PubMed Health⌕ Search

Biomedical subjects

L Carrillo

Publications and source records attributed to L Carrillo.

At least 19 recordsLinked to original sources

Hydrolytic properties of crude alpha-L-rhamnosidases produced by several wild strains of mesophilic fungi.

AIMS: Observation of the dependence of alpha-L-rhamnosidase activity on pH and temperature and the capability to hydrolyse concentrated naringin solutions and hesperidin suspensions of enzyme complexes produced by several fungi. METHODS AND RESULTS: The enzymes were produced by several wild strains of mesophilic fungi grown in liquid media containing rhamnose as sole carbon source. The properties and their ranges of values measured were as follows: (i) optimum pH, 3.5-6.5; (ii) optimum temperature, 50-65 degrees C; (iii) hydrolysis of supersaturated 100 g l(-1) naringin solutions, 45-100% and (iv) hydrolysis of hesperidin suspensions, 6-35%. CONCLUSIONS: Some alpha-L-rhamnosidase enzymes hydrolysed supersaturated naringin solutions with a high yield. The enzyme produced by Fusarium sambucinum 310 showed good activity even at pH 10. SIGNIFICANCE AND IMPACT OF THE STUDY: Crude enzymes with possible utilization as catalysts for the manufacture of hydrolysis products of the flavonoid glycosides were found.

Aspergillus↗

Aziridine ring-opening reactions with chiral enolates. Stereocontrolled synthesis of 5-substituted-3-methyl-pyrrolidin-2-ones.

A procedure for performing stereocontrolled aziridine ring-opening reactions with chiral enolates derived from (S,S)-(+)-pseudoephedrine amides has been developed leading to gamma-aminoamides in good yields. The diastereoselectivity of the reaction becomes controlled by the presence of the chiral auxiliary on the enolate, although the stereogenic center contained in the structure of the aziridine has a striking influence on the stereochemical course of the reaction which results in the presence of the corresponding matched and mismatched combinations. Besides, the sense of the asymmetric induction of the chiral auxiliary has resulted to be the opposite to the one found with other type of electrophiles, although it is in good agreement with the trend observed in the reaction of the same kind of enolates with epoxides. Finally, the obtained gamma-aminoamide adducts were converted into enantiopure gamma-amino acids, gamma-aminoesters, and pyrrolidin-2-ones using easy to perform and high yielding reactions.

Journal Article↗

Asymmetric synthesis of beta-substituted alpha-methyl-beta-amino esters by Mannich reaction of (S,S)-(+)-pseudoephedrine acetamide derived enolate with imines.

[reaction: see text]. The reaction of an (S,S)-(+)-pseudoephedrine acetamide based enolate with several imines afforded smoothly and with full stereochemical control a series of beta-substituted alpha-methyl-beta-aminoamides that upon hydrolysis/esterification afforded the corresponding beta-aminoester derivatives in good yields and in almost enantiomerically pure form.

Acetamides↗

Asymmetric aldol reactions using (S,S)-(+)-pseudoephedrine-based amides: stereoselective synthesis of alpha-methyl-beta-hydroxy acids, esters, ketones, and 1,3-Syn and 1,3-anti diols

A very efficient method for performing stereoselective aldol reactions is reported. The reaction of (S, S)-(+)-pseudoephedrine-derived propionamide enolates with several aldehydes yielded exclusively one of the four possible diastereomers in good yields, although transmetalation of the firstly generated lithium enolate with a zirconium(II) salt, prior to the addition of the aldehyde, is necessary in order to achieve high syn selectivity. The so-formed syn-alpha-methyl-beta-hydroxy amides were transformed into other valuable chiral nonracemic synthons such as alpha-methyl-beta-hydroxyacids, esters, and ketones. Finally, a stereocontrolled reduction procedure starting from the so-obtained alpha-methyl-beta-hydroxy ketones has been developed allowing the synthesis of either 1,3-syn- or 1,3-anti-alpha-methyl-1,3-diols in almost enantiopure form by choosing the appropriate reaction conditions.

Journal Article↗

[The self-measurement of blood glucose and mean glycemias in patients with diabetes mellitus].

