Effects of sodium bicarbonate supplementation on axial and peripheral bone mass in rats on strenuous treadmill training exercise

We observed the effects of sodium bicarbonate supplement on bone mass in rats on strenuous treadmill training. Sixty female Wistar rats (93-days-old; mean initial weight 261 ± 16 g) were studied. One group of 15 rats was killed at the beginning of the experiments (basal control group), while another group of 15 rats was not manipulated (Exer−NaB−). Another group of 15 rats was exercised but did not receive sodium bicarbonate (Exer+NaB−), while the final group of 15 rats exercised and received sodium bicarbonate (Exer+NaB+) at a dose of 0.05 mg/kg/day, administered by esophageal catheter on exercise days. These rats were killed at the end of 11 weeks. Femoral and vertebral length, weight, and bone mineral content (BMC) and density (BMD) were measured. According to anova with the Tukey–Kramer test, femur length and weight, vertebral weight, femur BMC and BMD, vertebral BMC and BMD and the ratio between femur and vertebral BMC and final body weight, and plasma bicarbonate were lower in the basal control and Exer+NaB− groups than in the two other groups (P < 0.005–0.0001). Overall, there was a positive correlation between femur and vertebral BMC and femur BMC and length (P < 0.0001 for all). Only in the Exer+NaB− group was there a positive association between plasma bicarbonate levels and femur length (r = 0.78; P < 0.0005). Our study demonstrates the adverse effects of strenuous exercise on bone, and the usefulness of sodium bicarbonate supplements in preventing and minimized these effects. Received: May 1, 2000 / Accepted: August 11, 2000     

Prognostic Index for Extremity Soft Tissue Sarcomas With Isolated Local Recurrence

Background: Local recurrence occurs in 10% to 20% of patients with extremity soft tissue sarcomas despite optimal treatment. The association of local recurrence with subsequent survival is controversial and conflicting. There is a need for a staging system to predict outcome in this subset of patients and also to plan optimal treatment, including adjuvant systemic therapy.Methods:Data collected from 110 patients with locally recurrent extremity soft tissue sarcomas were studied. The influence of clinical and pathologic factors on local recurrence, distant metastasis, and disease-specific survival were analyzed by univariate and multivariate techniques.Results: Of the 110 patients who presented with local recurrence, 92 had an isolated local recurrence and 18 had prior or concomitant distant metastases. The 5-year disease-specific survival for all patients was 63% and for those with isolated local recurrence, it was 69%. Histologic grade, malignant fibrous histiocytoma histology, pathologic margins, previous local recurrence, and prior radiotherapy were independent prognostic factors for subsequent local recurrence. Tumor size, histologic grade, and time to local recurrence were independent prognostic factors for distant metastasis and disease-specific survival. A prognostic index was calculated by assigning a score of 1 to 3 for each of the three independent prognostic factors for survival and added to give the prognostic index for each patient. As the prognostic index increased from 3 to 9, there was a progressive increase in the hazard ratios and a corresponding deterioration in survival. The patients were then categorized into three prognostic groups based on the hazard ratios for disease specific survival. The differences in the survival curves were highly statistically significant (P < .0001).Conclusions: Tumor size, histologic grade, and time to local recurrence are the primary determinants of distant metastases and survival in locally recurrent extremity soft tissue sarcomas. The impact of local recurrence on survival varies considerably. The nature of the local recurrence, rather than its presence per se, is a more useful guide to prognosis. We propose a simple staging system based on size, grade, and time to recurrence that correlates extremely well with prognosis and may serve as a guide to make therapeutic decisions in patients with locally recurrent extremity soft tissue sarcomas.     

