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L Castillo

Publications and source records attributed to L Castillo.

At least 37 records · Page 2Linked to original sources
PubMed2001

Phylogenetic analysis of dengue-3 viruses prevalent in Guatemala during 1996-1998.

Dengue is an acute viral disease transmitted by the Aedes aegypti mosquito which is present in most tropical urban areas of the world. There are four antigenically distinct serotypes, designated dengue-1 (DEN-1), dengue-2 (DEN-2), dengue-3 (DEN-3) and dengue-4 virus (DEN-4). In this study, we determined the serotypes of dengue viruses isolated in Guatemala in 1995-1998, and found that DEN-3 viruses appeared in 1995 and became predominant in the following three years. We then sequenced cDNAs from fifteen DEN-3 isolates recovered during 1996-1998. From the nucleic acid sequences and previously determined DEN-3 sequences, a phylogenetic tree was constructed using the neighbor joining method. The tree indicated that all fifteen isolates and other DEN-3 viruses isolated in Sri Lanka, India, Samoa and Mozambique formed subtype III. More than two decades ago, DEN-3 virus was prevalent in the Caribbean, but the isolates obtained at that time belonged to subtype IV. Therefore, we concluded that the 1996-1998 dengue epidemic in Guatemala was caused by DEN-3 strains, imported from a tropical area of Asia or Africa or from a Pacific island.

DNA, Complementary↗
PubMed2001

Longterm survival in acute rhinocerebral mucormycosis with giant cell arteritis and foreign body granulomas.

A case of rhinocerebral mucormycosis occurring in a 41-year-old man with insulin-treated diabetes mellitus is reported. Microscopically, biopsy samples obtained from the left ethmoid and middle turbinate sinuses contained fungi that formed mycotic granulomas associated with multinucleate giant cell arteritis. The multinucleate giant cells contained broad, infrequently septate hyphase consistent with mucormycosis. The patient received surgical debridement with extenteration of the left orbit, and intravenous liposome-encapsulated amphotericin B. After 12 months, examination of the patient revealed complete healing. Multinucleate giant cell granulomas and arteritis are only exceptionally associated with rhinocerebral mucormycosis, but these histologic findings may be correlated with a progressive disease with better prognosis.

Acute Disease↗
PubMed2001

Cysteine metabolism and whole blood glutathione synthesis in septic pediatric patients.

OBJECTIVE: To investigate whole body in vivo cysteine kinetics and its relationship to whole blood glutathione (GSH) synthesis rates in septic, critically ill pediatric patients and controls. DESIGN: Prospective cohort study. SETTING: Multidisciplinary intensive care unit and pediatric inpatient units at a children's hospital. PATIENTS: Ten septic pediatric patients and ten controls (children admitted to the hospital for elective surgery). INTERVENTIONS: Septic patients (age, 31 months to 17 yrs) and controls (age, 24 months to 21 yrs) received a 6-hr primed, constant, intravenous tracer infusion of l-[1-13C]cysteine. Blood samples were obtained to determine isotopic enrichment of plasma cysteine and whole blood [1-13C]cysteinyl-glutathione by gas-chromatography mass spectrometric techniques. The plasma flux and oxidation rate of cysteine and the fractional and absolute synthesis rates of GSH were determined. Septic patients received variable protein and energy intake, as per routine clinical management, and controls were studied in the early postabsorptive state. MEASUREMENTS AND MAIN RESULTS: Plasma cysteine fluxes were increased in the septic patients when compared with the controls (68.2 +/- 17.5 [sd] vs. 48.7 +/- 8.8 micromol x kg(-1) x hr(-1); p <.01), and the fraction of plasma cysteine flux associated with oxidative disposal was similar among the groups. The absolute rates of GSH synthesis in whole blood were decreased (p <.01) in the septic patients (368 +/- 156 vs. 909 +/- 272 micromol x L(-1) x day(-1)). The concentration of whole blood GSH also was decreased in the septic group (665.4 +/- 194 vs. 1059 +/- 334 microM; p <.01) CONCLUSIONS: Whole blood glutathione synthesis rates are decreased, by about 60%, in critically ill septic children receiving limited nutritional support. Plasma cysteine fluxes and concentration of cysteine were increased in the septic patients, suggesting a hypermetabolic state with increased protein breakdown. The mechanisms whereby GSH synthesis rates are decreased in these patients are probably multifactorial, presumably involving an inflammatory response in the presence of limited nutritional support. The role of nutritional modulation and the use of cysteine prodrugs in maintaining GSH concentration and synthesis remain to be established.

