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Intestinal nematodes remain a world health issue. Their ubiquitous nature makes them difficult to control, and treatment is ineffective when the source of the infection can not be eradicated. International travel and immigration from developing countries have effectively increased the numbers of people infected in the US, especially in the northeast and southern coastal areas. It is important to provide sensitive and accurate methods to diagnose these parasites. Additionally, the WHO and other agencies must remain vigilant and continue their efforts to improve the health of vulnerable populations throughout the world.  相似文献   
63.
PT-9K/129G, a nontoxic mutant of pertussis toxin (PT) obtained by genetic manipulation, has been shown in animal models to be a promising candidate for new vaccines against whooping cough. To assess the safety and the immunogenicity of PT-9K/129G in humans, a pilot study has been performed in adult volunteers. The protein was found to be safe, capable of inducing high titers of toxin-neutralizing antibodies, and capable of generating immunological memory. In fact, vaccination caused an increase of cell-mediated response to PT, PT-9K/129G, S1 subunit, and B oligomer, indicating that memory T cells are induced by the vaccine. Since PT-9K/129G is mitogenic for T lymphocytes in vitro, it was investigated whether this activity is also present in vivo. No variation was observed in the proportion of T cells (CD3+), T helper cells (CD4+), and cytotoxic T cells (CD8+), as well as in that of other lymphoid populations, by FACS analysis. Interestingly, no thorough correlation was found between humoral and cellular responses. In one case, a very high cellular response was present in absence of detectable antibodies, suggesting that the antibody response, which is the only parameter measured in most clinical trials, may not give a complete picture of the response induced by a vaccine.  相似文献   
64.
BACKGROUND: The reported sensitivities and specificities of procalcitonin (PCT) concentrations for the diagnosis of neonatal infection vary widely. A postnatal increase of PCT has been observed in healthy term newborns with a peak at approximately 24 h of age, and many questions remain regarding maternal and perinatal factors that may influence the normal PCT kinetics during the immediate postnatal period. METHODS: We prospectively investigated the association between the serum PCT values obtained from 121 mothers at delivery and serum PCT in their healthy, term offspring at birth as well as at 24 and 48 h of age. We also analyzed whether obstetric and perinatal factors would alter maternal and neonatal PCT response. RESULTS: PCT concentrations in the babies at birth were significantly higher than in the mothers (P <0.0001), with even larger differences at 24 and 48 h of age. None of the variables identified from maternal and perinatal histories had a significant effect on maternal PCT response. In the healthy neonate, the variables that significantly affected the concentration of PCT at birth were the mothers' PCT (P <0.01), maternal group B streptococcus colonization (P <0.05), and rupture of membranes >/=18 h (P <0.01). The coefficient of linear correlation between the mother's PCT concentration and that of the baby at birth was 0. 32 (P <0.01). The only variable that significantly altered the PCT concentration at both 24 (P <0.01) and 48 (P <0.01) h of age was rupture of membranes >/=18 h. Nonetheless, the PCT response observed during the 48-h period after birth among healthy babies born to mothers with risk factors for infection was well below that reported previously among age-matched neonates with sepsis. CONCLUSIONS: The postnatal increase of PCT observed in the healthy neonate with peak values at 24 h of age most likely represents endogenous synthesis. In estimating the sensitivities and specificities of PCT for diagnosis of sepsis throughout the initial 48 h of life, it is important to consider the normal PCT kinetics and the pattern(s) of PCT response in the healthy neonate.  相似文献   
65.

Background

The field of laparoscopy has undergone several changes to improve the morbidity and cosmesis of laparoscopic surgery. The robotic single-site surgery is the inevitable hybridization of robotic technology with laparoendoscopic single-site surgery.

Methods

Perioperative information of 12 robotic single-site hysterectomies (R-SSH) were collected to evaluate the surgical feasibility and the possible influence of the body mass index (BMI) and the uterine weight on operative times.

