The level of sequence variation reported here is greater than previously thought for the bovine PRNP gene in cattle. This study highlights the contribution that recombination plays in increasing allelic diversity in this species.

Response of a sexually transmitted infection epidemic to a treatment and prevention programme in Nairobi, Kenya.

Although it seems possible in a developing country context such as Kenya, given appropriate inputs and a sound approach, to shift a sexually transmitted disease (STI) epidemic from phase II to III, it is not entirely clear how to go beyond this stage, to low levels of endemicity or even elimination. Perhaps the most important challenge now is to expand STI treatment and community STI/HIV prevention programmes to a much larger scale. Although successful programmes have been implemented in many areas of sub-Saharan Africa on a small scale, a significant impact in reducing the STI/HIV burden will not occur until programme reach is expanded to district, provincial, and national levels.

Pharmaceutical management in ProCare Health Limited.

AIMS: To review pharmaceutical budget holding and management in ProCare Health Limited by; describing budget holding strategies implemented in 1995/6, identifying prescribing savings achieved, analysing variation in prescribing behaviour and comparing the findings with experience elsewhere. METHODS: With 340 members, ProCare is one of the largest and most progressive of New Zealand's independent practitioner associations (IPAs). Data were obtained for the three years 1994 to 1996 to determine pharmaceutical expenditure against budget and against national trends, by member and general medical services (GMS) consultations. RESULTS: ProCare has established a classical, quality focussed pharmaceutical management strategy. Savings against the agreed budget was 9.5% comparing 1996 with 1995 but 5.7% compared, with national trends. Wide variation in per capita and per consultation costs was not reduced and was entirely explained by prescribing volumes not drug prices. CONCLUSIONS: The most important finding is that general practitioners (GPs), working collaboratively, can establish a strategy of clinical and corporate governance which may be exerting a wide ranging influence over clinical behaviour. Although there may be doubts about the actual levels of saving these appeared to be well in excess of the financial investment in the strategy. Greater savings appear possible with a focus on addressing the large and apparently inappropriate per capita prescribing volume variation between practices. Understanding and successfully addressing this variation will be one of the key issues facing the implementation of the government's primary health care strategy.

Identification of a novel DRB1 allele, DRB1*1112, by sequence-based DRB typing.

We report here a novel DRB1 allele (DRB1*1112) identified during sequence-based HLA-DRB typing. Polymerase chain reaction with generic DRB primers and group-specific primers and subsequent sequencing yielded identical results. Molecular cloning and sequencing confirmed that the new DRB1 allele is identical to DRB1*11011 and 1129 at exon 2 except for a single nucleotide substitution at codon 37, changing the codon from Tyr (DRB1*11011) or Ser (DRB1*1129) to Phe.

Testing for the presence of previously identified QTL for milk production traits in new populations.

Five chromosomal regions previously associated with milk production traits were tested in 16 families of Black and White cattle from the UK. The traits were also linearly transformed into genetically and phenotypically independent variables normalized by phenotypic variances ('canonical traits'). Significant associations with the untransformed and canonical traits were found for bovine chromosome 6. There was also evidence that chromosome 9 influenced these traits. The linear transformation clarified the effects of chromosomal regions; regions with effects on all three untransformed traits (milk, fat and protein yields) were generally condensed into an effect on a single canonical trait. Comparison of our results with those reported previously for American Holstein cattle suggested that the QTL may not be the same.

Evidence, logic, the rule and the exception in Renaissance law and medicine.

This article sets out to investigate aspects of the uptake of Renaissance law and medicine from some of the logical and natural-philosophical components of the university arts course. Medicine is shown to have a much laxer operative logic than law, reflecting its commitment to the theory of idiosyncrasy as opposed to the demands made upon the law by the need for a uniform application of justice. Symptomatic of the different uptake are the contrasting meanings of "regulariter" and "generaliter" in the two disciplines. Whereas the law treats the rule as inviolable and the exception as only valid if made explicit in due legal form, medicine is able to conceive of a nature as a field of knowledge broader than that encompassed by its rules of art. Both law and medicine approach evidence in ways which reflect their attempts to keep apart the process of information-gathering from that of interpretation; this is exemplified by the legal computation of competing testimony on the one hand and by the various medical modes of sign interpretation on the other.