Adolescent↗
PubMed2001

Arginine and ornithine kinetics in severely burned patients: increased rate of arginine disposal.

Arginine serves multiple roles in the pathophysiological response to burn injury. Our previous studies in burn patients demonstrated a limited net rate of arginine de novo synthesis despite a significantly increased arginine turnover (flux), suggesting that this amino acid is a conditionally indispensable amino acid after major burns. This study used [15N2-guanidino-5,5-2H2]arginine and [5-13C]ornithine as tracers to assess the rate of arginine disposal via its conversion to and subsequent oxidation of ornithine; [5,5-2H2]proline and [5,5,5-2H3]leucine were also used to assess proline and protein kinetics. Nine severely burned patients were studied during a protein-free fast ("basal" or fast) and total parenteral nutrition (TPN) feedings. Compared with values from healthy volunteers, burn injury significantly increased 1) fluxes of arginine, ornithine, leucine, and proline; 2) arginine-to-ornithine conversion; 3) ornithine oxidation; and 4) arginine oxidation. TPN increased arginine-to-ornithine conversion and proportionally increased irreversible arginine oxidation. The elevated arginine oxidation, with limited net de novo synthesis from its immediate precursors, further implies that arginine is a conditionally indispensable amino acid in severely burned patients receiving TPN.

Adult↗
PubMed2001

Health status and health-related quality of life in survivors of cancer in childhood in Latin America: a MISPHO feasibility study.

Cancer is an increasing cause of disease-related death in childhood within developing countries, where the great majority of the world's children reside. The improving prospects for survival in such children, and the corresponding challenge of undertaking economic evaluations of related health interventions, provide a stimulus to study the health-status and health-related quality of life in survivors of cancer in childhood in Latin America. Spanish language versions of questionnaires for proxy assessors, based on the Health Utilities Index (HUI), were used to elicit responses from parents and physicians. The HUI is a family of multi-attribute, generic, preference-linked measures of health status and health-related quality of life that are reliable, responsive and valid, and have been used previously in pediatric oncology. Valid responses were received from 178 parents and 144 physicians in 6 centres in 4 countries (Cuba, Honduras, Colombia and Uruguay). For children with acute lymphoblastic leukemia the major morbidity burdens were in the attributes of emotion, cognition and pain. The overall burden of morbidity was greater in children with non-Hodgkin's lymphoma. In survivors of Hodgkin's disease and Wilms' tumor the attributes most affected were emotion and pain. In general, there was considerable agreement between the assessments provided independently by parents and physicians. This study demonstrates the feasibility of conducting such measurements in developing countries, and reveals similarities in health status and health-related quality of life to comparable populations in more privileged societies.

Child↗
PubMed2001

[Suprahepatic vein catheterization in 4 cases of severe septic shock].

Splanchnic hypoperfusion, with pathogenic implications for multiple organ failure, can occur during septic shock. We report four patients with septic shock in whom regional hepatosplenic splanchnic perfusion was monitored through suprahepatic vein catheterization and gastric tonometry. Suprahepatic lactate and oxygen saturation showed splanchnic hypoperfusion in all patients. These parameters improved only in the patient that survived. Gastric tonometry was more inconsistent. We conclude that suprahepatic vein catheterization could have a role in the management of septic shock.

Adult↗
PubMed2001

[Value of endonasal endoscopic surgery in the treatment of sphenoid cerebrospinal rhinorrheas. 15 cases].