Experimental study of antiseptic (tauroline, taurolidine) and antibiotic (sulmycin implant) drugs in vascular prosthesis infections in a standardized infection model

It was the aim to examine whether local application of antiseptic and antibiotic substances is an effective treatment of vascular graft infection. MATERIAL AND METHODS: 19 pigs with a bodyweight between 20 and 30 kg were assigned to three different groups. Group I: control (6), group II: local treatment with Sulmycin implant, group (6) III: local treatment with Taurolin (Taurolidine) (7). An unprotected vascular graft was inserted in the right femoral artery of all pigs. After finishing the proximal and distal anastomosis and prior to closure of the incision, the vascular grafts were contaminated locally with 2 x 10(7) CFU/ml Staphylococcus aureus ATCC 29213. Seven days later all animals received another unprotected vascular prosthesis with or without additional treatment according to groups I, II, III. 28 days after primary operation the animals were euthanized and the grafts harvested. The specimens were examined for signs of infection by histology and microbiology. RESULTS: After the primary operation all animals presented with infected vascular prosthesis. At termination of the trial on day 28 all grafts of group I were contaminated, 5 out of 6 grafts in group II, and 5 out of 7 in group III presented with infected grafts. There was no significant statistical difference between the groups. Infection could not be prevented by the antimicrobial agents used. The primary infecting organism Staphylococcus aureus, however, was eliminated in all cases. CONCLUSIONS: Both antimicrobial substances examined were not effective in the treatment of vascular graft infection, but might be used as adjuvant therapy of vascular graft infection, whereby Sulmycin implant seems to be more effective regarding the incorporation of the prosthesis.     

Identification and typing of Yersinia enterocolitica biotypes and serotypes isolated

OBJECTIVE: To assess the presence of Yersinia enterocolitica in otherwise healthy pigs slaughtered for human consumption. METHODS: One hundred pharyngeal tonsils were sampled in a slaughterhouse in the state of Mexico. The minimum sample size (n=100) was calculated based on a preliminary sample of 20 cases, which had 20% positive cases. The collected tonsil samples were inoculated in Rappaport broth, and Salmonella-Shigella and McConkey media. The biotyping identification process was based on biochemical and serological tests using O:3, O:8 and O:9 antisera. RESULTS: Twenty-two isolates were obtained. Most were biotype 1 (8 cases of O:3 and 8 cases of O:9), but 6 cases could not be serotyped. None of the isolates were of O:8 group. CONCLUSIONS: This was the first time that Y. enterocolitica serotypes were isolated from pig tonsils in Mexico. Its importance rely on the fact that the isolated serotypes are the most commonly found in public health problems.     

Synthetic peptide vaccine against Taenia solium pig cysticercosis: successful vaccination in a controlled field trial in rural Mexico

Taenia solium cysticercosis seriously affects human health when localised in the central nervous system (CNS) and causes great economic loss in pig husbandry in rural areas of endemic countries. Increasing the resistance to the parasite in the obligatory host pig may help in curbing transmission. Three synthetic peptides based on protein sequences of the murine parasite Taenia crassiceps, which had previously been shown to induce protection in mice against homologous challenge, were tested as a vaccine against T. solium cysticercosis in pigs. Vaccinated and unvaccinated piglets (240 in all) were distributed in pairs among the peasants' households of two rural villages in Mexico in which 14% of the native pigs were cysticercotic. Ten to twelve months later, the effect of vaccination was evaluated at necropsy. Vaccination decreased the total number of T. solium cysticerci (98.7%) and reduced the prevalence (52.6%). The natural challenge conditions used in this field trial strengthen the likelihood of successful transmission control to both pig and human through a large-scale pig vaccination program. We believe this is a major contribution in anticysticercosis vaccine development as these rather simple yet protective peptides are potentially more cost-effective to produce and less variable in results than antigens that are more complex.     

Onset of tuberculosis disease: new converters in long-term care settings

Elders living in communal settings, such as nursing homes or other types of long-term care facilities have a tuberculosis (TB) incidence rate of 39.2 per 1,000, nearly four times the rate of TB in the general population. This fact mandates routine screening, reporting, and strict follow-up of TB in long-term care facilities as well as recognizing and addressing barriers to worker and resident protection. As healthcare in this country evolves from acute care facilities to alternative ambulatory care settings, the focus for infection control personnel is to develop effective TB control plans appropriate to the care setting using current clinical guidelines set forth by the Centers for Disease Control and Prevention (CDC) or other agencies, the main goal of which is to reduce the number of infections and exposures to this disease. As the incidence of TB continues in long-term care settings, away from acute care facilities, public health officials, administrators, and infection control personnel need to develop TB control plans, risk assessment procedures, and appropriate follow-up on positive converters among the workers and the residents. The case study presented herein is a good example of an individual being offered a screening test for an infectious airborne disease and positive test results being disregarded.