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Biomedical subjects

I Schwartz

Publications and source records attributed to I Schwartz.

At least 19 recordsLinked to original sources

Electrical twitch obtaining intramuscular stimulation (ETOIMS) for myofascial pain syndrome in a football player.

BACKGROUND: Flare up of acute lower back pain associated with myofascial pain syndrome (MPS) may require various forms of treatment including activity restriction and bracing. Electrical twitch obtaining intramuscular stimulation (ETOIMS) is a promising new treatment. It involves the use of a strong monopolar electromyographic needle electrode for electrical stimulation of deep motor end plate zones in multiple muscles in order to elicit twitches. CASE REPORT: An elite American football player with MPS symptoms failed to respond to standard treatments. He then received ETOIMS which completely alleviated the pain. After establishing pain control, the athlete continued with a further series of treatments to control symptoms of muscle tightness. CONCLUSIONS: ETOIMS has a promising role in pain alleviation, increasing and maintaining range of motion, and in providing satisfactory athletic performance during long term follow up.

Adult↗

In vivo and in vitro studies on Anaplasma phagocytophilum infection of the myeloid cells of a patient with chronic myelogenous leukaemia and human granulocytic ehrlichiosis.

AIMS: The occurrence of human granulocytic ehrlichiosis (HGE) in a patient with chronic myelogenous leukaemia (CML) provided an opportunity to study whether Anaplasma phagocytophilum, the aetiological agent of HGE, infects mature or immature cells, both in vivo and in vitro. METHODS: Diagnosis of HGE was confirmed by culture, polymerase chain reaction (PCR), detection of intragranulocytic inclusions, and serology. The infection rates of different myelogenous stages of granulocytic differentiation were determined by microscopy. Anaplasma phagocytophilum infection of the bone marrow was analysed by PCR, culture, and microscopy. In addition, the in vitro growth of A phagocytophilum in the patient's granulocytes and in HL-60 cells (a promyelocytic leukaemia cell line) was compared. RESULTS: Pretreatment blood smears showed that mature granulocytic cells had a higher infection rate with A phagocytophilum than did immature cells. In the original inoculation of the patient's cells into HL-60 cells to isolate A phagocytophilum, the bacterium grew faster in the patient's leukaemic cells than in HL-60 cells. Anaplasma phagocytophilum inclusions were rarely seen in bone marrow granulocytes and PCR was negative. In vitro, two A phagocytophilum isolates grew faster in the patient's granulocytes than in HL-60 cells. CONCLUSIONS: The superior growth in CML cells compared with HL-60 cells suggests that A phagocytophilum preferentially infects mature granulocytes. The higher infection rate of the patient's mature versus immature granulocytes before treatment and the minimal level of infection of the patient's bone marrow support this. It is possible that the primary site of infection in HGE is the peripheral mature granulocytic population.

Acute Disease↗

Effect of montelukast pretreatment on inducible nitric oxide synthase mRNA expression in the lungs of antigen-challenged allergic mice.

BACKGROUND: Growing evidence suggests that inducible nitric oxide synthase (iNOS) is the main source of the high output of exhaled nitric oxide (NO) in asthma. Treatment of asthmatic patients with glucocorticoids reduces high levels of exhaled NO mainly by inhibiting the transcription of iNOS. A similar reduction in exhaled NO was recently observed in patients treated with the leukotriene receptor antagonists, but the exact interaction between these drugs and iNOS remains obscure. OBJECTIVE: The purpose of this study was to evaluate the effect of a leukotriene receptor antagonist, montelukast, on the expression and activity of iNOS in a murine model of allergic asthma. METHODS: Twenty-four BALB/c mice were sensitized to OVA and were equally divided into 3 groups (Groups 1-3). Eight additional mice were sham sensitized and served as a negative control group (Group 4). Group 1 received montelukast 1 mg/kg/day in their drinking water, Group 2 received dexamethasone 1 mg/kg/day in their drinking water and Groups 3 and 4 received plain tap water. After 1 week, the animals were challenged by inhalation of OVA and, 3 h later, they were killed and their lung cells were isolated by enzymatic tissue digestion. NO generation was measured by a Griess assay, and iNOS mRNA was studied by RT-PCR. RESULTS: A significant increase in iNOS mRNA expression and in NO generation was evident after allergen challenge compared with the controls. Pretreatment with montelukast mildly decreased NO production without producing a concomitant significant decrease in iNOS mRNA expression. CONCLUSION: Unlike pretreatment with glucocorticoids, we failed to find compelling evidence for a major role for montelukast treatment in the modulation of iNOS mRNA in a murine model of acute asthma.

