Cell Proliferation Kinetics of the Intramuscularly Implanted Lewis Lung Carcinoma

The growth kinetics of the Lewis lung carcinoma tumor was studied. The main proliferative parameters of an early stage of the growth (8th day after tumor implantation) were derived from the analysis of the growth curve and the fraction of labeled mitoses (FLM curve). The occurrence of proliferative changes due to the transplantation was confirmed. The main variations observed concern a shortening of the cell cycle time, a prolongation of the S phase duration and an increase in cell loss. A critical analysis of the results of this preliminary study is reported.

Cellular Delivery of Human Cntf Prevents Motor and Cognitive Dysfunction in a Rodent Model of Huntington's Disease

The delivery of ciliary neurotrophic factor (CNTF) to the central nervous system has recently been proposed as a potential means of halting or slowing the neural degeneration associated with Huntington's disease (HD). The following set of experiments examined, in detail, the ability of human CNTF (hCNTF) to prevent the onset of behavioral dysfunction in a rodent model of HD. A DHFR-based expression vector containing the hCNTF gene was transfected into a baby hamster kidney fibroblast cell line (BHK). Using a polymeric device, encapsulated BHK-control cells and those secreting hCNTF were transplanted bilaterally into rat lateral ventricles. Eight days later, the same animals received bilateral injections of quinolinic acid (QA, 225 nmol) into the previously implanted striata. A third group received sham surgery (incision only) and served as a normal control group. Bilateral infusions of QA produced a significant loss of body weight and mortality that was prevented by prior implantation with hCNTF-secreting cells. Moreover, QA produced a marked hyperactivity, an inability to use the forelimbs to retrieve food pellets in a staircase test, increased the latency of the rats to remove adhesive stimuli from their paws, and decreased the number of steps taken in a bracing test that assessed motor rigidity. Finally, the QA-infused animals were impaired in tests of cognitive function — the Morris water maze spatial learning task, and the delayed nonmatching-to-position operant test of working memory. Prior implantation with hCNTF-secreting cells prevented the onset of all the above deficits such that implanted animals were nondistinguishable from sham-lesioned controls. At the conclusion of behavioral testing, 19 days following QA, the animals were sacrificed for neurochemical determination of striatal choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD) levels. This analysis revealed that QA decreased striatal ChAT levels by 35% and striatal GAD levels by 45%. In contrast, hCNTF-treated animals did not exhibit any decrease in ChAT levels and only a 10% decrease in GAD levels. These results support the concepts that implants of polymer-encapsulated hCNTF-releasing cells can be used to protect striatal neurons from excitotoxic damage, produce extensive behavioral protection as a result of that neuronal sparing, and that this strategy may ultimately prove relevant for the treatment of HD.

Validation of the Composite Autonomic Symptom Score 31 (COMPASS 31) for the assessment of symptoms of autonomic neuropathy in people with diabetes

AIM

To validate the Composite Autonomic Symptom Score (COMPASS) 31, in its Italian version, for the diagnosis of diabetic cardiovascular autonomic neuropathy in a clinic-based, single-centre study.

METHODS

A total of 73 participants with diabetes (age 55 ± 14 years) completed the COMPASS 31 questionnaire before undergoing cardiovascular autonomic neuropathy and diabetic polyneuropathy assessment according to cardiovascular reflex tests, neuropathic symptoms and signs, and vibration and thermal thresholds.

