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J M Campos

Publications and source records attributed to J M Campos.

At least 19 recordsLinked to original sources
PubMed2002

Comparison of auditory evoked potentials and the A-line ARX Index for monitoring the hypnotic level during sevoflurane and propofol induction.

BACKGROUND: Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation of the appropriate signals of the AEP could be difficult to perform during the anesthesia procedure. This problem was addressed by defining an index which reflected the peak amplitudes and latencies of the AEP, developed to improve the clinical interpretation of the AEP. This index was defined as the A-line Arx Index (AAI). METHODS: The AEP and AAI were compared with the Modified Observers Assessment of Alertness and Sedation Scale (MOAAS) in 24 patients scheduled for cardiac surgery, anesthetized with propofol or sevoflurane. RESULTS: When comparing the AEP peak latencies and amplitudes and the AAI, measured at MOAAS level 5 and level 1, significant differences were achieved. (mean(SD) Nb latency: MOAAS 5 51.1 (7.3) ms vs. MOAAS 1: 68.6 (8.1) ms; AAI: MOAAS 5 74.9 (13.3) vs. MOAAS 1 20.7 (4.7)). Among the recorded parameters, the AAI was the best predictor of the awake/anesthetized states. CONCLUSION: We conclude that both the AAI values and the AEP peak latencies and amplitudes correlated well with the MOAAS levels 5 (awake) and 1 (anesthetized).

Anesthesia↗
PubMed2001

Optochin resistance in Streptococcus pneumoniae: mechanism, significance, and clinical implications.

Traditionally, Streptococcus pneumoniae is identified in the laboratory by demonstrating susceptibility to optochin. Between 1992 and 1998, 4 pneumococcal isolates exhibiting optochin resistance were recovered from patients at Children's National Medical Center. Three of the 4 isolates consisted of mixed populations of optochin-resistant and -susceptible organisms. Both subpopulations had identical antibiograms, serotypes, and restriction fragment profiles. The other isolate was uniformly resistant to optochin. Resistant strains had MICs of optochin 4-30-fold higher than susceptible strains, belonged to different serotypes, and had dissimilar restriction fragment profiles, indicating clonal unrelatedness. Resistance arose from single point mutations in either the a-subunit (W206S) or the c-subunit (G20S, M23I, and A49T) of H(+)-ATPase. There is speculation of a possible association between exposure to antimalarial drugs and evolution of optochin resistance. alpha-Hemolytic streptococci resistant to optochin, particularly invasive isolates, should be tested for bile solubility or with an S. pneumoniae DNA probe before identification as viridans streptococci.

Amino Acid Sequence↗
PubMed2001

A randomized, crossover comparison of standard-dose versus low-dose lenograstim in the prophylaxis of post-chemotherapy neutropenia.

The aim of this trial was to compare the severity of neutropenia, the frequency of hospital admission for fever or infection, and the use of antibiotics among patients treated with a standard dose of lenograstim (263 microg/day of Euprotin) and others treated with half of this dose (131.5 microg/day) and the cost-effectiveness of each of the two doses. In this single-center study, 44 patients with solid tumors, who were all receiving standard-dose chemotherapy regimens following previous neutropenia or were at high risk of neutropenia, were randomized to receive lenograstim at a dose of 263 microg or 131.5 microg daily in the first cycle and then crossed over to the alternate dose for the following cycle. Crossover to the alternate dose was repeated for patients who received more than two cycles. Lenograstim was administered from day +5 to day +14. The absolute neutrophil count (ANC) was assessed on days +5, +8, +12 and +15 of each cycle. Statistical analysis was performed using a general lineal model for repeated samples. In all, 120 cycles were administered, with a median of 3 cycles (range 1-6). Only 4 patients received only 1 cycle. No statistically significant difference (P=0.324) in ANC was observed between standard-dose (mean 5.3, 10.7, 8.3, 11.4 x 10(9)/l) and low-dose (5.0, 8.6, 5.4, 7.5 x 10(9)/l) treatment at days +5, +8, +12 and + 15. Neutropenia grade III-IV was more common in patients receiving the low than in those receiving the standard dose of lenograstim (20% vs 12%, respectively), but the difference did not reach statistical significance (P=0.1). The incidence of fever and frequency of hospital admission were not affected by the dose of lenograstim: 3 patients presented with fever with the standard dose (all of those were admitted to hospital) and 2 patients with the low dose (1 was admitted). ANC in both groups (standard and low doses) was independent of chemotherapy line (first versus second or more). Lenograstim at a dose of 131.5 microg/day is as effective as the standard dose in limiting the severity of neutropenia and in preventing episodes of fever and hospital admissions after chemotherapy for solid tumors. The lower dose of lenograstim is cost-effective in neutropenia prophylaxis. Starting its administration on day +5 reduces costs while maintaining efficacy.

