Developmental expression and location of IGF-I and IGF-II mRNA and protein in skeletal muscle

To investigate the role of IGF in muscle development in vivo, developmental expression and location of IGF-I and -II protein and mRNA were examined in fetal, postnatal, and adult skeletal muscle. Muscle tissue was collected from 30-, 44-, 59-, 68-, 75-, 89-, and 109-d porcine fetuses, 21-d neonatal pigs, and 6-mo-old (adult) pigs. Relative amounts of IGF-II mRNA peaked (P < .05) in 59-d fetal muscle and decreased thereafter. Inversely, muscle IGF-I expression increased (P < .05) to maximal levels around birth. For in situ hybridization, frozen muscle tissue sections (10 microm) were hybridized with a hydrolyzed form of the same riboprobes or incubated with polyclonal or monoclonal antibodies to IGF-I or -II, respectively. The majority of IGF-I and IGF-II mRNA was localized to developing muscle fibers, whereas little signal was found in the surrounding connective tissues. Immunofluorescent localization of IGF-I and -II confirmed that muscle IGF are present in developing muscle fibers. Collectively, these data show that IGF-I and -II are expressed and produced primarily in muscle cells within developing muscle tissue and support the hypothesis that IGF-I and -II modulate fetal muscle development.     

Involvement of interleukin-3 in delayed-type hypersensitivity

The in vivo functions of interleukin-3 (IL-3) were investigated by generating IL-3-deficient mice. Although hematopoiesis was unimpaired in homozygous mutant animals, contact hypersensitivity reactions were compromised. IL-3 was required for efficient priming of hapten-specific contact hypersensitivity responses, but was dispensable for T-cell-dependent sensitization to tumor cells. These findings reveal a critical role for IL-3 in some forms of delayed-type hypersensitivity.     

Molecular typing of Borrelia burgdorferi from Lyme disease patients by PCR-restriction fragment length polymorphism analysis

Ninety-three Borrelia burgdorferi isolates obtained from erythema migrans lesions or blood of Lyme disease patients in Westchester County, N.Y., between 1991 and 1994 were characterized by PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the 16S-23S rRNA gene spacer. All isolates could be classified into three distinct RFLP types. Among the 82 skin biopsy isolates studied, 21 (25.6%) were type 1, 37 (45.1%) were type 2, and 21 (25.6%) were type 3. Three (3.7%) cultures contained a mixture of two isolates with distinct RFLP types. The 11 isolates cultured from blood showed a similar predominance of RFLP type 2 (6 of 11; 54.5%) relative to types 1 (2 of 11; 18.2%) and 3 (3 of 11; 27.3%). For one patient both skin and blood isolates were cultured, and RFLP analysis revealed that these isolates differed from one another. This study demonstrates that there is genotypic heterogeneity in B. burgdorferi strains infecting Lyme disease patients, and this typing approach may allow differentiation of isolates with various degrees of pathogenic potential.     

Increased levels of plasma cholesteryl ester hydroperoxides in patients with subarachnoid hemorrhage

The pathophysiology of subarachnoid hemorrhage (SAH) may involve free radical production and lipid peroxidation. We examined plasma levels of cholesteryl ester hydroperoxides (CEOOH) and antioxidants in 25 patients with SAH, and 10 neurologic controls with lacunar stroke. Patients with SAH had significantly increased plasma levels of CEOOH, which peaked on day 5 after the ictus. Concentrations of CEOOH were significantly increased, and ascorbic acid concentrations were significantly decreased in patients who developed vasospasm compared with patients without vasospasm. Increased levels of CEOOH were associated with increased mortality and correlated with clinical outcome scales. These results implicate oxidative stress in the pathogenesis of SAH and suggest that measurements of CEOOH in plasma may be useful both prognostically as well as in monitoring therapeutic interventions.     

Real-time acquisition and data analysis of skeletal muscle contraction in a multi-user environment

A data acquisition system is described which acquires data from contracting skeletal muscle. The system is designed to run in a multi-user environment while acquiring contractile data in real-time. Time dedicated solely to laboratory experiments is thus eliminated. A menu-driver is included to allow users to enter experimental commands with or without command arguments. Error monitoring functions prevent operator errors from causing data loss. Data storage in both ASCII and binary formats maximizes file flexibility, readability and accessibility. Finally, an on-line tutorial and help facility is provided for user training. The system developed is applicable to any experimental environment involving data acquisition, storage and analysis.     

Chromosomal anomalies in stage D1 prostate adenocarcinoma primary tumors and lymph node metastases detected by fluorescence in situ hybridization

We previously reported a HPLC assay method using fluorimetric detection for the simultaneous determination of urinary N2-(3-aminopropyl)biopterin (oncopterin, a natural pteridine newly found in urine from cancer patients), biopterin and neopterin. We now have observed that an unknown substance, which may be derived from methotrexate, in urine from a patient with stomach cancer interfered with the assay of oncopterin and demonstrated that oncopterin could be completely separated from the unidentified substance by HPLC using a Nucleosil 100-5SA strong cation-exchange column. Furthermore, oncopterin was not detectable by this HPLC-fluorimetric method in urine samples from patients with stomach cancer who were not treated with methotrexate. The content of urinary oncopterin from cancer patients is supposed to be very low, with less than 1 mumol/mol creatinine. The present results indicate that the peak found with elution from the C18 column was a methotrexate-derived compound and co-eluted with the analyte oncopterin.