Results

The mean operative time was 85 ± 33 min (range, 355 to 149 min), the mean docking time was 9 ± 3 min, and the mean console time was 76 ± 33 min. The mean blood loss was 80 ± 18 mL, and the median weight of resected uteri was 220 ± 45 g. No serious postoperative complications occurred. The CUSUM learning curve was observed to consist of two different phases: phase 1 (the initial 6 cases) and phase 2 (the last 6 cases) with significant reduction in operative and console time observed between the two phases. For BMI, no correlation was found with operative times, console times, and docking times, and no correlation was found between uterine weight and operative time.

Conclusions

This series, identifying two different phases of the learning curve and suggesting that the initial learning phase for the procedure can be achieved after six cases, confirms the feasibility and safety of a robotic approach for single-site hysterectomy. However, the limits of this study mainly rely on the limited casuistic and short follow-up, although the preliminary results appear promising. Larger series and prospective studies comparing R-SSH hysterectomy with standard robotic multiport hysterectomy are necessary to define properly the role of this innovative surgical technique.  相似文献   
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Calcium phosphates (CaP) are the main constituents of the mineral phase in bones and teeth and, along with calcium silicates and bioactive glasses, have been extensively investigated in remineralization of enamel and dentin. When used as ion-releasing fillers in resin-based materials, they could contribute to extend the service life of adhesive restorations, remineralize caries-affected dentin or prevent caries lesions under sealants and orthodontic brackets. However, the development of resin-based bioactive materials is not straightforward because of the several compositional variables involved in ion release. Also, CaP particles do not reinforce the material; therefore, if high mechanical properties are required, the ratio between CaP particles and reinforcing fillers must be observed. Several research groups have investigated how CaP phase, particle size and content, as well as resin matrix formulation affect remineralization, ion release kinetics and mechanical properties of these materials. This review presents an overview of the main findings reported in the literature.  相似文献   
68.
An imbalance between pro-angiogenic and anti-angiogenic factors is hypothesized in the pathogenesis of ovarian cystic disease. The aim of the following study was to explore the possible role of free vascular endothelial growth factor receptor 1 (sVEGFR-1), a soluble regulator of vascular endothelial growth factor (VEGF) action, in ovarian cystoadenoma, endometriomata and cystoadenocarcinoma. Forty-eight women, of whom fourteen had ovarian serous cysts, twenty-eight had stage III-IV ovarian endometriomata, and six had stage IIIB-IIIC ovarian carcinoma, were included. Sampling of serum, peritoneal and ovarian cystic fluids and of tumor tissue was performed before, during and following surgery, respectively. Levels of VEGF and sVEGFR-1 were measured in serum, peritoneal and cystic fluid. VEGF and sVEGFR-1 expression was evaluated in tumor tissue. There were no differences in serum VEGF and sVEGFR-1 levels nor in VEGF/VEGFR-1 ratio between study groups. Peritoneal fluid VEGF levels were higher in cystoadenocarcinoma patients than in endometriosis and in cystoadenoma patients, while sVEGFR-1 peritoneal fluid concentrations were significantly higher only in endometriosis-affected women. VEGF/VEGFR-1 ratio was highest in the peritoneal fluid of cancer patients with respect to the other two groups of women. Cystic fluid VEGF and VEGFR-1 concentrations were higher in endometriomata and in cystoadenocarcinomas than in cystadenomas but the VEGF/VEGFR-1 ratio was highest in cancer patients. Western blot evidenced a marked expression of VEGF and soluble VEGFR-1 in endometriosis tissue with respect to benign cyst tissue but a lower expression of both molecules, contrary to that expected, in cancer tissue. In conclusion, all in all, our data indicate that an excess of local VEGF with respect to its soluble receptor VEGFR-1 may be a key factor in the onset and maintenance of pathological neo-angiogenesis in ovarian cyst formation.  相似文献   
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