Adjuvants, Immunologic↗
PubMed2000

Nosocomial enterococcal infections in children.

OBJECTIVES: To identify factors that are associated with an increased risk of nosocomial enterococcal infection in children. METHODS: A matched case-control study was conducted between January 1989 and July 1993 at the Children's National Medical Center, Washington DC. One control patient for each case was identified. Control patients did not have nosocomial enterococcal infections and were matched with cases on the basis of age and time of admission closest to the case within a three-month period. Data were collected from systematic review of patient medical records. One hundred and one study patients (cases) were matched with 101 control patients. A case was defined as a patient with enterococcal infection who met the Centers for Disease Control and Prevention criteria for nosocomial infection. Microbiology methods included isolation, identification, and antimicrobial susceptibility testing of enterococci from clinical specimens. RESULTS: Risk factors associated with nosocomial enterococcal infections were determined by multiple conditional logistic regression analyses of the cases and controls. Factors identified were placement of a central line, gastrointestinal tract pathology, and administration of multiple antimicrobial agents. The median duration of antimicrobial therapy prior to diagnosis of nosocomial enterococcal infection was approximately 1 week. CONCLUSION: The incidence of nosocomial enterococcal infections in children may be controlled by limiting the number of antimicrobial agents administered to hospitalized high risk patients. The importance of our findings is relevant in an era of increasing rates of antimicrobial resistance in nosocomial enterococcal infections.

Anti-Bacterial Agents↗
PubMed2000

Preoperative calcitonin levels are predictive of tumor size and postoperative calcitonin normalization in medullary thyroid carcinoma. Groupe d'Etudes des Tumeurs a Calcitonine (GETC).

Medullary thyroid carcinoma (MTC) is a calcitonin (CT)-secreting endocrine tumor. Although plasma CT level is a specific and sensitive marker of MTC, its preoperative usefulness in predicting tumor size and postoperative CT normalization has not been documented. From a nationwide database set up by the French CT Tumor Study Group, 226 MTC patients were selected according to the following criteria: preoperative CT level determination by an immunoradiometric assay (normal value, < 10 pg/mL) within the 6 months prior to surgery, total thyroidectomy and diagnosis of MTC ascertained by histological report including tumor size. Patients were 129 females and 97 males (female/male ratio, 1.3). One hundred and twelve patients (49.6%) had the sporadic variety of the disease, 74 (32.7%) had multiple endocrine neoplasia 2A, three (1.3%) had multiple endocrine neoplasia 2B, and 37 (16.4%) had familial MTC. Median age at diagnosis was 44.8 yr (range, 4.9-80.1 yr). Complete neck dissection was performed in 159 patients (70.4%). Postoperative CT normalization was ascertained by negative response of CT to pentagastrin stimulation (< 10 pg/mL) in 94 patients. Seventy-one patients were considered as not cured because of residual tumor tissue and/or elevated CT levels. Median tumor size was 11.0 mm (range, 0.2-80.0 mm), significantly larger in females (15.0 vs. 8.0 mm, P < 0.05), and in sporadic forms (15.0 vs. 7.0 mm, P < 0.05). Tumor size was significantly correlated (r2 = 0.52, P < 0.01) with preoperative CT levels, the relationship being more straight in familial (r2 = 0.71) than in sporadic (r2 = 0.36) forms. Furthermore, preoperative CT levels under 50 pg/mL appeared to be predictive of postoperative CT normalization (44 of 45 patients). However, higher CT levels did not mean absence of postoperative CT normalization (50 of 120 patients). We conclude that low preoperative CT levels are predictive of tumor size and postoperative CT normalization.