UNLABELLED: Surgical management of cerebrospinal fluid leaks (CSFL) has improved these few past years with the development of paranasal sinus surgery under optical guidance. CSFL localized in the sphenoid sinus represent only 5 to 15% of all CSFL. The authors have analyzed a serie of 15 patients having undergone surgery from 1992 to 1999 for CSFL: 10 cases followed pituitary gland surgery realized through sublabial-transsphenoidal approach, 2 cases followed head trauma, 1 case followed a secondary neurosurgical procedure following recurrence of a rathke's cleft cyst, 1 case followed medical treatment of a bulky pituitary gland adenoma and 1 case was associated to an empty sella syndrome. The surgical procedure has relied on sphenoid sinus approach through the sphenoethmoidal recess (SER) (n = 8), transethmoidal approach (TE) (n = 2) or transseptal approach (TS) (n = 7) followed by a filling of the defect by a graft of fat with biological glue (n = 17). Sometimes it was associated to a cartilagenous graft (n = 7) when there was a bone defect. The average period of hospitalisation was 5.2 days (4-21), mean follow-up was 2.9 years (6 months-7 years). RESULTS: The success rate was 80% (3 failures were observed), 2 patients underwent secondary procedures by TS approach with success. Our results combined with the literature data led us to propose an alternative surgical strategy adapted to each case. Endonasal surgery under optic guidance compared to the transrhinoseptal approach represents an attractive alternative with less undesirable iatrogenic consequences.

Adipose Tissue↗
PubMed2001

Tropical spastic paraparesis.

Human T-cell lymphotropic virus type I (HTLV-I) is the cause of endemic tropical spastic paraparesis (TSP) or HTLV-I-associated myelopathy (HAM). Because TSP/HAM is not a fatal disease, the neuropathology of this disease, albeit relatively well understood, is based on the examination of just a few incidental cases. We summarise our experience with the neuropathology of tropical spastic paraparesis/HTLV-I associated myelopathy (TSP/HAM). We studied three cases of TSP/HAM from different parts of the world. We demonstrated peculiar lamellated structures, called "multilamellar bodies" (MLB). It is tempting to suggest that MLB may represent specific ultrastructural markers of TSP/HAM. The pathology of the anteriorand posterior horns was similar and comprised axonal degeneration, accompanied by extensive astrocytic gliosis. Lymphocytic infiltration, particularly observed as "cuffs" around blood vessels, was scattered among other cellular elements. Ultrastructurally, myelin sheaths were relatively well preserved, and some demyelinated but not remyelinated fibres were observed. Moreover, axons with abnormal accumulations of neurofilaments, suggestive of axonal degeneration, were detected. Several axons contained Hirano bodies. In many samples glial processes replaced most of the remaining neuropil.

Ganglia, Spinal↗
PubMed2000

Blood glutathione synthesis rates in healthy adults receiving a sulfur amino acid-free diet.

The availability of cysteine is thought to be the rate limiting factor for synthesis of the tripeptide glutathione (GSH), based on studies in rodents. GSH status is compromised in various disease states and by certain medications leading to increased morbidity and poor survival. To determine the possible importance of dietary cyst(e)ine availability for whole blood glutathione synthesis in humans, we developed a convenient mass spectrometric method for measurement of the isotopic enrichment of intact GSH and then applied it in a controlled metabolic study. Seven healthy male subjects received during two separate 10-day periods an L-amino acid based diet supplying an adequate amino acid intake or a sulfur amino acid (SAA) (methionine and cysteine) free mixture (SAA-free). On day 10, L-[1-(13)C]cysteine was given as a primed, constant i.v. infusion (3 micromol x kg(-1) x h(-1)) for 6 h, and incorporation of label into whole blood GSH determined by GC/MS selected ion monitoring. The fractional synthesis rate (mean +/- SD; day(-1)) of whole blood GSH was 0.65 +/- 0.13 for the adequate diet and 0.49 +/- 0.13 for the SAA-free diet (P < 0.01). Whole blood GSH was 1,142 +/- 243 and 1,216 +/- 162 microM for the adequate and SAA-free periods (P > 0.05), and the absolute rate of GSH synthesis was 747 +/- 216 and 579 +/- 135 micromol x liter(-1) x day(-1), respectively (P < 0.05). Thus, a restricted dietary supply of SAA slows the rate of whole blood GSH synthesis and diminishes turnover, with maintenance of the GSH concentration in healthy subjects.

Adult↗
PubMed2000

Effects of PAD on conduction of action potentials within segmental and ascending branches of single muscle afferents in the cat spinal cord.

