Effect of Long-Term in Vitro Sub-culturing on Quality Degeneration of Sweet Potato Varieties： Morpho- Anatomic Assessment and Simple Sequence Repeats Analysis

The aim of this study was to assess the effect of long-term in vitro sub-culturing on the varietal degeneration of three sweet potato varieties, namely, Monate, Mokone and Ndou which were sub-cultured for 32, 23 and 12 generations, respectively. Each generation was cultured in a media which is made from 4.43 g/L Murashige and Skoog （MS）, 30 g/L sucrose and 2 g/L gelrite, respectively, and grown under 16 h light and 8 h dark photoperiod for 30 d. For each generation, 45 plantlets were acclimatized for two months in a glasshouse. Data on in vitro growth performance and 11 morphological characteristics during acclimatization were recorded. Early root and shoot formation was observed after the 27th and 21st sub-cultured generations of Monate and Mokone, respectively. During acclimatization, plantlets from the same variety showed differences in morphological traits such as leaf colour, abaxial leaf pigmentation, vine pigmentation, petiole pigmentation, leaf wrinkling and flowering. However, the rate of these morphological differences is random and irrespective to increase in sub-culturing. Therefore, to understand the genetic base of these morphological variability, two plantlets from each variety were subjected to genetic analysis by using five simple sequence repeat （SSR） primers （IB-242, IB-318, IB-255F, 1B-248 and IB-255）. Although SSR loci IB-255F and IB-318 could distinguish between the three varieties, there were no allelic polymorphisms detected in plantlets from the same varieties. Therefore, long-term sub-culturing do not leads to quality degeneration in the three sweet potato varieties.     

Nuclear scanning with 99mTc-HDP for the initial evaluation of osseous metastasis in canine osteosarcoma

The purpose of this retrospective analysis was to evaluate the use of nuclear scintigraphy in determining the rate of secondary sites of osseous malignancy at initial presentation in dogs with osteosarcoma. Radiographs of suspicious secondary lesions were reviewed and placed into four separate categories: benign lesions; no lesion seen on radiographs; subtle radiographic changes suggestive of, but not conclusive for, metastasis; and metastatic lesions highly suspected on radiographs. Three hundred and ninety‐nine dogs were evaluated by technetium nuclear scanning for suspected osteosarcoma. Three hundred and twenty‐six of 399 dogs (82%) had only one apparent site on the nuclear scan, whereas 72 dogs (18%) had more than one suspicious site on the nuclear scans. Highly suspected secondary metastatic lesions were detected by nuclear scans in 7.8% of cases. Although interpretation of nuclear scans is subjective, this study showed a 7.8% chance of detecting unsuspected osseous metastasis with nuclear scans in canine osteosarcoma patients on initial presentation.     

Prevalence and determinants of stunting and overweight in 3-year-old black South African children residing in the Central Region of Limpopo Province, South Africa

OBJECTIVES: To determine the prevalence of stunting, wasting and overweight and their determinants in 3-year-old children in the Central Region of Limpopo Province, South Africa. DESIGN: Prospective cohort study. SETTING: Rural villages in the Central Region of the Limpopo Province, South Africa. SUBJECTS: One hundred and sixty-two children who were followed from birth were included in the study. Anthropometric measurements and sociodemographic characteristics of the children were recorded. RESULTS: Height-for-age Z-scores were low, with a high prevalence of stunting (48%). The children also exhibited a high prevalence of overweight (22%) and obesity (24%). Thirty-one (19%) children were both stunted and overweight. Gaining more weight within the first year of life increased the risk of being overweight at 3 years by 2.39 times (95% confidence interval (CI) 1.96-4.18) while having a greater length at 1 year was protective against stunting (odds ratio (OR) 0.41; 95% CI 0.17-0.97). Having a mother as a student increased the risk for stunting at 3 years by 18.21 times (95% CI 9.46-34.74) while having a working mother increased the risk for overweight by 17.87 times (95% CI 8.24-38.78). All these factors also appeared as risks or as being protective in children who were both overweight and stunted, as did living in a household having nine or more persons (OR 5.72; 95% CI 2.7-12.10). CONCLUSION: The results of this study highlight the importance of evaluating anthropometric status in terms of both stunting and overweight. Furthermore, it is important to realise the importance of normal length and weight being attained at 1 year of age, since these in turn predict nutritional status at 3 years of age.     