Adolescent↗
PubMed2000

[Comparison of an auditory evoked potentials index and a bispectral index versus clinical signs for determining the depth of anesthesia produced by propofol or sevoflurane].

OBJECTIVES: To evaluate an anesthetic depth index (ADI) obtained from auditory evoked potentials and a bispectral EEG index (BIS) in comparison with clinical assessment of anesthetic depth using the modified observer's assessment of awareness/sedation scale (MOAA/SS), for induction of anesthesia with propofol or sevoflurane as the only agent. PATIENTS AND METHODS: The ADI and BIS were recorded simultaneously in this prospective study and compared to the MOAA/SS during the anesthetic induction of 26 adults undergoing elective heart surgery. Assignment of patients to two groups was random. Group A (n = 13) patients were induced with propofol (target dose 5 micrograms.ml-1 in 5 min). Induction in group B (n = 13) was with sevoflurane (8% tidal volume). A scheme of awake-sleeping-awake-sleeping was followed. The means of the two indexes were compared (Mann-Whitney test) one minute before the patient slept (awake) and one minute later (sleeping), and the evolution of the indexes was compared during awake/sleep and sleep/awake phase changes and while the patients were in a stable sleep phase. The sensitivity and specificity of each index was analyzed in function of the MOAA/SS. We also analyzed the time elapsing from the moment the patient fell asleep (MOAA/SS 2) until the two indexes reached published reference values (ADI = 38, BIS = 60). RESULTS: After induction with propofol (group A) the ADI fell to 29.2 +/- 11.7 and the BIS fell to 63.5 +/- 13.4. After induction with sevoflurane (group B) the ADI fell to 33.8 +/- 14.9 and the BIS to 66.8 +/- 15. The ADI value that best discriminated between arousal and sleeping (sensitivity 100%) was 38; the BIS value that best discriminated was 60. The responses to sound in decibels (dB) during "awake/sleeping" and "sleeping/awake" phases were, respectively, -3.8 dB and -4.5 dB for the ADI and -1.5 dB and -0.8 dB for the BIS. With the patient in stable sleep, response to the two indexes was at -0.79 dB. In group A, the ADI detected MOAA/SS 2 significantly earlier (ADI 13.1 +/- 30 s; BIS 56 +/- 36 s; p < 0.05). No patient reported remembering the study period. CONCLUSIONS: Monitoring anesthetic depth with the ADI or BIS was technically easy and effective for detecting whether patients were awake or sleeping. The ADI response was faster and identified awake/sleeping and sleeping/awake phase changes better than did the BIS.

Adult↗
PubMed1999

Vancomycin-resistant Enterococcus faecium colonization in children.

Nosocomial vancomycin-resistant Enterococcus (VRE) infections have been described in only small numbers of pediatric patients. In none of these studies were multivariate analyses performed to assess which factors were independent risk factors in these patients. In the present cohort study of patients admitted to our hematology/oncology unit, surveillance cultures revealed a colonization rate of 24% and all isolates were identified as Enterococcus faecium. Risk factors associated with colonization with VRE identified by multiple logistic regression analysis included young age and chemotherapy with antineoplastic agents, cefotaxime, vancomycin, and ceftazidime. A molecular epidemiological tool, pulsed-field gel electrophoresis, was used to determine the relatedness of the VRE isolates detected. DNA analysis by this method identified two major clusters of VRE isolates. Young children with gastrointestinal colonization with VRE, without evidence of clinical infection, can serve as a reservoir for the spread of VRE.

