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Biomedical subjects

J Gonzalez

Publications and source records attributed to J Gonzalez.

At least 55 records · Page 3Linked to original sources
PubMed2000

Successful treatment of active ankylosing spondylitis with the anti-tumor necrosis factor alpha monoclonal antibody infliximab.

OBJECTIVE: Tumor necrosis factor alpha (TNFalpha) has been detected in sacroiliac joint biopsy specimens from patients with spondylarthropathy. The present open pilot study was undertaken to test the efficacy of the anti-TNFalpha monoclonal antibody infliximab in the treatment of active ankylosing spondylitis (AS). METHODS: Eleven patients with AS of short duration (median 5 years, range 0.5-13 years) that had been active for at least 3 months (range 3-72 months) were treated with 3 infusions of infliximab (at weeks 0, 2, and 6), in a dosage of 5 mg/kg. Ten of the 11 patients had elevated C-reactive protein (CRP) levels (>6 mg/liter) before treatment; these elevations were known to have had persisted > 1 year in at least 3 patients. The Bath AS Disease Activity Index (BASDAI), the Bath AS Functional Index (BASFI), pain as measured on a visual analog scale, and the Bath AS Metrology Index (BASMI) were assessed. Quality of life was assessed using the Short Form 36 instrument. Laboratory markers of disease activity, including interleukin-6 (IL-6) levels, were determined. Dynamic magnetic resonance imaging (MRI) of the spine was performed in 5 patients. RESULTS: One patient withdrew from the study due to the occurrence of urticarial xanthoma 8 days after the first infusion. At study enrollment, 3 of 5 patients had evidence of spinal inflammation (spondylitis and spondylodiscitis) as detected by MRI; followup MRI 2-6 weeks after the third infusion revealed improvement in 2. Improvement of > or = 50% in activity, function, and pain scores was documented in 9 of 10 patients; the median improvement in the BASDAI after 4 weeks was 70% (range 41-94%). This clear-cut benefit lasted for 6 weeks after the third infusion in 8 of 10 patients. The median CRP level decreased from 15.5 mg/liter (range <6-90.8) to normal, and the median IL-6 level from 12.4 mg/liter (range 0-28.4) to normal (<5). There was improvement in all 9 SF-36 concepts; the improvement was significant for 6 concepts. CONCLUSION: These data suggest that anti-TNFalpha therapy is very effective for several weeks in AS. Whether this therapy, in addition to its antiinflammatory effect, prevents ankylosis remains to be determined.

Adult↗
PubMed2000

Scleromyxedema with dermato-neuro syndrome.

Scleromyxedema is a rare connective tissue disease of unknown cause characterized by a generalized papular eruption, dermal fibroblast proliferation, and monoclonal paraproteinemia. A paroxysmal triad consisting of high fever, seizures, and coma with a flu-like prodrome can rarely occur in patients with scleromyxedema and is termed "dermato-neuro syndrome." We describe a 41-year-old patient with scleromyxedema in whom the dermato-neuro syndrome developed.

Adult↗
PubMed2000

Bypass to the genicular arteries for revascularisation of the lower limb.

OBJECTIVE: To describe an initial experience with infrainguinal bypass grafts inserted distally in a genicular artery. DESIGN: Retrospective case series study. SUBJECTS AND METHODS: Eleven patients with Grade III chronic limb ischaemia in whom arteriography showed femoropopliteal occlusive disease and at least one genicular branch suitable for receiving a bypass. Bypass grafts were done to the descending genicular artery (n=4) or the medial sural artery (n=6) using segments of autologous veins; one bypass was not completed. RESULTS: Primary graft patency and foot salvage rates were 73% at 1 month and 24 months of follow-up. Patient survival rate was 100% and 90%, respectively. Major amputation was required in two of three patients following early graft failure. Of the eight patients who had a patent graft, the Doppler ankle-brachial systolic pressure index showed no change in one patient, an increase of 0.13-0.66 in six patients, and was not measured in one patient. The former patient underwent a below-knee amputation whereas the other seven patients showed complete healing of their skin ulcers and sites of minor amputation. CONCLUSION: The genicular bypass is a useful alternative that may extend the limits of infrainguinal arterial reconstruction with autologous tissue and the potential for long-term patient benefit.

