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931.
Protective effect of early and late administration of pralidoxime against organophosphate muscle necrosis 总被引:3,自引:0,他引:3
Santos RP Cavaliere MJ Puga FR Narciso ES Pelegrino JR Calore EE 《Ecotoxicology and environmental safety》2002,53(1):48-51
The objective of the present investigation was to study the protection afforded by a single administration of pralidoxime against the muscle necrosis induced by the organophosphate compound metamidophos at different times after intoxication. The fiber necrosis of the diaphragm muscle was quantified by a morphometric technique, comparing the area fraction occupied by necrotic muscle fibers in animals that received pralidoxime at different times after intoxication, i.e., 0, 1, 3, 6, and 12 h. Pralidoxime administration protected metamidophos-induced muscle necrosis in all groups studied except for the 12-h group. The earlier the administration of pralidoxime the greater the protection against muscle necrosis. This protection was not accompanied by complete reactivation of plasma cholinesterase activity. Results support the current opinion that pralidoxime should be administered as soon as possible after organophosphate intoxication, because in addition to reversing the muscarinic effects, early administration of pralidoxime also prevents muscle necrosis--which could impair muscular function and respiratory condition. The time difference between recovery of plasma cholinesterase activity and muscle necrosis protection indicates that this method is not completely trustworthy for patient follow-up, since some improvement may occur in spite of the low plasma cholinesterase activity. 相似文献
932.
Magnetization transfer can predict clinical evolution in patients with multiple sclerosis 总被引:3,自引:0,他引:3
Santos AC Narayanan S de Stefano N Tartaglia MC Francis SJ Arnaoutelis R Caramanos Z Antel JP Pike GB Arnold DL 《Journal of neurology》2002,249(6):662-668
The clinical course of multiple sclerosis (MS) is highly variable ranging from benign to aggressive, and is difficult to
predict. Since magnetization transfer (MT) imaging can detect focal abnormalities in normal-appearing white matter (NAWM)
before the appearance of lesions on conventional MRI, we hypothesized that changes in MT might be able to predict the clinical
evolution of MS. We assessed MR data from MS patients who were subsequently followed clinically for 5 years. We computed the
mean MT ratio (MTr) in gray matter, in lesions identified on T2-weighted MRI, and in NAWM, as well as in a thick central brain
slice for each patient. Patients were divided into stable and worsening groups according to their change in Expanded Disability
Status Scale (EDSS) scores over 5 years. We calculated the sensitivity, specificity, predictive value, and odds ratio of the
baseline MTr measures in order to assess their prognostic utility. We found significant differences in baseline MTr values
in NAWM (p = 0.005) and brain slice (p = 0.03) between clinically stable and worsening MS patients. When these MTr values
were compared with changes in EDSS over 5 years, a strong correlation was found between the EDSS changes and MTr values in
both NAWM (SRCC = −0.76, p < 0.001) and in the brain slice (SRCC = 0.59, p = 0.01). Baseline NAWM MTr correctly predicted clinical evolution in 15/18 patients (1 false positive and 2 false negatives),
yielding a positive predictive value of 77.78 %, a negative predictive value of 88.89 %, and an odds ratio of 28. The relationship
between 5-year changes in EDSS and MTr values in T2 weighted MRI lesions was weaker (SRCC = −0.43, p = 0.07). Our data support the notion that the quantification of MTr in the NAWM can predict the clinical evolution of MS.
Lower MTr values predict poorer long-term clinical outcome. Abnormalities of MTr values in the NAWM are more relevant to the
development of future patient disability than those in the T2-weighted MRI lesions.
Received: 3 May 2001, Received in revised form: 11 October 2001, Accepted: 22 October 2001 相似文献
933.
Saponins,IL12 and BCG adjuvant in the FML-vaccine formulation against murine visceral leishmaniasis 总被引:6,自引:0,他引:6
Santos WR de Lima VM de Souza EP Bernardo RR Palatnik M Palatnik de Sousa CB 《Vaccine》2002,21(1-2):30-43
The FML antigen of Leishmania donovani, in combination with either Riedel de Ha?n (R), QuilA, QS21 saponins, IL12 or BCG, was used in vaccination of an outbred murine model against visceral leishmaniasis (VL). Significant and specific increases in anti-FML IgG and IgM responses were detected for all adjuvants, and in anti-FML IgG1, IgG2a and IgG2b and delayed type of hypersensitivity to L. donovani lysate (DTH), only for all saponins and IL12. The QS21-FML and QuilA-FML groups achieved the highest IgG2a response. QuilA-FML developed the strongest DTH and QS21-FML animals showed the highest serum IFN-gamma concentrations. The reduction of parasitic load in the liver in response to each FML-vaccine formulation was: 52% (P<0.025) for BCG-FML, 73% (P<0.005) for R-FML, 93% (P<0.005) for QuilA-FML and 79.2% (P<0.025) for QS21-FML treated animals, respectively. Protection was specific for R-FML and QS21-FML while the QuilA saponin treatment itself induced 69% of LDU reduction. The FML-saponin vaccines promote significant, specific and strong protective effects against murine visceral leishmaniasis. BCG-FML induced minor and non-specific protection while IL12-FML, although enhancing the specific antibody and IDR response, failed to reduce the parasitic load of infected animals. 相似文献
934.