Acetates↗

ErbB-4 expression in limb soft-tissue sarcoma: correlation with the results of neoadjuvant chemotherapy.

ErbB-4 is a recently described growth factor receptor. Relatively little is known about its expression in human tumours. In this study, we assessed the possible role of erbB-4 as a tissue marker for soft-tissue sarcomas (STS) and its correlation with the response to chemotherapy. The histological specimen of 29 patients with STS of a limb who had received preoperative doxorubicin (ADR)-based chemotherapy were studied for the degree of necrosis and the expression of erbB-4 (by an avidin-biotin-peroxidase technique). ErbB-4 expression in the preoperative tissue samples was compared with the expression in the postchemotherapy resected tumour. The true objective response rate to preoperative chemotherapy was 34%. Wide resection of the tumour was done in 12 patients, marginal in 14, amputation in 2 and no surgery in 1. The tumour necrosis was above 90% in 9 patients, 60-90% in 12, and less than 60% in 7 patients. An increase in erbB-4 expression was more common in cases with no response to chemotherapy, while no change or a decrease in erbB-4 was more common in responsive tumours (P=0.004). No correlation could be found between the degree of necrosis or the chemotherapeutic regimen and the change in expression of erbB-4. The median disease-free survival (DFS) was longer for patients with a decrease or no change in expression of erbB-4 than for patients with increased expression. It is believed that postchemotherapy new expression or no downregulation of the erbB-4 molecule represents tumour aggressiveness and increased capability of growth and spread.

Adult↗

Laboratory diagnostic techniques for patients with early Lyme disease associated with erythema migrans: a comparison of different techniques.

Recently, a number of refinements in diagnostic modalities for detection of Borrelia burgdorferi infection have been developed. These include large-volume blood cultures, quantitative polymerase chain reaction (PCR) techniques, and 2-stage serologic testing. In the present study, we compared 6 diagnostic modalities in 47 adult patients who had a clinical diagnosis of erythema migrans. Quantitative PCR on skin biopsy-derived material was the most sensitive diagnostic method (80.9%), followed by 2-stage serologic testing of convalescent-phase samples (66.0%), conventional nested PCR (63.8%), skin culture (51.1%), blood culture (44.7%), and serologic testing of acute-phase samples (40.4%). Results of all assays were negative for 3 patients (6.4%). We conclude that the clinical diagnosis of erythema migrans is highly accurate in an area where B. burgdorferi is endemic if it is made by experienced health care personnel, but some patients with this diagnosis may not have B. burgdorferi infection. No single diagnostic modality is suitable for detection of B. burgdorferi in every patient with erythema migrans.

Biopsy↗

Borrelia lonestari infection after a bite by an Amblyomma americanum tick.

Erythematous rashes that are suggestive of early Lyme disease have been associated with the bite of Amblyomma americanum ticks, particularly in the southern United States. However, Borrelia burgdorferi, the causative agent of Lyme disease, has not been cultured from skin biopsy specimens from these patients, and diagnostic serum antibodies usually have not been found. Borrelia lonestari sp nov, an uncultured spirochete, has been detected in A. americanum ticks by DNA amplification techniques, but its role in human illness is unknown. We observed erythema migrans in a patient with an attached A. americanum tick. DNA amplification of the flagellin gene flaB produced B. lonestari sequences from the skin of the patient that were identical to those found in the attached tick. B. lonestari is a probable cause of erythema migrans in humans.

Aged↗

Primary papillary serous carcinoma of the peritoneum in a man.

BACKGROUND: Primary papillary serous carcinoma of the peritoneum is a well-known entity in women. The tumour is derived from the extraovarian mesothelium and the pelvis and lower abdomen mesothelia. The treatment strategies are similar to ovarian serous papillary carcinoma. PATIENTS AND METHODS: A case of primary serous papillary carcinoma of the peritoneum in a man is presented. The patient, 53 years old, died 2 months after diagnosis. RESULTS: The histologic and immunohistochemical studies of the tumour will be presented. These studies, made during lifetime and at autopsy of the patient, confirm a diagnosis of primary serous papillary carcinoma of the peritoneum. CONCLUSIONS: primary serous papillary carcinoma of the peritoneum can occur in men, and should be considered in the differential diagnosis in cases of abdominal carcinomatosis of unknown origin. Treatment options remain to be determined.