Functional electrical stimulation exercise increases GLUT-1 and GLUT-4 in paralyzed skeletal muscle.

The study purpose was to determine the effect of functional electrical stimulation (FES)-leg cycle ergometer training (30 minutes on 3 d/wk for 8 weeks) on the GLUT-1 and GLUT-4 content of paralyzed skeletal muscle. Biopsy samples of vastus lateralis muscle were obtained pre- and post-training from five individuals with motor-complete spinal cord injury ([SCI] four men and one woman aged 31 to 50 years, 3 to 25 years postinjury involving C5-T8). Western blot analysis indicated that GLUT-1 increased by 52% and GLUT-4 increased by 72% with training (P < .05). This coincided with an increase in the muscle oxidative capacity as indicated by a 56% increase in citrate synthase (CS) activity (P < .05) and an improvement in the insulin sensitivity index as determined from oral glucose tolerance tests (P < .05). It is concluded that FES endurance training is effective to increase glucose transporter protein levels in paralyzed skeletal muscle of individuals with SCI.

A randomized, double-blind, placebo-controlled trial of single-dose ciprofloxacin versus erythromycin for the treatment of chancroid in Nairobi, Kenya.

A randomized, double-blind, placebo-controlled clinical trial was conducted in Nairobi, Kenya, to compare single-dose ciprofloxacin with a 7-day course of erythromycin for the treatment of chancroid. In all, 208 men and 37 women presenting with genital ulcers clinically compatible with chancroid were enrolled. Ulcer etiology was determined using culture techniques for chancroid, serology for syphilis, and a multiplex polymerase chain reaction for chancroid, syphilis, and herpes simplex virus (HSV). Ulcer etiology was 31% unmixed chancroid, 23% unmixed syphilis, 16% unmixed HSV, 15% mixed etiology, and 15% unknown. For 111 participants with chancroid, cure rates were 92% with ciprofloxacin and 91% with erythromycin. For all study participants, the treatment failure rate was 15%, mostly related to ulcer etiologies of HSV infection or syphilis, and treatment failure was 3 times more frequent in human immunodeficiency virus-infected subjects than in others, mostly owing to HSV infection. Ciprofloxacin is an effective single-dose treatment for chancroid, but current recommendations for empiric therapy of genital ulcers may result in high treatment failure due to HSV infection.

Genetic diversity and mosaicism at the por locus of Neisseria gonorrhoeae.

The por genes of the predominant serovars of Neisseria gonorrhoeae circulating in a high-frequency transmitter core group located in Nairobi, Kenya, were examined for nucleotide sequence polymorphism. The level of por gene diversity did not differ significantly between core group-derived gonococcal strains and gonococcal strains originating elsewhere. However, por mosaicism appeared to be more frequent among core group-derived strains, suggesting that recombination of different por sequences may be a important strategy by which N. gonorrhoeae generates por gene diversity within core group populations. Despite extensive sequence variability, por expressed by gonococcal isolates of different geographic origin exhibited conserved patterns of nucleotide change, suggesting that diversity among por alleles may also be finite.

Identification of a novel HLA-DQA1 allele (DQA1*0106) by sequence-based DQA1 typing.

We report here a novel DQA1 allele (DQA1*0106) identified during sequence-based HLA-DQA1 typing. Polymerase chain reaction with proofreading pfu DNA polymerase and subsequent sequencing yielded identical results as that with Taq DNA polymerase. Molecular cloning and sequencing confirmed that the new DQA1 allele is identical to DQA1*01021/2 at exon 2 except for a single nucleotide substitution (ACT-->GCT), changing codon 44 from Thr to Ala. This is the first report of polymorphism at codon 44 of HLA-DQA1 alleles.

Identification of a novel DQB1 allele DBQ1*0616.

