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131.
Martínez de Villarreal L Pérez JZ Vázquez PA Herrera RH Campos Mdel R López RA Ramírez JL Sánchez JM Villarreal JJ Garza MT Limón A López AG Bárcenas M García JR Domínguez AS Nuñez RH Ayala JL Martínez JG González MT Alvarez CG Castro RN 《Teratology》2002,66(5):249-256
BACKGROUND: Nuevo León is a state in northeastern Mexico, near the border of Texas. Mean mortality rate from 1996-98 due to anencephaly cases was 0.6/1,000. In 1999 a surveillance program for the registry and prevention of neural tube defects (NTD) cases was initiated. METHODS: Cases were obtained from hospitals and OB-GYN clinics by immediate notification, death certificates, or fetal death registries. Only isolated cases of NTD were included. In August 1999 a folic acid campaign was initiated with the free distribution of the vitamin to low-income women with a recommendation to take a 5.0-mg pill once a week. Number of cases and rates from 1999 to 2001 were compared (chi(2) test). RESULTS: After 2 years there has been a significant reduction in the number of cases and rates. In 1999 there were 95 NTD cases and in the years 2000 and 2001 there were only 59 and 55 respectively (P < 0.001). NTD rate decreased from 1.04/1,000 in 1999 to 0.58/1,000 in 2001. Anencephaly and spina bifida rates decreased from 0.55/1,000 to 0.29/1,000 and from 0.47/1,000 to 0.22/1,000 respectively, from 1999-2001. Decrease of female cases was higher than male cases for both phenotypes. CONCLUSION: After 2 years there was a 50% decrease in the incidence of anencephaly and spina bifida cases with a significant reduction of infant mortality and disability. These results encourage us to propose the use of a single tablet of 5.0-mg of folic acid per week as an alternative to supplementation on a daily basis. 相似文献
132.
Aguilar-Setién A Leon YC Tesoro EC Kretschmer R Brochier B Pastoret PP 《Journal of wildlife diseases》2002,38(3):539-544
Adult vampire bats (Desmodus rotundus) were vaccinated by intramuscular, scarification, oral, or aerosol routes (n = 8 in each group) using a vaccinia-rabies glycoprotein recombinant virus. Sera were obtained before and 30 days after vaccination. All animals were then challenged intramuscularly with a lethal dose of rabies virus. Neutralizing antirabies antibodies were measured by rapid fluorescent focus inhibition test (RFFIT). Seroconversion was observed with each of the routes employed, but some aerosol and orally vaccinated animals failed to seroconvert. The highest antibody titers were observed in animals vaccinated by intramuscular and scarification routes. All animals vaccinated by intramuscular, scarification, and oral routes survived the viral challenge, but one of eight vampire bats receiving aerosol vaccination succumbed to the challenge. Of 31 surviving vaccinated and challenged animals, nine lacked detectable antirabies antibodies by RFFIT (five orally and four aerosol immunized animals). In contrast, nine of 10 non-vaccinated control bats succumbed to viral challenge. The surviving control bat had antiviral antibodies 90 days after viral challenge. These results suggest that the recombinant vaccine is an adequate and safe immunogen for bats by all routes tested. 相似文献
133.
Until the present moment, only a scarce number of Latin American domestic cat populations have been studied from a population genetic standpoint. For this reason, the cat populations of La Havana (Cuba), San José (Costa Rica), Bogota and Ibagué (Colombia), Asuncion (Paraguay), Santiago (Chile) and Buenos Aires (Argentina) were sampled for several coat genes. The results obtained were as follows: (1) there was a strong genetic resemblance between several Hispanic American cat populations (especially, those of Buenos Aires, San José and the two Colombian populations studied) and those from South Western United States (California, Texas and Colorado), which adds support to the suspicion that these populations probably have a common origin; (2) The cat population of Santiago (Chile), contrarily to the other Hispanic American populations studied, showed a strong genetic resemblance with some Anglo North American populations; and (3) The l (long hair) and d (dilution) alleles showed systematic higher frequencies in the Hispanic American populations than those observed in Spain. Although the Hispanic American populations were not identical to the current Spanish populations (with the exception of Asuncion), this historic genetic experiment was very different to that found for the British populations and their overseas colonies. 相似文献
134.
Hahn RC Macedo AM Santos NL Resende JC Hamdan JS 《Revista iberoamericana de micología》2002,19(1):49-51
Two atypical Paracoccidioides brasiliensis strains (yeast form at room temperature) have been isolated from chronically infected patients living in Brazil. Different random primers were used to characterize these isolates and compare them to typical strains. The RAPD patterns allowed the differentiation of all the selected isolates. Their genetic distance ranged from 5% to 80% of non-shared bands depending on the strains and the primer used. The RAPD data were used to build a Wagner phenogram, which showed two major branched with more than 56% of genetic distance separating them. No significant difference was observed between the atypical isolates and the others suggesting that specific genes are involved in the dimorphism phenomenon. 相似文献
135.