Borja-Cabrera GP Correia Pontes NN da Silva VO Paraguai de Souza E Santos WR Gomes EM Luz KG Palatnik M Palatnik de Sousa CB 《Vaccine》2002,20(27-28):3277-3284
Naturally exposed dogs of an endemic area were vaccinated with the fucose mannose ligand (FML) antigen of Leishmania donovani in formulation with QuilA saponin. The 100% of vaccinees were seropositive to FML and showed intradermal reaction to L. donovani lysate, 2 months after vaccination. The absorbency values and size of intradermal reaction were both significantly higher in vaccinees than in controls along a 3.5 years period (ANOVA, P<0.0001). The 25% of the control animals (two dogs on the first year and six dogs on the fourth year, respectively) and 5% of the vaccinees (one dog during the fourth year) developed clinical and fatal disease until the end of experiment. This difference was significant (chi(2)=3.93, P<0.05). This means that 95% protection against kala-azar was achieved in vaccinees, after FML-QuilA vaccination (80% of vaccine efficacy (VE)). Leishmania infection was also confirmed, 3.5 years after vaccination, in saline controls that showed positive polymerase chain reaction (PCR) for Leishmania DNA and FML-serology with no intradermal reaction. Higher seropositivities and intradermal reactions with no Leishmanial DNA were detected in vaccinees. The FML-QuilA vaccine induced a significant, long lasting and strong protective effect against canine kala-azar in the field. 相似文献
935.
Ferrara A Morosini M Dos Santos C Fietta A 《Journal of chemotherapy (Florence, Italy)》2002,14(6):568-573
Drug susceptibility test results of respiratory tract pathogens, isolated from patients admitted to the Clinic of Respiratory Diseases of the IRCCS San Matteo Hospital, University of Pavia (Italy) between 1990 and 1999, were retrospectively evaluated. A total of 1366 bacterial isolates were collected, including 499 gram-positive and 867 gram-negative strains. In comparison to methicillin-susceptible Staphylococcus aureus, the methicillin-resistant strains (MRSA) showed high levels of resistance to many selected antibiotics, except for glycopeptides. Resistance rates to beta-lactams were high in both Pseudomonas aeruginosa and in the other gram-negative isolates, while aminoglycoside and ciprofloxacin resistance was less than 20%. Some pathogens became more resistant to selected antimicrobials during the observation period, including staphylococci to methicillin, MRSA to ciprofloxacin, P. aeruginosa isolates to imipenem and ciprofloxacin, and the other gram-negative strains to almost all drugs considered, with the exception of cefotaxime and cotrimoxazole. 相似文献
936.
A case of endolymphatic sac adenocarcinoma is reported and the literature is reviewed. The clinical picture was presented by vertigo and progressive hearing loss caused by a tumor of the endolymphatic sac. The surgical removal was complete, via a retro and translabyrinthine approach. Endolymphatic sac tumors are locally invasive, involve the petrous bone and the mastoid. The radical surgery presents good outcome. 相似文献
937.
Monge-Argiles J Maloteaux J Van Den Bergh P Sindic C 《Neurología (Barcelona, Spain)》2002,17(2):110-112
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis. 相似文献
938.
Background: This study evaluated the effect of moxifloxacin and comparator drugs with or without some fractions of pulmonary surfactant,
as surfactant protein-A (SP-A) and phospholipids, on the adherence of the most common respiratory pathogens.
Materials and Methods: The adherence of respiratory pathogens to a bronchial epithelial cell line was tested. Antimicrobials were used at 1/2, 1/4
and 1/8 minimum inhibitory concentration (MIC), SP-A at 1 and 5 μg/ml and phospholipids at 50 μg/ml.
Results: At 1/2 MIC moxifloxacin, ciprofloxacin, amoxicillin-clavunalate and ceftriaxone reduced the adherence of Staphylococcus aureus and Streptococcus pneumoniae to values of 40-50%. At the same concentration, cotrimoxazole reduced the adherence values of Moraxella catarrhalis and Haemophilus influenzae to about 50%, while β-lactams showed high efficacy only on H. influenzae, with adherence values of about 40%. The addition of SP-A and/or phospholipids to the tested antibiotics had no effect on
bacterial adherence.
Conclusion: The non-interference of SP-A and/or phospholipids with the suppressive effect that some antibiotics exert on bacterial adherence
could represent a favorable event during antibiotic therapy.
Received: March 23, 2001·Revision accepted: May 10, 2002 相似文献
939.
940.
Cr(V)involvementin the toxicity pathway of testicular damage 总被引:1,自引:0,他引:1
Pereira ML Santos TM das Neves RP Costa FG de Jesus JP 《Asian journal of andrology》2002,4(2):153-155
AIM: The functional integrity of the blood-testis barrier (BTB) in male mice exposed to Cr(V) was studied in order to clarify the mechanism underlying testicular injury. METHODS: Adult male mice were subcutaneously injected repeated doses of 8.02 micromol (0.5 ml) of Cr/mouse.day for 5 days. Animals receiving a similar volume of bis(hydroxyethyl)-aminotris(hydroxymethyl)methane buffer (BT) were used as controls. The animals were sacrificed on day 6 and small fragments of seminiferous tubules, approximately 8-10 mm length, were incised and sutured at both ends. They were exposed in vitro to horseradish peroxidase-containing culture medium for 10 minutes. Tissues were then fixed and processed for ultrastructural studies. RESULTS: Controls and Cr(V)-treated group resulted in the uptake of the tracer by Sertoli cells. However, the major finding consisted in the permeability of the BTB only in the Cr(V)-group, as evidenced by the presence of the tracer within the junctions between the neighbouring Sertoli cells. CONCLUSION: The BTB is disrupted in mice submitted to Cr(V). The permeability of the BTB is a crucial feature to be investigated for the understanding of lesions within the seminiferous tubule. 相似文献