Aged↗
PubMed2000

Extracorporeal photochemotherapy alone or with adjuvant therapy in the treatment of cutaneous T-cell lymphoma: a 9-year retrospective study at a single institution.

BACKGROUND: Extracorporeal photochemotherapy (ECP; photopheresis) is a treatment option for cutaneous T-cell lymphoma (CTCL). OBJECTIVE: This study describes the outcomes obtained with ECP alone or with adjuvant therapy in treating CTCL. METHODS: A 9-year retrospective study was performed at a single institution. RESULTS: Among 69 patients, 37 were treated with 6 months or more of ECP alone over an average of 36.9 months. Of these patients, 68% (25/37) had stage T2, 5% (2/37) had stage T3, and 27% (10/37) had stage T4 CTCL. Complete response (no skin or systemic disease for 1 month or more) and partial response (50%-99% skin improvement for 1 month or more) were achieved by 14% (5/37) and 41% (15/37) of patients, respectively, giving an overall response rate of 54% (20/37). In recalcitrant patients, adjuvant therapy significantly increased the response rate from 31% (4/13) to 69% (9/13) (P = 0.004). ECP was well tolerated in the entire patient population. CONCLUSION: Response rates in this study compared favorably with those in previous studies, underscoring the potential value of ECP in treating CTCL. To our knowledge, this investigation included the largest group of CTCL patients ever treated with ECP at a single institution.

Adult↗
PubMed2000

Evaluation of antimicrobial treatment in mechanically ventilated patients with severe chronic obstructive pulmonary disease exacerbations.

OBJECTIVE: To study microbial and susceptibility patterns and antimicrobial treatment responses in patients with severe, acute exacerbations of chronic obstructive pulmonary disease requiring mechanical ventilation. DESIGN: Microbial investigation using tracheobronchial aspirates, bronchoscopy with a protected specimen brush, and bronchoalveolar lavage, as well as paired serologies. Evaluation of antimicrobial treatment by results of the initial investigation, susceptibility testing, and a repeated microbial investigation (tracheobronchial aspirates, bronchoscopy with a protected specimen brush, and bronchoalveolar lavage) after 72 hrs. SETTING: A respiratory intensive care unit of a 1,000-bed teaching hospital. PATIENTS: Fifty severely exacerbated and mechanically ventilated patients with chronic obstructive pulmonary disease. INTERVENTIONS: Initial empirical antimicrobial treatment according to clinical judgment. MEASUREMENTS AND MAIN RESULTS: Overall, 36 of 50 patients (72%) had evidence of a microbial origin. Community-acquired endogenous pathogens were present in 70% of patients, and Gram-negative enteric bacilli and Pseudomonas/Stenotrophomonas species were present in 30%. All five isolates of Streptococcus pneumoniae were resistant to penicillin (three intermediately and two highly), and three were resistant to multiple antibiotics. Pseudomonas species revealed multiresistance in four of nine isolates (44%), and Stenotrophomonas maltophilia revealed multiresistance in one of two isolates. Antimicrobial treatment was modified according to diagnostic results in 11 of 31 patients (36%) with potentially pathogenic microorganisms. In patients who underwent a repeat investigation after 72 hrs, 24% of the initially present and potentially pathogenic microorganisms persisted. Inappropriate initial antimicrobial therapy was associated significantly with bacterial persistence (p < .002). CONCLUSIONS: Considering the diversity of microbial pathogens and the resistance rates especially to S. pneumoniae in this patient population, antimicrobial treatment should be based on the constant study of local microbial and susceptibility patterns along with routine microbial investigation of the individual patient.