In anesthetized and paralyzed cats under artificial respiration, we examined the extent to which primary afferent depolarization (PAD) might affect invasion of action potentials in intraspinal axonal and/or terminal branches of single muscle afferents. To this end, one stimulating micropipette was placed at the L6 spinal level within the intermediate or motor nucleus, and another one at the L3 level, in or close to Clarke's column. Antidromically conducted responses produced in single muscle afferents by stimulation at these two spinal levels were recorded from fine lateral gastrocnemius nerve filaments. In all fibers examined, stimulation of one branch, with strengths producing action potentials, increased the intraspinal threshold of the other branch when applied at short conditioning testing stimulus intervals (<1.5-2.0 ms), because of the refractoriness produced by the action potentials invading the tested branch. Similar increases in the intraspinal threshold were found in branches showing tonic PAD and also during the PAD evoked by stimulation of group I afferent fibers in muscle nerves. It is concluded that during tonic or evoked PAD, axonal branches in the dorsal columns and myelinated terminals of muscle afferents ending deep in the L6 and L3 segmental levels continue to be invaded by action potentials. These findings strengthen the view that presynaptic inhibition of muscle afferents produced by activation of GABAergic mechanisms is more likely to result from changes in the synaptic effectiveness of the afferent terminals than from conduction failure because of PAD.

Action Potentials↗
PubMed2000

Arginine, citrulline, and nitric oxide metabolism in end-stage renal disease patients.

The kidneys are thought to be a major site of net de novo arginine synthesis, but the quantitative status of arginine metabolism and its substrate precursor relationship to nitric oxide (NO) synthesis in end stage renal disease (ESRD) patients have not been characterized. We have investigated kinetic aspects of whole body arginine metabolism in six patients with ESRD. They received two pre- and two post-hemodialysis intravenous tracer infusion studies with L-[guanidino-(15)N(2)]arginine and L-[(13)C]leucine during the first study, and L-[5-(13)C]arginine and L-[5-(13)C-ureido,5,5, (2)H(2)]citrulline during the second study. Arginine homeostasis in ESRD patients was found to be associated with a lower rate of arginine oxidation, and despite the decrease in renal function, the rate of de novo arginine synthesis appeared to be preserved. Plasma citrulline concentrations and flux were also elevated in these subjects compared with healthy adults. The rate of whole body NO synthesis was increased in the ESRD patients, but apparently not different pre- and post-hemodialysis therapy. The anatomic site(s) responsible for the maintenance of net de novo arginine synthesis and for the elevated NO synthesis and its pathophysiological importance in ESRD remain to be established.

Adult↗
PubMed2000

[Client categorization: a tool to assess nursing workload].

BACKGROUND: Client categorization is a management tool that allows an objective and structured assessment of the care demands imposed by patients and nursing workloads. AIM: To characterize the need for direct nursing care of patients admitted to a university hospital. PATIENTS AND METHODS: During two months, all patients admitted to intensive, intermediate care units and general services were categorized, their need for nursing care and the time invested by nurses in their care was registered. All patients were classified as maximal, high, median or low risk and as independent, totally or partially dependent on nursing care. Considering four degrees of risk and three degrees of dependency, 12 categories of patients were defined. RESULTS: Patients admitted to intensive care units were of maximal risk and totally dependent and required 1 nurse per 2.2 patients. Those admitted in intermediate care units required 1 nurse per 3.8 patients and those in general services, 1 nurse per 11.5 patients. CONCLUSIONS: Client categorization is a reproducible method that determines a standard measuring unit to define nursing needs. This allows the comparison of workloads between different services within a hospital or between hospitals.

Humans↗
PubMed2000

[Parathyroid carcinoma: diagnosis and treatment].

Pre operative and per-operative suspicion, and recognition of parathyroid carcinoma are essential in the effective approach and the prognosis of this type of tumor. On the basis of our experience over 20 years, helped by the literature we review our 179 cases of primary hyperparathyroidism out of which 5 were malignant tumors and the 174 others were benign (adenomas and hyperplasias). We conclude that patients with primary hyperparathyroidism, reflected by high levels of serum calcium (75%) and elevated levels of parathormone (100%) are suspect of carrying a parathyroid malignancy particularly when these levels are profoundly abnormal. Furthermore, a severe clinical presentation featuring, palpable cervical mass, renal symptoms in 30% to 60% of all, bone disease in 90%, is suspect of malignancy. The operative findings such as important size of tumour, local seeding, local invasion are also significant features of malignancy. All this data gathered by comparing carcinomas to adenomas suggest and confirm what many reviews on the subject have reported, early recognition of the parathyroid carcinoma is of primal importance, because aggressive initial surgical management should be applied, as total extirpation of the malignancy is the only treatment allowing maximal survival rates.