We report here a novel DQB1 allele (DQB1*0616) identified during sequence-based HLA typing. Polymerase chain reaction with proofreading Pwo DNA polymerase and pfu DNA polymerase and subsequent sequencing yielded identical results as that with Taq DNA polymerase. Molecular cloning and sequencing confirmed that the new DQB1 allele is identical to DQB1*0602 at exon 2 except for a single nucleotide substitution (TAC-->AAC), changing codon 60 from Tyr to Asn. This is the first report of polymorphism of DQB1 alleles at codon 60.

Increased interleukin-10 in the the endocervical secretions of women with non-ulcerative sexually transmitted diseases: a mechanism for enhanced HIV-1 transmission?

OBJECTIVE: Although non-ulcerative sexually transmitted diseases (STD) and bacterial vaginosis are implicated as cofactors in heterosexual HIV-1 transmission, the mechanisms have not been defined. Recent in vitro data suggest that interleukin (IL)-10 may increase susceptibility of macrophages to HIV-1 infection. Therefore, we performed this study to assess whether non-ulcerative STD are associated with detection of IL-10 in the female genital tract. METHODS: Women with clinical pelvic inflammatory disease with or without cervicovaginal discharge were recruited from an STD clinic in Nairobi, Kenya. Endocervical and endometrial specimens were obtained for Neisseria gonorrhoeae and Chlamydia trachomatis DNA detection, Trichonomas vaginalis culture, and CD4 and CD8 T-cell enumeration. Bacterial vaginosis was diagnosed by Gram stain. IL-10 was detected in endocervical specimens using enzyme-linked immunosorbent assay. Blood was obtained for HIV-1 serology. RESULTS: One hundred and seventy-two women were studied. N. gonorrhoeae, C. trachomatis, bacterial vaginosis, and T. vaginalis were detected in 38 (21%), 17 (9%), 71 (43%), and 22 (12%) women, respectively. Cervical IL-10 was detected more often in women with N. gonorrhoeae [adjusted odds ratio (AOR), 3.4; 95% confidence interval (CI), 1.4-8.4], C. trachomatis (AOR, 4.4; 95% CI, 1.2-15.6), and bacterial vaginosis (AOR, 3.1; 95% CI, 1.4-6.9) than in women without these infections. CONCLUSIONS: The association of non-ulcerative STD and bacterial vaginosis with increased frequency of IL-10 detection in endocervical secretions suggests a potential mechanism through which these infections may alter susceptibility to HIV-1 infection in women.

Genotyping of Neisseria gonorrhoeae by Pulse Field Gel Electrophoresis and PCR.

Auxotyping (growth of cells on chemically defined media) and serotyping (reaction of cells with a defined set of monoclonal antibodies [MAbs]) are the traditional and most widely used methods for the classification of Neisseria gonorrhoeae isolates. As an example, Knapp et al. (1) used the combination of these two typing techniques to study the epidemiology of 489 isolates of N. gonorrhoeae collected over a 3-mo time period. Separately, 11 different auxotypes and 19 different serotypes were found, but when combined, a total of 57 auxotype/serotype classes were identified. Although this system was and still is very useful for epidemiological studies, some laboratories felt more comfortable using molecular techniques to classify their gonococcal isolates.

Bovine microsatellite loci are highly conserved in red deer (Cervus elaphus), sika deer (Cervus nippon) and Soay sheep (Ovis aries).

We tested 174 bovine microsatellite primer pairs for use in a primitive breed of sheep and two species of deer. Of 173 markers, 127 (73.4%) gave a product in Soay sheep (Ovis aries) of which 54 (42.5%) were polymorphic. One hundred and twenty-nine of 174 (74.1%) markers gave a product in red deer (Cervus elaphus) of which 72 (55.8%) were polymorphic. In sika deer (Cervus nippon) 126 of 171 (73.7%) microsatellite primers gave a product with 47 (37.3%) polymorphic. The proportion of bovine microsatellite loci conserved across artiodactyl species was significantly greater in this study than previously reported. Reasons for this high degree of microsatellite conservation are discussed. We suggest that a high resolution comparative map of the artiodactyls can be constructed using microsatellites.