Aged↗
PubMed2000

Finite-size scaling and conformal anomaly of the ising model in curved space

We study the finite-size scaling of the free energy of the Ising model on lattices with the topology of the tetrahedron and the octahedron. Our construction allows us to perform changes in the length scale of the model without altering the distribution of the curvature in the space. We show that the subleading contribution to the free energy follows a logarithmic dependence, in agreement with the conformal field theory prediction. The conformal anomaly is given by the sum of the contributions computed at each of the conical singularities of the space, except when perfect order of the spins is precluded by frustration in the model.

Journal Article↗
PubMed2000

Short-term prediction of chaotic time series by using RBF network with regression weights.

We propose a framework for constructing and training a radial basis function (RBF) neural network. The structure of the gaussian functions is modified using a pseudo-gaussian function (PG) in which two scaling parameters sigma are introduced, which eliminates the symmetry restriction and provides the neurons in the hidden layer with greater flexibility with respect to function approximation. We propose a modified PG-BF (pseudo-gaussian basis function) network in which the regression weights are used to replace the constant weights in the output layer. For this purpose, a sequential learning algorithm is presented to adapt the structure of the network, in which it is possible to create a new hidden unit and also to detect and remove inactive units. A salient feature of the network systems is that the method used for calculating the overall output is the weighted average of the output associated with each receptive field. The superior performance of the proposed PG-BF system over the standard RBF are illustrated using the problem of short-term prediction of chaotic time series.

Algorithms↗
PubMed2000

H pylori infection. Review of the guideline for diagnosis and treatment.

Helicobacter pylori infection is prevalent among persons over age 60, is strongly associated with peptic and duodenal ulcer, and is caused by a microbe classified as a carcinogen. These factors combine to make the primary care physician key to proper diagnosis and treatment of H pylori infection. In 1998, the American College of Gastroenterology published an evidence-based guideline for the management of this infection. The guideline produced several fundamental recommendations that help clarify the management process: asymptomatic persons should not undergo testing, but testing should be performed on certain persons, testing should only be done if the intention is to treat; the choice of test is governed by the need for endoscopy; and several triple-therapy regimens are effective for eradication.

Aged↗
PubMed1999

Uniparental isodisomy resulting from 46,XX,i(1p),i(1q) in a woman with short stature, ptosis, micro/retrognathia, myopathy, deafness, and sterility.

We report on a 43-year-old woman who was referred for evaluation because of minor facial anomalies, myopathy, sterility, short stature, hearing loss, downward slant of palpebral fissures, bilateral ptosis, severe micro/retrognathia, high arched palate, and scoliosis. Cytogenetic analyses utilizing GTG/CBG bandings showed presence of one i(1p) and one i(1q) without normal chromosome 1 homologues. Fluorescence in situ hybridization analysis showed hybridization to only two chromosomes, consistent with the G-banded interpretation of i(1p) and i(1q). To the best of our knowledge, this is the first case of isochromosomes 1p and 1q replacing the two normal chromosome 1s. Molecular investigations using markers for chromosome 1 showed inheritance of only one set of paternal alleles and absence of any maternal alleles in the patient. The adverse phenotype of the patient may be due to one or more recessive mutations, genomic imprinting, or a combination of both.

Abnormalities, Multiple↗
PubMed1999

Proteasome-dependent cyst formation and stage-specific ubiquitin mRNA accumulation in Entamoeba invadens.

Proteases play an important role in the pathogenic mechanisms and differentiation events of protozoan parasites; the proteasome/ubiquitin system is essential for maintaining the differentiation state of many cell types. A single input of the specific inhibitor of proteasomes, lactacystin, prevented encystation of the protozoan parasite Entameoba invadens, whereas a cysteine protease inhibitor, E64, only delayed encystation. The ameba target of lactacystin was purified and it displayed the features typical of eukaryotic 20S proteasome complexes. In addition, transcripts encoding ubiquitin were detectable in trophozoites stage cells, disappeared immediately following transfer of amoebae to encystation induction medium, and reappeared at the same time during encystation as other encystation-specific transcripts. These results demonstrate that proteasome function is required during the conversion of the disease-causing trophozoite into the infectious cyst stage of Entamoeba parasites, and that ubiquitin transcript levels undergo an unusual decrease during the early stages of this differentiation process.

