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The effect of gossypol on fast axonal transport and microtubule assembly

Gossypol at micromolar concentrations (2 μM) was found to inhibit axonal transport and a microsomal ATPase activity in the frog sciatic nerve, although axonal microtubules and the neuronal content of AMP, ADP and ATP were not affected. At slightly higher concentrations (30-40 μM), gossypol also inhibited microtubule assembly and neuronal energy metabolism. Gossypol accumulated in the nerve and the

Calmodulin‐Binding Proteins Within the Slow Phase of Axonal Transport in the Rabbit Vagus Nerve Per Ekstrom and Martin Kanje

Abstract: : Calmodulin‐binding proteins (CBPs) in the rabbit vagus nerve were studied by means of calmodulin‐Sepha‐rose affinity chromatography and polyacrylamide gel electrophoresis. The soluble fraction (105g supernatant) of a nerve homogenate contained four CBPs with molecular weights of 44, 55, 91, and 93 kD, respectively. Slowly transported proteins were recovered in the vagus 3 days after in

The effects of trifluoperazine on fast and slow axonal transport in the rabbit vagus nerve

The effects of trifluoperazine (TFP) on fast and slow axonal transport (AXT) of labeled proteins were examined in the rabbit vagus nerve. Cuffs soaked in a 10 mM, but not 0.1 mM or 1 mM, concentration of TFP applied locally around the vagus nerve in vivo blocked both fast and slow AXT, as measured by the accumulation of 3H‐labeled proteins. In vitro, fast AXT was affected by 0.1 mM TFP. The TFP cu

The use of the regenerating frog sciatic nerve for pharmacological studies of orthograde and retrograde axonal transport

The outgrowth region of the regenerating frog sciatic nerve shows an increased permeability for various drugs, which has been utilized for pharmacological studies of axonal transport. Six days after a bilateral crush lesion, the nerves, including the spinal ganglia, were incubated in a compartmented chamber. Orthograde transport was assessed from the proximodistal distribution and the accumulation

Family History and Probability of Prostate Cancer, Differentiated by Risk Category : A Nationwide Population-Based Study

Background: Familial prostate cancer risk estimates are inflated by clinically insignificant low-risk cancer, diagnosed after prostate-specific antigen testing. We provide age-specific probabilities of non-low- and high-risk prostate cancer. Methods: Fifty-one thousand, eight hundred ninety-seven brothers of 32 807 men with prostate cancer were identified in Prostate Cancer data Base Sweden (PCBaS

Nerve regeneration and serum levels of insulin-like growth factor-I in rats with streptozotocin-induced insulin deficiency

Peripheral nerve regeneration was studied in female Sprague-Dawley rats with streptozotocin-induced insulin deficiency. Nerve regeneration was provoked by a crush lesion on the sciatic nerve 21 days after the streptozotocin injection. The regeneration was assessed by a pinch test at different time-points after injury. The rate ofregeneration in insulin-deficient animals, 2.5 mm/day, was significan

Impaired nerve regeneration in streptozotocin-diabetic rats. Effects of treatment with an aldose reductase inhibitor

Rats with streptozotocin-induced diabetes have a decreased rate of sciatic nerve regeneration. We studied the effects on this defect of treatment with the aldose reductase inhibitor, ponalrestat (25 mg/kg per day via an endogastric tube). The nerves of diabetic rats were crush-injured at 5 weeks of diabetes and regeneration evaluated 7 days later with the pinch-reflex test. Ponalrestat treatment w

Impaired nerve regeneration in streptozotocin-diabetic rats is improved by treatment with gangliosides

The rate of sciatic nerve regeneration and the effect of ganglioside treatment thereon were studied in the streptozotocin-diabetic rat. Two experimental protocols were used. In the first, sciatic nerves were crushed at 3 weeks of diabetes and treatment with purified bovine brain gangliosides (10 mg/kg/day ip) was begun the day before crush. In the second, nerves were crushed at 5 weeks of diabetes

Regeneration in vitro of the adult frog sciatic sensory axons

The adult frog sciatic nerve offers several advantages as an in vitro model to study nerve regeneration. The nerve with the attached dorsal root ganglia can easily be isolated and incubated in a culture medium for several days. If the nerve is subjected to a crush immediately after dissection there is a delay of 3.4 days after which the sensory axons start to regenerate into the distal nerve stump

A calmodulin inhibitor with high specificity compound 48/80, inhibits axonal transport in frog nerves without disruption of axonal microtubules