Anti-Bacterial Agents↗
PubMed1998

Prognostic factors for survival and for biochemical cure in medullary thyroid carcinoma: results in 899 patients. The GETC Study Group. Groupe d'étude des tumeurs à calcitonine.

BACKGROUND: Prognostic factors of sporadic or inherited medullary thyroid carcinoma (MTC) are still controversial and have been assessed in old and small series. A better knowledge of these factors would improve patient management. OBJECTIVE: To evaluate factors involved in the prognosis of MTC in a large series of cases, using uni- and multivariate analysis. DESIGN AND PATIENTS: Clinical, biological, surgical and epidemiological data on 899 MTC patients, diagnosed between 1952 and 1996, were collected by the French Calcitonin Tumors Study Group (GETC) with a standardized questionnaire, and processed in a national database. MEASUREMENTS: Survival and biochemical cure (i.e. normal basal post-operative serum calcitonin levels) were analysed with Kaplan and Meier and log-rank test statistical procedures. Data are presented as adjusted rather than observed survival, to consider only patients who died of MTC. Cox's forward-stepping proportional hazard model was used to analyse factors with a significant influence on survival by univariate analysis. RESULTS: Apart from the large proportion of familial forms (43%), the general characteristics of our population were similar to those in other studies: mean age at surgery = 43.4 years; sex ratio = 1 male/1.35 female; stage I = 20.8%; stage II = 21.2%; stage III = 46.5% and stage IV = 11.5%. 863 (96%) patients underwent surgery; 43% of operated patients were biochemically cured. Adjusted survival was 85.7 +/- 1.5% at 5 years and 78.4 +/- 2.1% at 10 years. Multivariate analysis showed that age and stage were independent predictive factors of survival. Gender, type of surgery, type of familial form were predictive only in univariate analysis. Biochemical cure predicts a survival rate of 97.7% at 10 years. Authentic recurrence, that is subsequent elevation of calcitonin (CT) after post-operative normalization, was found in 4.9%. In non-cured patients (57%), survival was still good: 80.2% (+/- 2.2%) and 70.3% (+/- 2.9%) at 5 and 10 years, respectively. Similarly, prediction of biochemical cure was solely dependent on stage. CONCLUSION: Survival of these medullary thyroid carcinoma patients appears better than expected even in non-cured patients. Considering the strong impact of stage, the necessity for pre-operative diagnosis of MTC is obvious.

Adult↗
PubMed1998

Sporadic medullary microcarcinoma of the thyroid: a retrospective analysis of eighty cases.

Clinical characteristics and prognosis of 80 patients (53 women and 27 men) with sporadic medullary thyroid carcinomas (MTC), less than 1 cm in size (micro-MTC), operated on between 1971 and 1996 are reported (73 total and 7 partial thyroidectomies). These patients, obtained from a national database of 899 patients with MTC, were compared with 357 cases of sporadic MTC greater than 1 cm and 149 subjects with familial MTC less than 1 cm (familial micro-MTC). Median age at surgery was 52.5 years, a distribution similar to larger sporadic MTC. Micro-MTC was identified due to elevated calcitonin (47.5%), clinically identified lymph node (10.0%), distant metastases (6.3%) or pathologic finding at surgery (36.2%). Diarrhea and/or flushing were observed in 6 patients including 4 with clinically identified lymph node. Among patients who had lymph node dissection at surgery (68.8%), lymph node involvement with tumor was observed in 30.9%, and was significantly more frequent in multifocal (7/11) than in unifocal micro-MTC (p < 0.03). All sporadic micro-MTC were unilateral. Survival rate was 93.9% +/- 4.4% (SE) at 10 years, greater than that observed in sporadic macro-MTC (p = 0.04). Normal postoperative basal calcitonin (CT) was obtained in 71.1% of micro-MTC patients versus 33.6% in sporadic macro-MTC (p < 0.01). Sporadic micro-MTC is much more frequent than expected, 15% of MTC in our series. Although specific survival rate and percentage of biological cure in micro-MTC are significantly better than for larger tumors, the frequency of lymph node involvement, however, justifies an aggressive surgical approach including total thyroidectomy and bilateral central lymph node dissection.