Antigens, Neoplasm↗

Asymptomatic Borrelia burgdorferi infection.

Little is known about the natural history of asymptomatic Borrelia burgdorferi infection. Our analysis of the asymptomatic infections diagnosed serologically in a recent OspA vaccine trial conducted in the United States (N Engl J Med 1998;339: 209-215), suggests that the natural history of this event is more benign than that reported for untreated patients with erythema migrans (Ann Intern Med 1987;107: 725-731). We hypothesize that this is due either to incorrect diagnosis since the specificity of the serologic criteria used to diagnose asymptomatic infection in the vaccine study is unknown, or to infection with non-pathogenic strains of B. burgdorferi. Increasing evidence indicates that the invasive potential of strains of B. burgdorferi varies according to the specific subtype. Theoretically, a serologic testing method could be devised which would distinguish infection with invasive versus non-invasive strains of B. burgdorferi, and allow testing of the second hypothesis.

Bacterial Vaccines↗

Impact of genotypic variation of Borrelia burgdorferi sensu stricto on kinetics of dissemination and severity of disease in C3H/HeJ mice.

Various genotypes of Borrelia burgdorferi sensu stricto have been previously identified among a large collection of isolates cultured from patients with Lyme disease in the United States. Furthermore, association of specific genotypes with hematogenous dissemination early in the disease course has been observed. The present study assessed kinetics of spirochete dissemination and disease severity in C3H/HeJ mice infected with two different genotypes of B. burgdorferi. Spirochete load in plasma and ear and other tissue samples of infected mice was measured by quantitative PCR, and these data were compared to those obtained by culture and histopathologic analysis. In mice infected with isolate BL206 (a type 1 strain), the peak number of spirochetes was observed in plasma between day 4 and 7, in heart and ear tissue on day 14, and in joints on day 28 postinoculation. There was a correlation between the peak number of spirochetes in plasma on day 4 or 7 and that in ear biopsy and joint specimens on day 14. By contrast, spirochete burdens in plasma of mice infected with isolate B356 (a type 3 strain) were 16- and 5-fold lower than those of BL206-infected mice on days 7 and 14 of infection, respectively. Similarly, approximately 6- and 13-fold fewer spirochetes were detected in the heart tissues of B356-infected mice compared to BL206-infected mice. Histopathologically, severe arthritis and aortitis were noted only in mice infected with isolate BL206. Spirochete dissemination and disease severity vary significantly in mice infected with distinct genotypes of B. burgdorferi, suggesting that genotypic differences in the infecting spirochetes play a key role in the pathogenesis and development of clinical disease.

Animals↗

Genetics and regulation of chitobiose utilization in Borrelia burgdorferi.

Borrelia burgdorferi spends a significant proportion of its life cycle within an ixodid tick, which has a cuticle containing chitin, a polymer of N-acetylglucosamine (GlcNAc). The B. burgdorferi celA, celB, and celC genes encode products homologous to transporters for cellobiose and chitobiose (the dimer subunit of chitin) in other bacteria, which could be useful for bacterial nutrient acquisition during growth within ticks. We found that chitobiose efficiently substituted for GlcNAc during bacterial growth in culture medium. We inactivated the celB gene, which encodes the putative membrane-spanning component of the transporter, and compared growth of the mutant in various media to that of its isogenic parent. The mutant was no longer able to utilize chitobiose, while neither the mutant nor the wild type can utilize cellobiose. We propose renaming the three genes chbA, chbB, and chbC, since they probably encode a chitobiose transporter. We also found that the chbC gene was regulated in response to growth temperature and during growth in medium lacking GlcNAc.

Acetylglucosamine↗

Characterization of Borrelia burgdorferi isolated from erythema migrans lesions: interrelationship of three molecular typing methods.

Genetic diversity among Borrelia burgdorferi isolates recovered from the skin of Lyme disease patients was assessed by ribosomal DNA (rDNA) spacer restriction fragment length polymorphism analysis, genomic restriction site polymorphism analysis, and plasmid content analysis. There was a significant association between the three rDNA spacer types, the six pulsed-field gel types, and plasmid content (P < 0.001). The association between distinct chromosomal and plasmid markers implies a clonal origin for each genotype.

Adult↗

Unique frequency of known mutations in Brazilian MPS I patients.

