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C Ramirez

Publications and source records attributed to C Ramirez.

At least 19 recordsLinked to original sources
PubMed2006

True impact of the indication of cirrhosis and the MELD on the results of liver transplantation.

UNLABELLED: Our Aim was to determine the impact of cirrhosis and the preoperative MELD score on the immediate postoperative mortality and hospital stay as well as survival at 1, 5, and 8 years in liver transplantation. MATERIALS AND METHODS: Transplanted cirrhotic patients were selected who did not display some of the main known risk factors affecting recipient. Donor and surgical technique were included in this analysis. These exclusion criteria for recipient factors were emergency transplants and retransplants; for donor factors, age over 60 years, ischemia time over 10 hours, and moderate or severe steatosis on back-bench biopsy; and for surgery, prior complex upper abdominal surgery (mainly derivative and gastroduodenal surgery). Among 340 total liver transplants including 16 retransplants performed from March 1997 to December 2005, 197 patients met the selection criteria. The mean age of the recipients was 52 years (17-67) and the donors, 39 years (11-60). The transplant indication was cirrhosis in all cases: HCV in 69 cases (35%); alcohol in 55 (28%); hepatocarcinoma in 38 (19%); HBV in 19 (10%); PBC in 8 (4%), and other etiologies in 8 cases (4%). The MELD scores were divided as group 1, <10 points (33 cases = 17%); group 2, 10 to 18 points (136 cases = 69%); and group 3, >18 points (28 cases = 14%). The statistical analysis was performed with SPSS 11.0. RESULTS: Postoperative mortality (up to 3 months) was 16 cases (8%). The median ICU and hospital stays were 3 and 13.5 days, respectively. Overall survivals at 1, 5, and 8 years were 89%, 80%, and 77%, respectively. The survival for the same periods according to MELD group was 97%, 97%, and 97% for group 1; 87%, 76%, and 72% for group 2; and 85%, 81%, and 81% for group 3 (P = NS). The survival according to the three main indications at 1, 5, and 8 years was: HCV, 91%, 80%, and 80%; alcohol, 87%, 80%, and 71%; and hepatocarcinoma, 84%, 80%, and 80% (P = NS). No significant differences were observed among early deaths between MELD groups or transplant indications. CONCLUSIONS: In a favorable liver transplant setting including acceptable donors, absence of prior complex abdominal surgery in the recipient, and nonemergency transplants, neither the cause of the cirrhosis nor its severity, as measured preoperatively by the MELD, were predictive of early postoperative death or long-term survival.

Adolescent↗
PubMed2006

[Myasthenia gravis and pregnancy: clinical course and management of delivery and the postpartum phase].

OBJECTIVES: To study influences of pregnancy on the time-course of myasthenia gravis (MG) and of MG on pregnancy, delivery, postpartum and newborn. METHODS: We retrospectively collected data from 100 women affected with MG, hospitalized between 1994 and 2003 in departments of Neurology of Lille University Hospital. RESULTS: Eighteen patients had a total of 36 pregnancies, occurring 7.2 years on average after MG onset. MG exacerbation occurred in 7 patients (26 percent) during pregnancy and in 4 (14.8 percent) during postpartum. One patient died of acute respiratory failure during postpartum. Delay between the onset of MG and pregnancy was the only variable significantly associated with MG exacerbation: 5.8 years when exacerbation and 9.5 years when no exacerbation (p=0.03). Seven miscarriages, two therapeutic abortions and no death at birth were reported. Levels of anti-acetylcholine receptor antibodies were abnormal in 3 of 27 newborns (11 percent), but only one (3.7 percent) developed seronegative transient neonatal myasthenia gravis. DISCUSSION: During pregnancy, the clinical course of MG is variable but exacerbations were associated with a shorter delay between MG diagnosis and pregnancy. The risk of transient neonatal myasthenia gravis is relatively small but exists even when the parturient has stable MG without elevated levels of anti-acetylcholine receptor antibodies. CONCLUSION: Our study confirms pregnancy is more difficult to manage at the beginning of MG. Given the unpredictable course of MG during pregnancy, we recommend women affected with MG to begin a pregnancy when the disease is stable.

Abortion, Therapeutic↗
PubMed2004

[Pure subacute pandysautonomia: an assessment of treatment with intravenous polyvalent immunoglobulins].