The calmodulin inhibitor compound 48/80 has previously been shown to arrest axonal transport in vitro in the regenerating frog sciatic nerve. The inhibition was limited to the outgrowth region of nerves, which had been allowed to regenerate in vivo for 6 days after a crush lesion, before they were incubated with or without drugs in vitro overnight. The effects of compound 48/80 on the regenerating

Insulin stimulates ganglionic protein synthesis and reduces thymidine incorporation in support cells of the in vitro regenerating adult frog sciatic sensory neurons

Insulin was tested for effects on crush injured, in vitro regenerating, adult frog sciatic sensory axons. A wide range of insulin concentrations (0.01-10 μg × ml-1) was found to stimulate incorporation of radioactive leucine into ganglionic protein by 50-80%. without affecting the regeneration distance. Simultaneously insulin inhibited the proliferation of the support cells at the crush region by

Primary triage nurses do not divert patients away from the emergency department at times of high in-hospital bed occupancy - a retrospective cohort study

Background: Emergency department (ED) overcrowding is frequently described in terms of input- throughput and output. In order to reduce ED input, a concept called primary triage has been introduced in several Swedish EDs. In short, primary triage means that a nurse separately evaluates patients who present in the Emergency Department (ED) and either refers them to primary care or discharges them h

A Fast Axonally Transported Protein of the Frog Sciatic Sensory Axons Undergoes Similar Qualitative Changes During Regeneration In Vitro and In Vivo

The adult frog sciatic sensory neurons have been shown to regenerate in vitro. If a crush injury is made at the beginning of culture, regeneration starts after 3.4 days and proceeds at a rate of ∼0.8 mm/day for several days. Two‐dimensional gel electrophoresis was used to study the patterns of radiolabeled, fast axonally transported proteins during the first 7 days of regeneration. Interest was fo

Effects of protein kinase inhibitors on regeneration in vitro of adult frog sciatic sensory axons

The effects of protein kinase inhibitors on regeneration in vitro of adult frog sciatic sensory axons were tested. Regeneration of crush‐injured nerves for 8 days in serum‐free medium was inhibited by staurosporine (100 nM) and H‐7 (100 μM), which are both known to inhibit protein kinase C. With the use of a compartmented culture system it could be shown that H‐7 exerted both local (outgrowth regi

Growth cones of regenerating adult sciatic sensory axons release axonally transported proteins

Labelled, rapidly transported axonal proteins were shown to be released frog adult frog sciatic sensory neurons, regenerating in vitro after a crush injury. The spatial distribution of the transported, released proteins could accurately be resolved by culturing the nerve on nitrocellulose paper, which trapped the released proteins. The release was located to the crush and to the entire outgrowth r

Adenosine inhibition of the regeneration in vitro of adult frog sciatic sensory axons

The sensory axons of the adult frog sciatic nerve have earlier been shown to regenerate in vitro. If a local test crush is made at the initiation of culturing, regeneration starts after 3.4 days and proceeds at a rate of about 0.8-0.9 mm/day for several days. In the present experiments regeneration was inhibited by adenosine in a reversible and dose-dependent fashion. Similarly, both an adenosine

Time‐dependent effects of insulin on Schwann cell proliferation in the in vitro regenerating adult frog sciatic nerve

The present study showed that insulin (0.01 μg/ml, ≈︂ 2 nM) inhibited [3H]‐thymidine incorporation in support cells, most likely Schwann cells, of the cultured frog sciatic nerve. A 25–35% inhibition took place in regenerating nerve preparations as well as in preparations devoid of neuronal protein synthesis, i.e., in isolated 5 mm nerve segments and in gangliectomized nerves, suggesting that the

Effects of phenothiazines and dibenzazepines on axonal transport and microtubule assembly in vitro

Various phenothiazines (thioridazine, trifluoperazine and chlorpromazine) and dibenzazepines (lofepramine, amitriptyline and desipramine) were studied for effects on fast axonal transport (AXT) in vitro in frog sciatic nerves. AXT, measured as the accumulation of (3H) leucine‐labelled proteins in front of a ligature, was inhibited by more then 50% by all the drugs tested at 0.2 mM concentrations.

Insulin and IGF-II, but not IGF-I, stimulate the in vitro regeneration of adult frog sciatic sensory axons

We used the in vitro regenerating frog sciatic nerve to look for effects of insulin and insulin-like growth factors I and II (IGF-I, IGF-II) on regeneration of sensory axons and on injury induced support cell proliferation in the outgrowth region. In nerves cultured for 11 days, a physiological dose (10 ng/ml, ≈ nM) of insulin or IGF-II increased ganglionic protein synthesis (by 20% and 50%, respe