OBJECTIVE: To assess the influence that self-measurement of capillary blood glucose (SMBG) has on glucaemia control in patients with diabetes mellitus. DESIGN: Quasi-experimental before and after study. SETTING: Semi-urban health centre. PATIENTS: All diabetic patients, with at least two years of evolution, who used reactive strips for SMBG in 1996. MEASUREMENTS AND MAIN RESULTS: Mean values of base glucaemia in the SMBG study year were compared with those of the year before in 85 patients, 33 men and 52 women, with average age 62.38. Thirteen were type 1 and 72 type 2 diabetics, with a mean 15.61 years of evolution of the disease. A drop of -11.47 mg/dl (SD 44.32) was observed, which was significant (p < 0.05, CI 95%) in the overall results. In all the subgroups, except those treated with non-pharmacological measures, there were drops, ranging between -2.17 mg/dl and -17.01 mg/dl, which were significant in women, in patients with type 2 diabetes, in those who had received health education and in those treated with non-pharmacological measures plus insulin. CONCLUSIONS: Despite the limitations of this kind of study, our findings point towards a slightly better control of glucaemia levels in diabetic patients after SMBG. It is very doubtful whether it signifies any real improvement in managing the illness.

Adolescent↗

Results of 12 years' combined maternal serum alpha-fetoprotein screening and ultrasound fetal monitoring for prenatal detection of fetal malformations in Havana City, Cuba.

Progressively since 1982 and as part of a nationwide programme for the diagnosis and prevention of genetic diseases, maternal serum alpha-fetoprotein (MS-AFP) screening and ultrasound fetal monitoring has been implemented in all pregnant women in Cuba. In Havana City, 328,983 pregnant women underwent MS-AFP screening between 15 and 19 weeks of gestational age. With a cut-off level of > or = 2 multiples of the normal median (MOM), 1767 amniocenteses were carried out to determine the levels of amniotic fluid AFP and 685 malformed fetuses were diagnosed. By ultrasound fetal monitoring, an additional 686 malformed fetuses were detected. As a result of the programme, the birth prevalence of neural tube defects has fallen by 90 per cent.

Amniotic Fluid↗

Epidemiology of hepatitis B vaccine acceptance among urban paramedics and emergency medical technicians.

BACKGROUND: The epidemiologic pattern of hepatitis B vaccination acceptance has not been thoroughly examined in medical first responders. METHODS: A blood-borne pathogen questionnaire was administered to 255 paramedics and emergency medical technicians (EMTs) in a large, urban fire department. RESULTS: The overall prevalence of hepatitis B vaccination was 78%. The most frequently cited reason for not getting vaccinated was fear of contracting the hepatitis B virus from the vaccination (26%). Vaccination scheduling difficulties (23%) and lack of time to get vaccinated (20%) were also cited. Increased age, being an EMT, and not having obtained the rank of officer were independently and significantly associated with not having been vaccinated. CONCLUSIONS: Educational campaigns for medical first responders are needed to increase vaccination compliance, with a special emphasis on older workers and EMTs. Administrative barriers, such as vaccination scheduling difficulties, should also be addressed.

Adult↗

Bloodborne pathogens risk and precautions among urban fire-rescue workers.

Health care workers are exposed to various infectious agents that can lead to disease transmission during patient care. Emergency first-responders, paramedics, and emergency medical technicians (EMTs) are a subgroup of health care workers particularly at risk for occupational exposure to bloodborne pathogens. The Centers for Disease Control and Prevention has recommended universal precautions to prevent occupational transmission of bloodborne pathogens among health care workers. This cross-sectional study evaluates risks and behaviors for occupational exposure to bloodborne pathogens among urban paramedics and EMTs in Dade County, Florida. Reported exposure via multiple routes was common, especially among paramedics. Knowledge of universal precautions was high, but reported practices were suboptimal because of inadequate information, as well as logistical and access issues. Additional research, administrative effort, and regulation are needed to increase the application of universal precautions in the prehospital setting.

Adult↗

Bioimpedance monitoring of rehydration in cholera.