Gómez L Hernández R Ibarra N Valdés R Campos Y Tamayo A Fernández D Figueroa A Alvarez T Montero JA 《Journal of biochemical and biophysical methods》2002,52(3):151-159
Different ligand densities of monoclonal antibody (Mab) CB.Hep-1 were studied during covalent coupling on Sepharose CL-4B for recombinant hepatitis B surface antigen (rHBsAg) immunoaffinity purification. Ligand densities of 2.2, 3.2, 4.2 and 5.2 mg Mab/ml immunosorbents, respectively, were assayed during five cycles of immunoaffinity chromatography (IAC). Adsorption capacities averaged either 3.2 mg/ml (0.57 mg rHBsAg/ml immunosorbent/5.42 mg of total purified protein) or 5.2 mg/ml (0.56 mg rHBsAg/ml immunosorbent/5.05 mg total purified protein). Immunosorbents showed ligand leakage levels below 3 ng Mab/microg rHBsAg. Antigen purity was higher than 95% in all cases. The results suggest that a ligand density (LD) of 3.2 mg Mab/ml immunosorbent should be used for immunoaffinity chromatography because no significant differences were found in the ligand densities studied (P-value=0.012), which saves 40% of CB.Hep-1 immunosorbent manufacturing cost in comparison with 5 mg Mab/ml immunosorbent, which is currently used in large-scale production. 相似文献
136.
Alvarez I Del Carmen Saldías M Wodowoz O Pérez Campos H Machin D Silva W Sueta P Pérez N Acosta Md Mdel C 《Cell and tissue banking》2003,4(2-4):173-178
The transplant law of 1971 based on informed consent, allows people to register their willingness to be a donor upon death. Since 1978 the governmental Institution, the National Bank of Organs and Tissues (BNOT), have been regulated the organ and tissue donation. Important progress was implemented in the BNOT and specially in the National Multi-tissue Bank (NMTB). Since 2001 with the participation in the IAEA Tissue Banking Programme, Quality System Management has been implemented in the NMTB. New bio-production for radiosterilized tissues for the first time and improved procedures were carried out. As a result an increased production of high-quality tissues was obtained and distributed for clinical use. 相似文献
137.
Linares JA Campos ML Goldraij A 《Prostaglandins, leukotrienes, and essential fatty acids》2003,69(1):39-43
A 25-day dietary restriction (50% of the normal diet) produce a fall in the production of 14CO2 from 14C-glucose in rats isolated uteri. The addition of 10 or 20 ngml(-1) interleukin 1alpha (IL-1alpha) or interleukin 2(IL-2) to the Krebs-Ringer bicarbonate solution medium stimulates glucose metabolism in uteri from underfed rats. Such concentrations are not effective in control rats. The addition of Nomega-nitro-L arginine methyl ester--an inhibitor of both the constitutive and inducible forms of nitric oxide synthase (NOS)--and of aminoguadinine--a preferential inhibitor of the inducible form of NOS--block such stimulation. In other experiments, the addition to the medium of arginine-a substrate for the formation of nitric oxide-increases interleukin stimulation of glucose metabolism, which is blocked by NOS inhibitor. At the same time, NS-398--a selective inhibitor of inducible cyclooxygenase (COX)--eliminates the interleukin metabolism stimulation. We conclude that IL-1alpha and IL-2 produce an increase of glucose metabolism in uteri isolated from underfed rats. Nitric oxide produced by the inducible form of NOS mediates the interleukins-induced glucose metabolism stimulation with the participation of inducible COX. 相似文献
138.
Vásquez Tsuji O Rodríguez Herrera R Campos Rivera T Mora Tiscareño MA Aguirre Maldonado E Yamazaki Nakashimada MA Valencia Rojas S Martínez Barbosa I 《Boletín chileno de parasitología》2001,56(1-2):16-21
We present the case of a four-year-old boy with a history of repeated upper respiratory tract infections and pyoderma. He presented fever, seizures, inability to talk, loss of swallowing, fine tremor in the upper extremities; positive bilateral Babinski reflex and quadriparesis. The diagnosis of Bruton's disease and generalized microporidiosis was based on immunologic analysis, smear tests with chromotrope R2 stain and indirect immunofluorescense with monoclonal 3B6 antibody for Encephalitozoon species in samples of spinal fluid, bronchial and paranasal sinus aspirates and stool, which were all positive. The patient was treated with albendazol during 72 days; he left the hospital in a good condition, walking, talking and able to swallow. His laboratory test controls were negative; he is followed up in the outpatient department. 相似文献
139.
Casalino-Matsuda SM Linares JA Campos LM Goldraij A 《Prostaglandins, leukotrienes, and essential fatty acids》2000,63(6):337-341
The effects of insulin on the metabolism of U14C-glucose in uteri isolated from ovariectomized and non-ovariectomized rats receiving a restricted diet (50% of the normal food intake) for 25 days, were studied. As a result of food restriction, the production of 14CO2 diminishes in intact rats, while results are reversed in ovariectomized ones. Various concentrations of insulin were added to the medium, but only 0.50 IU. ml(-1)was effective in increasing glucose metabolism in intact rats receiving a restricted diet; neither underfed castrated animals nor control ones receiving a normal diet, reacted to this concentration. The increase of 14CO2 produced by insulin is not affected by acetyl salicylic acid. Insulin does not alter the effect of underfeeding over arachidonic acid metabolism. On the contrary, the increase in glucose metabolism was blocked by N(G)methyl-L-arginine or by hemoglobin, increased with the addition of L arginine and is not affected by acetyl salicylic acid. Hemoglobin and L-arginine show no effects without insulin. We can conclude that the stimulating effect of insulin on glucose metabolism in uteri isolated from intact rats subjected to dietary restriction, is nitric oxide dependent. 相似文献
140.