RESULTS

The COMPASS 31 total weighted score differed between participants with and without cardiovascular autonomic neuropathy (29.9 ± 19.5 vs 16.1 ± 14.7; P = 0.003) and with and without diabetic polyneuropathy (28.9 ± 19.1 vs 12.7 ± 11.3; P < 0.0001). It was related to cardiovascular reflex tests score (rho = 0.38, P = 0.0013) as well as diabetic polyneuropathy symptoms (rho=0.61, P < 0.0001) and signs scores (rho = 0.49, P < 0.0001). Receiver-operating curve analysis showed a fair diagnostic accuracy of total score for cardiovascular autonomic neuropathy (area under the curve 0.748 ± 0.068, 95% CI 0.599-0.861) and diabetic polyneuropathy (area under the curve 0.742 ± 0.061, 95% CI 0.611-0.845). The best score thresholds were 16 for early cardiovascular autonomic neuropathy (sensitivity 75.0%, specificity 64.9%, positive predictive value 37.5% and negative predictive value 90.2%), and 17 for both confirmed cardiovascular autonomic neuropathy and diabetic polyneuropathy (sensitivity 70.0% and 65.5%, respectively; specificity 66.7% and 79.5%, respectively; positive predictive value 25.0% and 67.9%, respectively; and negative predictive value 93.0% and 77.8%, respectively). COMPASS 31 had a good internal consistency according to Cronbach's α coefficient of 0.73.

CONCLUSIONS

COMPASS 31 can represent a valid, easy-to-use, quantitative assessment tool for autonomic symptoms in diabetic neuropathy, with a fair diagnostic accuracy for both cardiovascular autonomic neuropathy and diabetic polyneuropathy.

Gut-borne Saccharomyces cerevisiae, a promising candidate for the formulation of feed additives, modulates immune system and gut microbiota

The aim was to evaluate the effect of Saccharomyces cerevisiae RC016 on immune parameters and gut microbiota in healthy mice. Animals received S. cerevisiae RC016 for 10 days. Microbial translocation to liver and changes in some bacterial populations in caecum were determined. Immune stimulation was assessed at gut level (measure of immunoglobulin A (IgA)+ cells and luminal cytokine profile) and by evaluating the activity of peritoneal macrophages. Oral administration of S. cerevisiae RC016 did not induce microbial translocation to liver. Mice that received yeast increased the number of IgA+ cells in their intestines, the phagocytic activity of peritoneal macrophages and decreased tumour necrosis factor alpha (TNF-α) levels in the small intestine with increases of interleukin-10/TNF-αratio. Administration of S. cerevisiae RC016 caused the decline of a logarithmic unit for Enterobacteriaceae counts compared to the control. The immune and gut microbiota modulation observed demonstrates that S. cerevisiae RC016 is a promising candidate for the formulation of feed additives to improve animal productivity. The beneficial in vivo effects observed for the potential probiotic S. cerevisiae RC016 with previously reported mycotoxin-binding properties, demonstrated that this strain could be suitable to be included in a novel product to improve animal productivity, with both probiotic and mycotoxin-binding properties. However, studies in the specific host will be necessary to confirm this potential.

Lactobacillus rhamnosus RC007 intended for feed additive: immune-stimulatory properties and ameliorating effects on TNBS-induced colitis

Lactobacillus rhamnosus RC007 is a potential probiotic bacterium that can exert beneficial effects as supplement for animal feed, by improving the immune status in healthy host, and by providing therapeutic benefits to infected/inflamed animals. The aim of the present work was to evaluate in vivo the beneficial properties of L. rhamnosus RC007, intended for animal feed, when administered to healthy and trinitro-benzene-sulfonic-acid (TNBS) colitis induced BALB/c mice. The administration of L. rhamnosus RC007 to healthy mice during 10 days increased the phagocytic activity of peritoneal macrophages and the number of immunoglobulin A+ cells in the lamina proper of the small intestine. Significant increases of monocyte chemotactic protein 1, interleukin (IL)-10 and tumour necrosis factor alpha (TNF-α) concentrations, and in the ratio between anti- and pro-inflammatory cytokines (IL-10/TNF-α) were observed in intestinal fluids after administration of bacteria. In the inflammation model, less body weight loss, macroscopic and histological damages in the large intestine were accompanied by increased IL-10/TNF-α ratio in the intestinal fluids of mice from the L. rhamnosus-TNBS group when compared to the TNBS group. In a healthy host, the oral administration of L. rhamnosus RC007 kept the gut immune system stimulated allowing a faster response to noxious stimulus. Mice that received L. rhamnosus RC007 also decreased the severity of the intestinal inflammation.