Naturally Developing Virus-Induced Lethal Pneumonia in Two Guinea Pigs (Cavia porcellus).

Two guinea pigs (Cavia porcellus) were affected by an acute naturally developing lethal pneumonitis. One guinea pig was found dead and had not had clinical signs of disease, whereas the second guinea pig was dyspneic and tachypneic. Necropsy revealed well-demarcated areas of pulmonary consolidation in the cranial and ventral areas of the lungs.

Prolactin receptor gene expression in the forebrain of pregnant and lactating rats.

Prolactin plays a large role in the onset of maternal behavior at parturition. Knowledge of the change in expression of the prolactin receptor in the brain across pregnancy and lactation, however, is limited. Prolactin receptor gene expression was determined by in situ hybridization histochemistry during pregnancy and lactation in rats.

A high isoflavone soy protein diet and intravenous genistein delay rejection of rat cardiac allografts.

Genistein, a soy isoflavone, has in vitro immunosuppressive properties. We investigated whether genistein or dietary soy protein containing isoflavones could influence the outcome of rat cardiac allografts. Lewis rats were fed a diet with protein from high isoflavone soy protein fraction (HIS), casein (CAS) or casein with isoflavones added (CI) starting 1 wk before heart transplants from Wistar Furth donors, and continuing throughout the study.

Exposure-disease continuum for 2-chloro-2'-deoxyadenosine (2-CdA), a prototype teratogen: induction of lumbar hernia in the rat and species comparison for the teratogenic responses.

Background: The purine analog 2-chloro-2'-deoxyadenosine (2-CdA) caused ocular and limb defects in the mouse and rabbit. The current study examined the teratogenic potential of this drug in the rat and compared the adverse developmental outcomes with the other species.

Methods: Timed-pregnant Sprague-Dawley rats were given a single intraperitoneal injection of various doses of 2-CdA ranging from 5-60 mg/kg, at gestational day (GD) 9.

An outbreak of Rift Valley fever in Northeastern Kenya, 1997-98.

In December 1997, 170 hemorrhagic fever-associated deaths were reported in Garissa District, Kenya. Laboratory testing identified evidence of acute Rift Valley fever virus (RVFV). Of the 171 persons enrolled in a cross-sectional study, 31(18%) were anti-RVFV immunoglobulin (Ig) M positive.

The Trp53 hemizygous mouse in pharmaceutical development: points to consider for pathologists.

ILSI-HESI sponsored an international consortium for the evaluation of alternative models, including the TrpS3+/- mouse. for use in short-term carcinogenicity testing of pharmaceuticals. Products of the ILSI evaluation included guidance for protocol design and assay interpretation, spontaneous tumor incidences, diagnostic criteria for common proliferative lesions, and results of assays for pharmaceutical agents that are known human and/or rodent carcinogens and non-carcinogens.

The impact of clozapine on electrophysiological features: how can we utilize the findings?

Introduction: There is a large body of findings on the impact of clozapine upon electrophysiological features. This study repeats several of these earlier studies and reports on whether, and how, these findings can be utilized in our particular research/clinical situation.

Methods: Neurophysiological investigations were carried out on 37 schizophrenia patients, before and after commencing a clinically indicated trial of clozapine.

Lactogenic hormone regulation of maternal behavior.

Biological factors can profoundly affect a mother's response to her young. For example, it is well known that the hormones of pregnancy act on the maternal brain to stimulate the spontaneous onset of maternal behavior at parturition. Studies in the rat have provided an excellent model to investigate maternal behavior in mammals, since maternal behavior in rats is easily observable and readily quantifiable and it is well-documented that the endocrine state of gestation helps to bring about the onset of maternal behavior around the time of birth.

EmtA, a rRNA methyltransferase conferring high-level evernimicin resistance.

Enterococcus faecium strain 9631355 was isolated from animal sources on the basis of its resistance to the growth promotant avilamycin. The strain also exhibited high-level resistance to evernimicin, a drug undergoing evaluation as a therapeutic agent in humans. Ribosomes from strain 9631355 exhibited a dramatic reduction in evernimicin binding, shown by both cell-free translation assays and direct-binding assays.

The influence of growth hormone replacement on heart rate variability in adults with growth hormone deficiency.

Objective: Growth hormone (GH) deficiency is associated with increased cardiovascular morbidity and mortality. Abnormalities in heart rate variability (HRV), a surrogate marker of cardiac autonomic tone, have also been found in untreated growth hormone deficient (GHD) patients. Similar abnormalities have been found in patients with complications postmyocardial infarction.

Combined phenyl silane and immunoaffinity column cleanup with liquid chromatography for determination of ochratoxin A in roasted coffee: collaborative study.

A collaborative study was conducted to evaluate a liquid chromatography (LC) method for ochratoxin A using sequential phenyl silane and immunoaffinity column cleanup. The method was tested at 3 different levels of ochratoxin A in roasted coffee, which spanned the range of possible future European regulatory limits. The test portion was extracted with methanol and sodium bicarbonate by shaking for 30 min.

Mobile lipid production after confluence and pH stress in perfused C6 cells.