Adolescent↗
PubMed1997

A retrospective analysis of microbial contaminants in outdated random-donor platelets from multiple sites.

BACKGROUND: Platelet components contaminated with bacteria are an important source of transfusion-associated bacterial sepsis. Estimates of contamination rates vary widely (0-10%) and are highly controversial. The present study, designed with stringent testing regimens, retrospectively determined the prevalence of microbial contaminants in platelets from four collection regions. STUDY DESIGN AND METHODS: During a 9-month period, outdated platelet units were assayed by spreading aliquots from the unit, and from thioglycollate broth medium inoculated with part of the unit, onto 5-percent sheep blood agar media. Cultures were examined after 72-hour incubation at 37 degrees C, and, if bacterial growth was present, the assay processes were repeated with fresh inocula. Units were considered contaminated only if repeatedly positive. RESULTS: Four (0.08%) of 4995 units sampled were contaminated, two with Corynebacterium sp. and one each with Propionibacterium acnes and Aspergillus terreus. Contaminants were present at low, subclinical levels and were detected only after amplification in thioglycollate. The contaminated units were cultured 1, 2, 3, and 7 days after expiration. CONCLUSION: Contamination rates were low and did not vary by region. The identification of A. terreus suggests the role that transfusion may play in transmitting fungal infections should be reassessed. The persistent detection of contaminated platelet units supports the need for a test to detect clinically relevant levels of microbial contaminants in blood components.

Aspergillus↗
PubMed1997

Decreased susceptibility to imipenem among penicillin-resistant Streptococcus pneumoniae.

We assessed the antimicrobial susceptibilities of 59 penicillin-intermediate or penicillin-resistant pneumococci. All strains were susceptible to vancomycin and rifampicin. The frequency of strains with decreased susceptibility to cefotaxime, chloramphenicol, imipenem and meropenem was 15, 31, 47 and 49% respectively. The high percentage of penicillin-intermediate or penicillin-resistant Streptococcus pneumoniae with decreased susceptibility to third-generation cephalosporins, chloramphenicol and carbapenems limits the therapeutic options for the treatment of invasive pneumococcal infections and particularly of meningitis.

Anti-Bacterial Agents↗
PubMed1996

HIV antibody responses in children of HIV-infected mothers.

About 25% of the children of untreated HIV-infected mothers are later determined to be HIV-infected. At birth, all of the children of HIV-infected mothers have HIV-IgG antibody, which is transferred transplacentally from the mothers to their children, and infected children produce HIV-IgG antibody in response to their infection. Most infected children have detectable HIV-IgA by 3 months of age. We have studied HIV antibody responses in three groups of children of HIV-infected mothers at 9 to 12 months and 15 to 24 months of age. The groups were classified by Centers for Disease Control and Prevention (CDC) criteria and included: (I) HIV seroreverters (SR); (II) HIV-infected; Non- to mildly symptomatic (N+A); and (III) HIV-infected; Moderately to Severely Symptomatic (B+C). HIV-IgG antibody was detected in some SR children at low titer levels (10 to 20) through 11 months of age but not at 12 or later. For both the N+A and B+C groups, there were no significant changes in the mean HIV-IgG titers from 9-12 to 15-24 months of age. Also, no significant difference in titers were found between the two infected groups for both age groups. HIV-IgA antibody responses were more frequently positive at 15 to 24 months for all seven antigens studied for the N+A than the B+C patients; however, statistical significance was attained only for gp41 (p < or = 0.01). N+A children showed more responses to the viral antigens at 15-24 months than at 9-12 months. This increase in HIV-specific IgA among the N+A children may be important in restricting their HIV infections. Total IgG levels were significantly higher in the HIV-infected groups than in the SR (p < or = 0.0001), but no differences were detected between the N+A and B+C groups. Total IgA increased over time in the N+A patients from 9-12 to 15-24 months. A similar trend was apparent in the B+C group, but did not reach statistical significance. Both N+A and B+C patients at 15-24 months had significantly higher total IgA levels than did the SR at 9-12 months of age. The B+C group had significantly lower CD4 counts for both age groups than did the N+A or SR groups (p < or = 0.0001).