Acetylcysteine↗
PubMed1999

Ondansetron and droperidol in the prevention of postoperative nausea and vomiting.

We have performed a prospective, randomized, double-blind clinical study to assess the efficacy of ondansetron, droperidol, or both, in preventing postoperative emesis. We studied 242 patients undergoing biliary or gynaecological surgery under general anaesthesia. Shortly before induction of anaesthesia, patients received: saline i.v. (group I, n = 62); droperidol 2.5 mg i.v. (group 2, n = 60); ondansetron 4 mg i.v. (group 3, n = 57); or droperidol 2.5 mg with ondansetron 4 mg i.v. (group 4, n = 63). Nausea occurred in 45%, 37%, 32% and 29% (P = 0.234) and vomiting in 23%, 17%, 9% and 5% (P = 0.016) of patients in groups 1, 2, 3 and 4, respectively, during the first 24 h. Groups 2 and 4 had greater sedation scores than group 1 during the first 3 h (P < 0.01). We conclude that both droperidol and ondansetron showed a significant antiemetic effect, ondansetron was not significantly better than droperidol, and the combination of droperidol and ondansetron was better than droperidol but no better than ondansetron alone.

Adolescent↗
PubMed1999

What if your patient prefers an alternative pain control method? Self-hypnosis in the control of pain.

Despite the availability of specialized treatments for chronic pain, including biofeedback training, relaxation training, and hypnotic treatment, most physicians rely on the traditional approaches of surgery or pharmacotherapy. The patient in this case study had severe and chronic pain but found little relief from pain medications that also caused side effects. She then took the initiative to learn and practice self-hypnosis with good results. Her physician in the resident's internal medicine clinic supported her endeavor and encouraged her to continue self-hypnosis. This patient's success shows that self-hypnosis can be a safe and beneficial approach to control or diminish the pain from chronic pain syndrome and can become a useful part of a physician's therapeutic armamentarium.

Accidents, Traffic↗
PubMed1999

A chest wall restrictor to study effects on pulmonary function and exercise. 2. The energetics of restrictive breathing.

Chest wall restriction, whether caused by disease or mechanical constraints such as protective outerwear, can cause decrements in pulmonary function and exercise capacity. However, the study of the oxygen cost associated with mechanical chest restriction has so far been purely qualitative. The previous paper in this series described a device to impose external chest wall restriction, its effects on forced spirometric volumes, and its test-retest reliability. The purpose of this experiment was to measure the oxygen cost associated with varied levels of external chest wall restriction. Oxygen uptake and electromyogram (EMG) of the external intercostals were recorded during chest restriction in 10 healthy males. Subjects rested for 9 min before undergoing volitional isocapnic hyperpnea for 6 min. Subjects breathed at minute ventilations (V.I) of 30, 60, and 90 liters/min with chest wall loads of 0, 25, 50 and 75 mm Hg applied. Frequency of breathing was set at 15, 30, and 45 breaths per minute with a constant tidal volume (VT) of 2 liters. Oxygen uptake was measured continuously at rest and throughout the hyperventilation bouts, while controlling V.I and VT. Integrated EMG (IEMG) from the 3rd intercostal space was recorded during each minute of rest and hyperventilation. Two-way ANOVA with repeated measures revealed that chest wall loading and hyperpnea significantly increased V.O2 values (p < 0.01). External intercostal IEMG levels were significantly increased (p < 0.05) at higher restrictive load (50 and 75 mm Hg) and at the highest minute ventilation (90 liters/min). These data suggest that there is a significant and quantifiable increase in the oxygen cost associated with external chest wall restriction which is directly related to the level of chest wall restriction.

Adult↗
PubMed1999

Hyponatremia-associated rhabdomyolysis.