INTRODUCTION: Acute or sub-acute pure dysautonomia is uncommon. We report a case of sub-acute pure pandysautonomia with favorable outcome after intravenous immunoglobulin therapy. CASE REPORT: A 29-year-old right-handed student, with an uneventful medical history presented, for one month, bilateral loss of visual acuity and digestive disorders, associating diarrhea, vomiting and anorexia. Physical examination revealed bilateral intrinsec oculomotor nerve palsy, a dryness syndrome and severe orthostatic hypotension. Ophthalmologic examination showed bilateral diffuse parasympathic impairment associating an Argyll Robertson pupil and full pupil light reflex abolition. Elevated protein level (0.93g/l) was the only cerebrospinal fluid anomaly. Serum tests were negative for anti-gangliosides antibodies. The patient improved slowly after two series of intravenous immunoglobulin infusions. CONCLUSION: Clinical course and laboratory findings suggest that acute or sub-acute pure pandysautonomia events are likely to be related to acute polyradiculoneuritis. Therefore intravenous polyvalent immunoglobulin infusions should be attempted, even if their efficacy needs to be confirmed.

Acute Disease↗
PubMed2004

[Infectious myelopathies: clinical, serological, and prognostic patterns].

INTRODUCTION: Serological confirmation of an infectious acute myelitis injury is difficult to confirm as it is sometimes due to a post-infectious etiology. OBJECTIVES: The aim of this study was to define the clinical, biological and prognostic patterns of infectious myelitis. PATIENTS AND METHODS: This retrospective study included 153 subjects hospitalized in the department of neurology between 1993 and 2002 for treatment of a noncompressive acute myelopathy. Biological confirmation of recent infection was obtained in 12 patients (8 p. 100). RESULTS: An infectious syndrome, beginning prior to the neurological symptoms, was found in 67 percent of patients. The clinical symptoms were severe with loss of sensoromotor and sphincter functions and ascending spinal cord dysfunction (acute transverse myelopathy). Spinal cord MRI showed extended centromedullar high intensity signals with rapid and complete regression. CSF analysis cell count was above 30/mm3 with hyperproteinorachia, in 75 percent and 58 percent of patients respectively. CSF electrophoresis did not detect oligoclonal bands. Clinical outcome was good in all patients except one, however sphincter disorders recovered slowly. DISCUSSION: Our study illustrates a stereotypical clinical, biological and prognostic pattern for infectious acute myelitis. These findings contribute significantly to therapeutic decision making and establishing prognosis at the initial phase of acute myelopathy.

Adolescent↗
PubMed2003

Quasi-collective motion of nanoscale metal strings in metal surfaces.

Mass transport processes on metal surfaces play a key role in epitaxial growth and coarsening processes. They are usually described in terms of independent, statistical diffusion and attachment/detachment of individual metal adatoms or vacancies. Here we present high-speed scanning tunnelling microscopy (video-STM) observations of the dynamic behaviour of five-atom-wide, hexagonally ordered strings of Au atoms embedded in the square lattice of the Au(100)-(1x1) surface that reveal quasi-collective lateral motion of these strings perpendicular to as well as along the string direction. The perpendicular motion can be ascribed to small atomic displacements in the strings induced by propagating kinks, which also provides a mechanism for the exchange of Au atoms between the two string ends, required for motion in string direction. In addition, quasi-one-dimensional transport of Au adatoms along the string boundaries may contribute to the latter phenomenon according to density functional calculations.

Computer Simulation↗
PubMed2003

Cross sectional survey of perpetrators, victims, and witnesses of violence in Bogotá, Colombia.

OBJECTIVES: To establish the prevalence and distribution of witnesses, victims, and perpetrators of different types of violence in the general population and the proportion of victims consulting health services or reporting the incident to authorities. METHODS: Cross sectional survey of a random sample of 3007 inhabitants between the ages of 15 and 60 in the city of Bogotá, Colombia, in 1997, based on a face to face interview. RESULTS: Age adjusted past year prevalence of witnesses, victims, and perpetrators of physical aggression was 61%, 27%, and 27%, respectively, while lifetime prevalence of witnesses, victims, and perpetrators of assault with a weapon in this population reached 70%, 55%, and 5.8%. Between 11% and 67% of the victims consulted a health service and less than 32% reported the incident to an authority. Those involved in most types of physical violence tended to be young, male, from lower middle social classes, with some degree of secondary education, and single or divorced. CONCLUSIONS: Prevalence of witnesses and victims of violence in this sample appears to be high, while perpetrators constitute a small proportion. Violence is not equally distributed throughout the population suggesting the possibility of identifying a population at higher risk for the development of intervention programmes.