The frequency of 10 known mutations in the IDUA gene-Q70X, A75T, H82P, R89Q, 678-7 g-->a, L218P, A327P, R383H, W402X, and P533R-was estimated in a group of 24 index cases with mucopolysaccharidosis type I. Three affected relatives were also analysed. Six of the 10 mutations screened were present in our patients (Q70X, R89Q, A327P, R383H, W402X, and P533R). These mutations account for 54% of the alleles; 37% of the genotypes were defined. Frequencies of these mutations are markedly different from those in the literature. A novel combination Q70X/A327P is described. This was the first time Brazilian MPS I patients were analysed with molecular techniques. The low frequency of common mutations indicates that a more comprehensive analysis of the IDUA gene should be done to delineate the mutation profile of MPS I better in our population.

Brazil↗

Treatment of atopic eczema with oral mycophenolate mofetil.

BACKGROUND: Activated T and B lymphocytes are the predominant inflammatory cells in atopic eczema (AE) lesions. Mycophenolic acid, the active form of mycophenolate mofetil (MMF), blocks the proliferative responses of T and B lymphocytes. OBJECTIVES: In this pilot study, we examined the efficacy of MMF (CellCept(R), Hoffman La Roche, Grenzach-Wyhlen, Germany) in severe AE. METHODS: Ten patients with severe AE (severity index > 50) according to the Severity Scoring of Atopic Dermatitis (SCORAD) index were treated with oral MMF at an initial dose of 1 g daily during the first week and 2 g daily for a further 11 weeks. Laboratory examination including full blood count, lymphocyte subset analysis, serum immunoglobulins (IgE, IgG, IgM, IgA), total bilirubin, alkaline phosphatase, aminotransferases, lactate dehydrogenase and creatinine was performed every 2 weeks. Additionally, interleukin (IL)-10 and interferon (IFN)-gamma in serum were measured. RESULTS: None of the 10 patients who received MMF discontinued the trial because of lack of efficacy or adverse events. Compared with the baseline, the median scores for disease severity (SCORAD index) improved by 68% during treatment with MMF. The median serum IgE level decreased significantly, from 10,300 kU L-1 before treatment to 7830 kU L-1 after 12 weeks. MMF induced a significant increase in the T-helper (Th)-1-related cytokine IFN-gamma and a significant decrease in IL-10, mainly produced by Th2 cells. CONCLUSIONS: The present study demonstrates that oral MMF at a dose of 2 g daily is an effective, safe and well-tolerated immunosuppressive therapy for severe AE in adults.

Adult↗

Ehrlichiosis associated vasculitis.

OBJECTIVE: To test the hypothesis that some cases of primary vasculitis are caused by ehrlichiosis. DESIGN: A retrospective case study and serological analysis of stored sera. SETTING: University hospital. SUBJECTS: Fifty-five patients discharged with any type of vasculitis over a 6-year period. MAIN OUTCOME MEASURES: Serology for human monocytic ehrlichiosis, and the human granulocytic ehrlichiosis agent, and polymerase chain reaction (PCR) analysis of biopsy specimens. RESULTS: Three patients (5.5%) had titres of 1 : 128 or higher against E. chaffeensis; none was positive for the human granulocytic ehrlichiosis agent. Skin biopsies of these patients showed lesions compatible with polyarteritis nodosa, allergic purpura and unspecified vasculitis. PCR analysis of the biopsies was unrevealing. CONCLUSIONS: Infection with human monocytic ehrlichiosis may underlie some forms of vasculitis. If confirmed, these findings may help identify patients with vasculitis who would benefit from antibiotic treatment.

Adult↗

The importance of language and culture in pediatric care: case studies from the Latino community.

BACKGROUND: Few studies have examined culture's effect on pediatric care. OBJECTIVES: To analyze 3 cases illustrating the importance of culture in pediatrics. METHODS: Case analysis with a cultural competency model. RESULTS: No interpreter was available for the parents of a 3-year-old brought to the emergency department because of abdominal pain; she was discharged twice, returned with an acute abdomen, and was hospitalized for treatment of appendiceal rupture and peritonitis. A 2-year-old fractured her clavicle in a fall but was placed in social services' custody because of a pediatrician's misinterpretation. Parents of a ventilation-dependent 2-week-old with encephalopathy, seizures, and renal failure were unaware of the infant's poor prognosis, despite use of an interpreter. CONCLUSIONS: Culture can have a significant impact on pediatric care; use of a simple model can ensure that pediatricians provide culturally competent care.

Abdominal Pain↗