BACKGROUND: Hyponatremia is the most frequent electrolyte disorder. However, hyponatremia rarely results from excessive water intake, unless the kidney is unable to excrete free water, such as in patients on thiazide diuretics; in addition, hyponatremia is an uncommon cause of rhabdomyolysis. METHODS: We present a 51-year-old hypertensive woman on chronic hydrochlorothiazide therapy who developed acute water intoxication and severe myalgias. RESULTS: The patient developed acute hypotonic hyponatremia and subsequent rhabdomyolysis. We discuss the mechanisms responsible for the development of hyponatremia and its association with rhabdomyolysis. CONCLUSION: Muscle enzymes should be monitored in patients with acute hyponatremia who develop muscle pain, and hyponatremia-induced rhabdomyolysis must be considered in patients with myalgias receiving thiazide diuretics.

Benzothiadiazines↗
PubMed1999

Airway inflammation and bronchial microbial patterns in patients with stable chronic obstructive pulmonary disease.

The effect of bacterial colonization of the bronchi on the progress of airflow limitation is not well known. Therefore, the pattern of airway inflammation in smokers and patients with stable chronic obstructive pulmonary disease (COPD) and its relation to bronchial microbial colonization was assessed. Eight nonsmoking and 18 smoking controls as well as 52 patients with COPD (28 mild, 11 moderate and 13 severe) were studied. All subjects were investigated by means of flexible bronchoscopy including protected specimen brush and bronchoalveolar lavage (BAL) sampling. Differential cell counts, cytokine (interleukin (IL)-1beta, IL-6, IL-8, IL-10 and tumour necrosis factor-alpha(TNF-alpha) concentrations and microbial patterns were determined in BAL fluid. Forced expiratory volume in one second (FEV1) % of the predicted value was inversely correlated with pack-yrs of cigarette smoking (r=-0.47, p<0.0001), the percentage of neutrophil (p=-0.56, p<0.0001) and IL-6 (p=-0.37, p=0.01) and IL-8 concentration (p=-0.43, p=0.004) in BAL fluid. Accordingly, pk-yrs of cigarette smoking (p=0.39, p=0.01) and IL-8 (p=0.69, p<0.0001) and TNFalpha (p=0.4, p<0.005) were positively correlated with the percentage of neutrophils in BAL fluid. Smoking controls and COPD patients were mainly colonized in the bronchial tree (33%) by community endogenous potentially pathogenic micro-organisms (PPMs). Colonization rates and patterns of PPMs were not affected by severity of airflow obstruction. The presence of PPMs was significantly associated with higher percentages of neutrophils (33.2+/-10.4% versus 10.1+/-3.5%, p=0.02) and TNF-alpha concentration (29.9+/-10.8 versus 6.3+/-2.1 pg x mL(-1), p=0.01) in BAL fluid. In conclusion, bronchial neutrophilia is a key inflammatory pattern in chronic obstructive pulmonary disease patients. Bronchial colonization with potentially pathogenic micro-organisms may represent an independent stimulus for additional airway inflammation.

Biopsy↗
PubMed1999

Gains of the relative genomic content of erbB-1 and erbB-2 in prostate carcinoma and their association with metastasis.

Prostate carcinoma (PC) is the second leading cause of cancer death in men in the western world. Although the role of oncogenes and growth factors in prostate carcinoma is still unclear, overexpression of the epidermal growth factor receptor (erbB-1) and the proto-oncogene erbB-2 have been reported in prostate tumors, and erbB-2 related to poor prognosis and distant metastasis. Recent allelotyping studies in prostate cancer have shown chromosomal gains in 7p and 17q, regions where erbB-1 and erbB-2 are localized respectively, although no direct evidence of an increased gene copy number of either erbB-1 or erbB-2 has been reported. To address this question, we analyzed 20 benign prostatic hyperplasia (BPH) samples and 36 samples of metastatic and non-metastatic PC by means of semiquantitative PCR. Thus, 64% (11/17) and 52% (10/19) of metastatic and non-metastatic tumors respectively showed gains of the relative genomic content of erbB-1 and an association of erbB-1 with prostate cancer but not with metastasis. Additionally, 41% (7/17) of metastatic samples showed gains of erbB-2 genomic content, suggesting an association of erbB-2 with metastasis and poor prognosis (p<0.005). No gains of erbB-1 or erbB-2 genomic content were detected in the BPH samples.

Aged↗