Adolescent↗
PubMed2001

Management of cancer of the supraglottis.

We present the results of a retrospective study of 903 patients treated with conservation surgery for carcinoma of the supraglottic larynx so we can evaluate our management of supraglottic cancer with different types of surgery. In 301 patients, an extended supraglottic laryngectomy was performed. The recent selective use of transoral laser resection appears to be a rational approach. The 5-year uncorrected survival was 84%, 81%, 76%, and 55% for stages I, II, III, and IV, respectively. The most common site for local-regional failure was the cervical lymphatics. The percentage of occult disease in the NO neck was 21% and epilaryngeal supraglottic location, locally advanced and GIII tumors have a higher frequency of lymph node involvement. There were no differences between comprehensive and anterolateral elective neck dissections. A bilateral elective neck dissection is recommended. In histologically positive neck disease, the survival rates were better with postoperative radiotherapy only in cases of extracapsular spread.

Carcinoma↗
PubMed2000

Early histological maturation in the hippocampus of the guinea pig.

The vesicular zinc-rich synaptic systems of the principal neurons of the hippocampus are well developed in newborn guinea pigs, a precocial species. In addition, alvear and fimbrial myelinated fibers as well as significant inhibitory interneurons (i.e. somatostatin, parvalbumin and opioid immunoreactive hippocampal interneurons) are also well developed. On the contrary, neither vesicular zinc synapses nor myelinated fibers nor the above mentioned immunoreactive interneurons are detectable in newborn specimens of other related altricial species such as rats or rabbits. These data suggest that early maturation of a highly integrative center related to cognitive map building such as the hippocampus is characteristic of precocial species.

Animals↗
PubMed2000

Identification of tuberculosis in cattle slaughtered in Mexico.

OBJECTIVES: To determine epidemiologic factors associated with tuberculosis (TB) in dairy cattle slaughtered in 6 important regions for milk production in Mexico. ANIMALS: 2,500 cattle. PROCEDURE: Tissue specimens with lesions typical of TB were obtained during routine inspection of carcasses at abbatoirs between July 1996 and January 1997. Infection with Mycobacterium organisms was confirmed by histologic examination and bacteriologic culture. Species identification was made by use of selective growth medium, conventional biochemical tests, and radiometric procedures. Epidemiologic information for affected cattle was obtained by personal interviews with cattle dealers and owners. RESULTS: 400 (16%) of 2,500 cattle carcasses had gross lesions typical of TB. Of the 400 infected cattle, 336 (84%) had lesions in > or = 1 lymph node. Infection was confirmed in 87% of cattle with gross lesions by histologic examination, in 77% by bacteriologic culture at a laboratory in the United States, and in 59% by bacteriologic culture at a laboratory in Mexico. Most cattle were adult females in fair to good body condition that came from large herds (> 500 cattle) and were not included in the Mexican TB control program. CONCLUSIONS AND CLINICAL RELEVANCE: Mean prevalence of lesions typical of TB in dairy cattle at 6 locations in Mexico was 16%. Mycobacterium infection was confirmed by various techniques in most lesions. Recognition of typical gross lesions at slaughter may expedite TB control procedures.

Abattoirs↗
PubMed2000

Molecular epidemiologic analysis of Mycobacterium bovis isolates from Mexico.

OBJECTIVE: To assess phylogenetic relationships among Mycobacterium bovis isolates by use of random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) fingerprinting and to relate genetic profiles of isolates to epidemiologic characteristics. ANIMALS: 400 cattle with tuberculosis. PROCEDURE: Mycobacterium bovis was isolated from various organs of cattle slaughtered in 6 geographic regions of Mexico. Most cattle were adult Holsteins from large herds that did not participate in a tuberculosis control program. Four random primers and 2 selected primers were used in RAPD-PCR fingerprinting of 88 isolates. Pairwise genetic distance between isolates was obtained and subjected to cluster analysis with bootstrapping to test for levels of support. RESULTS: 98 different fragments were obtained; there was broad genetic diversity among isolates, and each isolate had a unique RAPD-genotype, including those originating from the same herd. Clustering by geographic location, affected organ, or severity of lesion was not detected. Linkage disequilibrium analysis suggested that M. bovis was highly clonal and that mutations develop at a rapid rate among isolates. CONCLUSIONS AND CLINICAL RELEVANCE: Use of RAPD-PCR could not differentiate M. bovis isolates by epidemiologic characteristics or identify common sources of infection.