Antibody Specificity↗
PubMed1996

Pseudoatrophic macules: a variant of neurofibroma.

A 19-year-old man with neurofibromatosis type 1 showed a cutaneous plaque on the right scapular area with grayish coloration and atrophic appearance. Histopathologic examination demonstrated features of neurofibroma. Dermatologists should be aware of this uncommon clinical variant of neurofibroma in order to diagnose neurofibromatosis.

Adult↗
PubMed1995

Penicillin-resistant pneumococci from pediatric patients in the Washington, DC, area.

OBJECTIVE: To assess the prevalence and antimicrobial susceptibility of penicillin-resistant pneumococci (PRP) isolated from patients in a pediatric hospital. METHODS: All (108) isolates of Streptococcus pneumoniae recovered from usually sterile body sites between June 1, 1992, and May 31, 1993, were screened for susceptibility to penicillin by the E-test method. Minimum inhibitory concentrations of penicillin and other antibiotics were also determined by an agar dilution method for 10 PRP and 22 penicillin-susceptible strains. RESULTS: Fourteen isolates (12.9%) were PRP by the E-test; nine of these (8.3%) were intermediately resistant and five (4.6%) were highly resistant. All strains were sensitive to rifampin and vancomycin. Increased frequency of resistance to oral and parenteral cephalosporins and carbapenems was found among PRP; for most of these antibiotics, resistance exceeded 40% of the PRP. In addition, 20% of the PRP were resistant to macrolides and all penicillin-susceptible and PRP were resistant to a combination of trimethoprim and sulfamethoxazole. CONCLUSIONS: The decreased susceptibility to oral and parenteral cephalosporins, macrolides, a combination of trimethoprim and sulfamethoxazole, and carbapenems creates a significant problem in the treatment of pneumococcal infections in both ambulatory and hospitalized patients.

Adolescent↗
PubMed1995

Evaluation of E-Test for determination of antimicrobial MICs for Pseudomonas aeruginosa isolates from cystic fibrosis patients.

We determined the E-Test and National Committee for Clinical Laboratory Standards standardized agar dilution MICs of ceftazidime, ciprofloxacin, piperacillin, and tobramycin for Pseudomonas aeruginosa during tests of 100 rough and mucoid P. aeruginosa isolates from cystic fibrosis patients. The levels of agreement (+/- 1 log2 dilution) between quantitative E-Test and agar dilution MIC results were 80, 97, 73, and 89% for ceftazidime, ciprofloxacin, piperacillin, and tobramycin, respectively. Comparison of the results after converting the MIC data to qualitative categories (susceptible, intermediate, and resistant) yielded levels of agreement of 84, 96, 88, and 93% for the same agents, respectively. Of the 39 qualitative discrepancies, 36 were minor and 3 were very major. We conclude that use of the E-Test is easier and more practical than use of the agar dilution method for most laboratories and that the E-Test furnishes results which are at least as accurate as those obtained by the agar dilution method. However, the higher cost of the E-Test method would likely discourage most laboratories from selecting it over disk diffusion for routine antimicrobial susceptibility testing of P. aeruginosa isolates from cystic fibrosis patients.

Cystic Fibrosis↗