NMR-visible mobile lipid (ML) has been observed in aggressive tumors and also in in vitro tumor cell models subjected to growth-inhibiting conditions, such as confluence or low-pH stress. The aim of the present study was to determine if ML production after confluence or low pH stress in a cultured cell model of brain tumor is due to growth arrest alone. ML was observed in situ by one- and two-dimensional (1)H NMR in viable but growth-arrested C6 glioma cells superfused for a period of 48 h after harvesting.

Mitogen immunotherapy for HIV infections exemplified by phytohemagglutinin and pokeweed mitogen.

The ideal treatment for HIV infections would supplement highly active antiretroviral therapy (HAART) started at the time of initial diagnosis with an agent that can facilitate cure in the briefest time possible to avoid adverse effects of extended HAART such as drug toxicity, noncompliance, and shortened telomere-induced replicative senescence of CD8 cells. As a crucial part of the regimen, the agent must be able to initiate killer reactions against the HIV, replenish CD4 cells, rejuvenate CD8 cells, block HIV invasion of CD4 cells, activate latent HIV-sequestering host cells, stimulate effective immune reactions against malignancies, generate effective immune responses against conventional and opportunistic infections, circumvent the treatment- and immune response-evading capacities of HIV mutations, and reconstitute immune and hematopoietic competences. Over the past decade, the L4 isolectin of PHA has been presented as a mitogen capable of meeting these goals as they have become defined, but its potential has not been recognized sufficiently to expedite its evaluation.

Liquid chromatographic method with immunoaffinity column cleanup for determination of ochratoxin A in barley: collaborative study.

A collaborative study was conducted to evaluate a liquid chromatographic (LC) method with immunoaffinity column cleanup for determination of ochratoxin A. The method was tested at 3 concentration levels of ochratoxin A in barley, which represent possible future European regulatory limits. The test portion was extracted with acetonitrile-water by blending at high speed.

Effects of mutations in ribosomal protein L16 on susceptibility and accumulation of evernimicin.

Chemical mutagenesis of Staphylococcus aureus RN450 generated two strains that displayed a stable reduction (30- to 60-fold) in susceptibility to evernimicin. Cell-free translation reactions demonstrated that the resistance determinant was located in the ribosomal fraction. Compared to ribosomes isolated from a wild-type strain, ribosomes from the mutant strains displayed an 8- to 10-fold reduction in affinity for [(14)C]evernimicin.

Independent endocytosis of the NK(1) and NK(3) tachykinin receptors in neurons of the rat myenteric plexus.

In the myenteric plexus of rat ileum, NK(1) and NK(3) receptors are co-located almost exclusively on neurons of a single population. This study compares endocytosis of NK(1) and NK(3) receptors in these neurons. In the absence of agonist, 26.

Cellular and molecular mechanisms of action of linuron: an antiandrogenic herbicide that produces reproductive malformations in male rats.

Antiandrogenic chemicals alter sex differentiation by several different mechanisms. Some, like flutamide, procymidone, or vinclozolin compete with androgens for the androgen receptor (AR), inhibit AR-DNA binding, and alter androgen-dependent gene expression in vivo and in vitro. Finasteride and some phthalate esters demasculinize male rats by inhibiting fetal androgen synthesis.

Interlaboratory comparison of the CB6F1-Tg rasH2 rapid carcinogenicity testing model.

Several genetically engineered mouse models are currently being examined for potential use in cancer hazard identification. We have undertaken an interlaboratory comparison of the performance of the CB6F1-Tg rasH2 transgenic mouse in cancer bioassays concurrently conducted in the United States and Japan. Chemicals selected for study included known human carcinogens (melphalan and cyclosporin A) and known rodent carcinogens (p-cresidine and vinyl carbamate) tested at carcinogenic doses, and non-carcinogens (p-anisidine and resorcinol) tested at appropriate high doses.

Apparent pokeweed mitogen cure of metastatic gum melanoma in an older dog.

Immunotherapy with plant mitogens has been of increasing interest to both authors, although their mutual attraction to these substances over the past two decades occurred independently and has taken divergent pathways from the start. Because of their clinical unavailability, Wimer's efforts have been confined to writing theoretical concepts on potential applications of the mitogens focusing on the L4 isolectin of PHA. Alternatively, Mann has worked actively with laboratory and experimental research involving PWM that he has extracted himself.

Evernimicin binds exclusively to the 50S ribosomal subunit and inhibits translation in cell-free systems derived from both gram-positive and gram-negative bacteria.

Evernimicin (SCH 27899) is a new antibiotic with activity against a wide spectrum of gram-positive bacteria and activity against some gram-negative bacteria. Previous metabolic labeling studies indicated that evernimicin specifically inhibited protein synthesis in Staphylococcus aureus. Using a susceptible Escherichia coli strain, we demonstrated that evernimicin also inhibited protein synthesis in E.

Abnormal heart rate variability in adults with growth hormone deficiency.

GH-deficient (GHD) patients have increased risk of cardiovascular death and may have cardiac structural abnormalities. In non-GHD patients these are associated with cardiac autonomic dysfunction, and it is possible that autonomic dysfunction is also present in GHD patients. Power spectral analysis (PSA) of heart rate variability (HRV) indirectly measures cardiac autonomic tone and generates peaks at 3 frequency bands, very low frequency (VLF), low frequency (LF) and high frequency (HF).