Animals↗
PubMed2000

Decisions on child care: do sex and sexual orientation matter?

This experiment on person perception used a role-playing methodology to examine whether a target individual's sex and sexual orientation influence perceived abilities as a child care worker. Men and women (N = 78) role played the part of a parent who has placed an advertisement for a full-time babysitter. They received information about a male or female, heterosexual or homosexual applicant (randomly assigned). Although participants preferred to hire (and felt more comfortable leaving their children with) a heterosexual woman than any other type of applicant, they believed that homosexual men and women were as knowledgeable about aspects of child care, e.g., nutrition, first aid, as their heterosexual peers. The least preferred child care worker was a heterosexual man, perhaps because such a target is inconsistent with traditional sex-role expectations.

Adult↗
PubMed1999

Analysis of growth kinetics by division tracking.

Cell division tracking using fluorescent dyes, such as carboxyfluorescein diacetate succinimidyl ester, provides a unique opportunity for analysis of cell growth kinetics. The present review article presents new methods for enhancing resolution of division tracking data as well as derivation of quantities that characterize growth from time-series data. These include the average time between successive divisions, the proportion of cells that survive and the proliferation per division. The physical significance of these measured quantities is interpreted by formulation of a two-compartment model of cell cycle transit characterized by stochastic and deterministic cell residence times, respectively. The model confirmed that survival is directly related to the proportion of cells that enter the next cell generation. The proportion of time that cells reside in the stochastic compartment is directly related to the proliferation per generation. This form of analysis provides a starting point for more sophisticated physical and biochemical models of cell cycle regulation.

Cell Count↗
PubMed1999

Carcinoma of cervix, the King Faisal Specialist Hospital & Research Center experience--the need for screening for cervical cancer in developing countries.

The King Faisal Specialist Hospital and Research Center opened in 1975 to provide specialized medical treatment to the citizens of Saudi Arabia and to promote prevention of disease through research and education. It is a national and middle eastern tertiary care hospital for oncology and a principle center for radiation therapy in Saudi Arabia. In this retrospective study, 504 patients with carcinoma of the cervix were analysed. Of the 504 patients, 410 received treatment with curative intent, which comprised radical surgery alone, radical radiation alone or combination surgery and radiation. The overall 3, 5 and 10 years survival of all 504 patients was 64%, 55% and 40%, respectively and for 410 patients treated with curative intent it was 74%, 61% and 51%, respectively. Multivariate analysis, using the Cox regression method, showed that the stage of the disease is the only significant prognostic factor influencing relapse-free survival. Stage for stage, treatment outcomes at King Faisal Specialist Hospital and Research Center match those achieved in the First world, but two-thirds of patients (rather than one-third) present with advanced disease at diagnosis. Therefore, any improvement in overall outcomes will require earlier diagnosis, achievable only through an effective screening program in the Kingdom of Saudi Arabia and similarly in the other Third world countries where patients present with advanced stage disease.

Combined Modality Therapy↗
PubMed1997

Zinc-positive presynaptic boutons of the rabbit hippocampus during early postnatal development.

The evolution of vesicular zinc-containing boutons in the developing rabbit hippocampus has been studied during early postnatal life using the selenite-Danscher histochemical method. By P3, large immature mossy fiber boutons with labeled synaptic vesicles were seen in the hilus of the dentate gyrus and in the stratum lucidum of the CA3-CA4 hippocampal areas. After P5, smaller boutons with labeled vesicles were identified in the stratum oriens and stratum radiatum of all hippocampal areas, and even transiently in the stratum lacunosum of P6 animals. Vesicular zinc-containing boutons increased in number and underwent ultrastructural maturation; light microscope densitometric-volumetric measurements were used to quantify their presence in every hippocampal lamina. Electron microscope stereologic analysis permitted accurate estimation of the actual numbers along early postnatal development. Three main phases of zinc-positive bouton growth were detected during the first postnatal month. The first phase, starting at P5, is characterised by an abrupt rise in vesicular zinc content which at P8-P9 begins to decrease. The second phase is characterised by a consistent rise in vesicular zinc content from P10 to P12 to a level which is maintained until P18; this steady period is the result of partial and sequential elimination of zinc-positive boutons in some areas (i.e. oriens of CA3 by P11, radiatum of CA3 by P13, and radiatum of CA1 and lucidum of CA3 by P15) while they continue to increase in other areas. The final phase is a continuous increase to almost adult levels.

Animals↗