Aged↗
PubMed2000

[Predictive malignancy factors in thyroid nodular disease].

Nodular thyroid pathology is frequent and remains a controversial issue when it comes to establishing an ideal endocrine surgical strategy. We studied clinical and complementary data predictive of malignancy using a large retrospective analysis of 366 cases operated for nodular pathology of the thyroid gland between January 1995 and December 1997 in our Head and Neck Surgery Unit of the Pasteur Hospital in Nice, France. The incidence of malignancy was 12.8% with the usual histologic findings (83% of well-differentiated tumors: 70% papillary, 13% vesicular, 9% medullar, 6% oncocytic and 2% anaplastic). Statistical analysis did not conclude on the predictive value of several items in terms of their relationship to high risk of malignancy (p > 0.05): size of nodules, signs of local compression, biological findings, presence of calcifications, mixed ultrasound aspect, no hypoechogenic halo, scintigraphic aspect. This retrospective work did however identify items predictive of malignancy when appearing in patients with nodular thyroid disease: male sex (odds ratio 2.4; 95%CI [1.17-4.88]; p=0.13), age (less than 40 yr or more than 70yr) (p=0.003), hard nodule consistency (odds ratio 7.40; 95%CI [3.99-13.52], p<0.001), invasion of lymphatic nodes noted prior to surgery (p=0.031), hyperechogenicity on ultrasound exam (p=0.013). We were able to confirm the highly negative predictive value (92%) of fine needle aspiration, emphasizing its value in endocrine thyroid nodular disease diagnosis.

Adolescent↗
PubMed2000

[Use of amphotericin B in lipid emulsions: does it prevent its toxicity in critically ill patients?].

BACKGROUND: Amphotericin B is efficacious for the treatment of systemic candidiasis, however it has potentially serious toxic effects. Administration as lipid emulsions has been advocated to decrease its toxicity. AIM: To compare the safety and tolerance of amphotericin B administered as lipid emulsion or dissolved in dextrose in water. PATIENTS AND METHODS: Forty five patients with confirmed or highly suspected systemic candidiasis were studied. Between January 1996 and June 1997 amphotericin B was administered in dextrose in water to 17 patients (group 1). Between July 1997 and December 1998, the drug was delivered in lipid emulsions (Intralipid, group 2). Clinical and laboratory parameters (serum creatinine, urea nitrogen and potassium), were assessed daily. RESULTS: Both treatment groups were clinically comparable and had the same survival. Accumulative amphotericin B dose administered was 343.2 +/- 197 and 414.6 +/- 518 mg respectively. Hypokalemia was more frequent in group 2 (52 and 25% respectively, p < 0.05). There were no differences in the outcome of renal function or other adverse reactions. CONCLUSIONS: Administration of amphotericin B as lipid emulsions did not reduce its toxicity in critical patients (Rev Méd Chile 2000; 128: 1101-07).

APACHE↗
PubMed1999

Gut mucosal atrophy after a short enteral fasting period in critically ill patients.

PURPOSE: The purpose of this study was to evaluate the presence of gut mucosal atrophy and changes in mucosal permeability in critically ill patients after a short fasting period. MATERIALS AND METHODS: Fifteen critically ill patients underwent a period of enteral fasting of at least 4 days (mean 7.8 days). We took the following measurements the day before initiating enteral nutrition: indirect calorimetry, serum albumin, prealbumin, and lymphocyte count. We also performed a duodenal endoscopic biopsy with histopathological and mucosal morphometric analysis including villus height and crypt depth. The lactulose-mannitol test was performed to assess gut permeability. A total of 28 healthy volunteers served as controls for duodenal biopsy or lactulose-mannitol test. Clinical data, such as length of fasting, severity score, and previous parenteral nutritional support, were recorded. RESULTS: We found gut mucosal atrophy, expressed as a decrease in villus height and crypt depth, in patients compared with controls. The patients also exhibited an abnormal lactulose-mannitol test. Morphometric changes did not correlate with permeability. Further, we found no correlation between the results of the lactulose-mannitol test and of mucosal morphometry with clinical data. CONCLUSIONS: We found that a short period of enteral fasting was associated with significant duodenal mucosal atrophy and abnormal gut permeability in critically ill patients.

Adult↗