Measurement of bioimpedance (BI) is a simple non-invasive technique that relies on the different conductivity of tissues to define body composition and can be easily adapted to automated monitoring. We assessed the accuracy of BI in monitoring rehydration and acute fluid fluxes in 35 Peruvian cholera patients. Patients were monitored throughout the acute phase of diarrhoea and followed up at 3 and 10 days. BI was compared with other objective measures of dehydration including packed cell volume, serum protein, and calculated fluid balance. BI rapidly detected inadequate treatment and acute fluid flux, correlating highly with intravascular hydration as measured by serum protein and packed cell volume. BI values during dehydration were significantly raised compared with 10-day convalescent values and age-matched controls (p < 0.05). We also encountered an unexpected difference in the bioelectrical response to dehydration and rehydration between sexes. We conclude that BI has uses in monitoring dehydrated patients, in oral rehydration trials, and in physiological studies.

Acute Disease↗

Environmental and genetic effects on preweaning growth performance of hair sheep in Mexico.

Data on 4,754 lambs born from Pelibuey (PB) and Barbados Blackbelly (BB) ewes collected over 9 years at the Mococha Experimental Centre in Yucatan, Mexico, were used to determine environmental, dam-breed and sire-breed effects on birth weight (BW), weaning weight (WW) and average daily gain (ADG). Effects of year and season of birth, sex of the lamb, type of birth, breed of dam, breed of sire, their interaction and ewe body weight were included. Heritabilities were estimated for each breed. Season of lambing was a significant source of variation on WW and ADG. Male lambs weighed more than female lambs at birth and weaning. Single born lambs were heavier than twins and triplets. Lambs born from PB dams were heavier and grew faster than those born from BB dams. Heritabilities of BW, WW and ADG for the PB breed were 0.16 +/- 0.04, 0.12 +/- 0.03 and 0.11 +/- 0.03, respectively and 0.04 +/- 0.07, 0.17 +/- 0.09 and 0.15 +/- 0.08 for the BB breed. Heterosis values were close to zero.

Animals↗

Evidence that human placenta is a site of sex hormone-binding globulin gene expression.

The presence of an androgen-binding component in placenta was investigated in vitro using a tissue culture system of human placental explants. Explants of trophoblastic tissue from normal term placentas were kept in culture under appropriate conditions for at least 48 h in a serum-free medium. The existence of an androgen-binding protein was explored by binding assays, immunohistochemistry studies and Northern blot analyses of placental mRNA. Steady-state polyacrylamide gel electrophoresis and Scatchard plot analyses revealed the presence of a high affinity specific binding component for 5 alpha-dihydrotestosterone in cultured placenta. Immunohistochemical studies performed on intact placenta and on Percoll-gradient purified trophoblastic cells demonstrated the presence of specific immunoreactivity in the cytoplasm of syncytial cells. Northern blot analyses of placental mRNA showed a single hybridizable 32P-labeled human sex hormone-binding globulin (SHBG) cDNA band of approx. 1.6 kb which was identical in size to that obtained with liver mRNA. The results strongly suggest the placenta as an origin of SHBG and point out this tissue as an additional site of SHBG synthesis during pregnancy.

Blotting, Western↗

Neonatal androgen influences sexual motivation but not the masculine copulatory motor pattern in the rat.

Masculine sexual responses displayed by female rats, were compared to those of males. Twenty-five percent of females mounted and 19% showed intromission behavior, but none of them displayed the ejaculation pattern. Masculine sexual behavior was displayed in all stages of the estrous cycle. Accelerometric and spectrum frequency analysis of electrical signals generated by pelvic movements during mounting and intromission showed that these patterns were identical in both sexes excepting that mount duration in females was longer than in males. Neonatal androgenization of females increased the display of intromission patterns. Treatment of ovariectomized rats, androgenized or not, with either estradiol benzoate or testosterone propionate stimulated masculine sexual behavior. The ejaculatory pattern was only displayed by neonatally androgenized females. Mounting and intromission motor patterns of females under steroid treatment, and ejaculations of neonatally androgenized females, were similar to those of males. The results show that the organization of the movements involved in masculine sexual behavior in rats are identical in both sexes, thus suggesting that the neural circuits controlling these behaviors could be identical. Neonatal or postpubertal androgen in the rat influences the frequency with which male-like responses are displayed, but not their temporal (frequency, rhythm) or dynamic (acceleration, vigour) characteristics.

Animals↗