COMPARISON OF RADIOGRAPHIC SUBCHONDRAL BONE CHANGES WITH ARTHROSCOPIC FINDINGS IN THE EQUINE FEMOROPATELLAR AND FEMOROTIBIAL JOINTS: A RETROSPECTIVE STUDY OF 72 JOINTS (50 HORSES)

Radiographs of 72 femoropatellar and femorotibial joints from 50 horses were evaluated. Ninety four arthroscopically evaluated areas were graded according to a predetermined system. The radiographic grade was then compared to arthroscopic findings in the same location. Statistical analysis was performed to determine the association between the radiographic subchondral bone changes and arthroscopic findings. Radiographically normal areas in the femoropatellar joint were arthroscopically positive for cartilaginous changes in 40% of the femoropatellar joints. Areas of mild subchondral bone flattening (grade I) in the lateral trochlear ridge were arthroscopically positive for cartilage changes 78% of the time. Ninety six percent of moderate to severe subchondral bone changes (grades II-V) were arthroscopically positive for cartilage damage. This research demonstrates that (1) a significant number of radiographically normal joints will have cartilage changes, (2) areas of mild subchondral bone flattening have cartilage changes present in the majority of cases and (3) areas of moderate to severe subchondral bone changes have arthroscopically detectable cartilage changes present.     

Stability and partitioning of closantel and rafoxanide in ruminal fluid of sheep

The stability and the partitioning of closantel and rafoxanide in ruminal fluid (RF) was examined in vitro. Stability was evaluated in two studies in a ruminal fluid-artificial saliva (RF-AS) mixture containing either drug. Drug concentrations were measured in samples collected sequentially from four batches of RF-AS fortified with either closantel or rafoxanide in one study and in four separately incubated aliquots of a RF-AS mixture of each drug in the second study at the start and at various intervals during a 24 h incubation period. The viability of the in vitro RF-AS incubation model was validated by the presence of digoxin degradation (T1/2 of 39,1 +/- 13 h) and by the absence of significant time related differences (P> 0,5) in volume of gas produced, pH and methylene blue reduction time of the RF-AS drug mixture. Partitioning of closantel and rafoxanide was determined by measuring the relative drug concentration of the fluid and particulate phases in RF fortified with either drug at different concentrations. Closantel and rafoxanide were shown to be stable in a RF-AS mixture and were not subjected to any significant biodegradation. An initial marked reduction in drug concentration measured in the RF-AS mixture during the first 2 h of incubation was attributed to the attachment of both drugs onto particulate matter. This was subsequently confirmed in the partitioning study. More than 80% of closantel and rafoxanide was shown to be associated with the particulate phase of RF     

Intravascular plasma disposition and salivary secretion of closantel and rafoxanide in sheep

The plasma and salivary disposition of closantel and rafoxanide were examined following intravenous administration in adult sheep. Two studies were conducted with rafoxanide at 7.5 mg/kg and 1 with closantel using 2 doses (5 and 15 mg/kg). The pharmacokinetic profile of both drugs in plasma were best described by a 2-compartmental model with 1st-order rate constants. Plasma disposition of closantel and rafoxanide were characterised by a rapid distribution (t1/2(alpha)) of <30 min), long elimination half-life (t1/2(beta)) of 17.0 +/- 4.0 days for closantel and 7.2 +/- 0.6 days for rafoxanide), small apparent volume of distribution (V(SS) of <0.15 l/kg) and a slow rate of total body clearance (Cl of <0.01 ml/min/kg). The area under the drug plasma concentration curve (AUC) of closantel at 5 mg/kg was nearly twice as large as that of rafoxanide at 7.5 mg/kg resulting from the slower t1/2(beta) observed with closantel compared to rafoxanide. Large individual differences were observed in the rate measurements of distribution (k12, k21 and t1/2(alpha)), whereas the parameters of elimination (k10, t1/2(beta) and Cl), were more consistent between animals. A dose proportional increase in AUC was observed for closantel administered at 5 and 15 mg/kg. A low, constant salivary concentration of closantel (mean of 0.04 +/- 0.05 microg/mL) and rafoxanide (mean of 0.07 +/- 0.04 microg/mL) was observed during the 24-h examination period after dosing.