Motor, but not sensory, cortical potentials are amplified by high-protein diet.

Animals fed a high-protein diet (50% casein) are hyperactive and more responsive to nociceptive stimuli than those fed either a normal- or low-protein diet. The mechanisms mediating dietary protein-induced behavior are unknown and may include both central and peripheral neural effects. Adult, Sprague-Dawley rats were fed 50% casein (treatment group) and 24% casein (control group) ad lib for 36-40 weeks. The animals were anesthetized with alpha-chloralose and urethane (50 mg/kg and 1.5 mg/kg, IP). EEG recordings were averaged while the anesthetized animal was conditioned using an alerting stimulus-imperative stimulus (AS-IS) paradigm. AS consisted of a 1.5 kHz, 90 dB tone cue. This was followed 2 seconds later by IS, an electrical tail stimulation (11 V, 1.4 s duration). Two negative deflections (N1 and N2) were generated by the frontal cortex during the AS-IS interstimulus interval. N1, an alerting response, was not different between the two groups. N2 amplitude and peak latency were significantly increased in the high-protein group (205% and 117% of control, respectively; p less than 0.05). N2 represents the activation of cells in the motor cortex. Brainstem auditory-evoked responses and somatosensory-evoked potentials also were recorded, but no differences were observed between the two diet groups. These data suggest that consumption of a high-protein diet results in an increase in central arousal mechanisms (measured by cortical negativity response), specifically involving increased excitability of the motor cortex, that is not associated with a disorder of information processing in the cerebral cortex (measured by brainstem auditory-evoked responses and somatosensory-evoked potentials).     

Effect of shunt surgery on spleen size, portal pressure and oesophageal varices in patients with non-cirrhotic portal hypertension

Shunt surgery is considered to be the treatment of choice in patients with non-cirrhotic portal hypertension. There is little data on the effect of side-to-side lieno-renal (SSLR) shunt on oesophageal variceal size, splenic size and splenic pulp pressure (SPP) in patients with non-cirrhotic portal hypertension. We evaluated pre- and postoperatively endoscopic grading of varices, splenic size and SPP for predicting shunt patency in 86 patients with non-cirrhotic portal hypertension: 56 with extrahepatic portal venous obstruction (EHPVO) and 30 with non-cirrhotic portal fibrosis (NCPF). The EHPVO patients with patent shunts (n= 47) showed significant reduction in SPP (pre-operative 43.56±7.9 vs postoperative 29.96±7.7 cm of saline), splenic size (6.5±2.8 vs 4.00±2.6 cm below costal margin) and varices grades (2.96±0.5 vs 0.92±0.8). Patients with blocked shunt (n= 9) did not show significant reduction in SPP and varices grades. However, there was reduction in spleen size (8.6±3.0 vs 6.3±4.3). In the NCPF group, 28 had patent shunts and showed significant reduction in SPP (46.3±13.5 vs 33.8±7.6 cm of saline), splenic size (9.1±3.3 vs 6.8±4.6 cm below costal margin) and varices grades (2.8±0.7 vs 1.05±0.96). As only two patients with NCPF had blocked shunts, no statistical comparison between patients with patent and patients with blocked shunts could be done. In conclusion, following SSLR, there is a significant reduction in SPP and varices grades in patients with patent shunts. Endoscopic grading of varices can be used to predict shunt patency. However, spleen size is not a good criteria for predicting shunt patency.     

Atrazine Toxicity on Hydromineral Balance of Fish, Tilapia mossambicus

The chronic effects of atrazine on total body weight, hydration level, and serum inorganic electrolytes in the tissues of freshwater fish, Tilapia mossambicus, were studied. Significant changes were observed in the tissues indicating the disturbances in the hydromineral balance of the fish as a consequence of atrazine.     

Decreased striatal D2 dopamine receptors in obese Zucker rats: changes during aging

The specific binding of [³H]YM-09151-2 was used to investigate the possible differences in age-associated changes in striatal D₂ dopamine (DA) receptor properties in genetically obese (fa/fa) Zucker rats and their lean3(Fa/?) littermates. The maximal binding sites (B_max) of D₂ DA receptors was found to decline with age in both obese and lean rats: the rate of decline in receptor B_max was slightly higher in lean than obese rats. However. the B_max of D₂ DA receptor in 6-, 12- and 18-month-old obese rats was significantly lower compared to the age-matched lean rats. These data indicate that obesity decreases the number of striatal D₂ DA receptors without affecting the rate at which receptor number decreases with age.     

Release of oral submucous fibrosis and reconstruction using superficial temporal fascia flap and split skin graft--a new technique.

Long standing oral submucous fibrosis is associated with involvement of the oral submucosa and the muscles of mastication leading to difficulty in mouth opening. Various surgical modalities are mentioned for release but each has its own limitations. This article introduces a new technique of release of submucous fibrosis and reconstruction using superficial temporal fascia flap and split skin graft. The surgical technique involves a pre-auricular incision extending into the temporal region with dissection carried out in the sub follicular plane to develop the superficial temporal fascia flap to its maximum extent. The masseter muscle origin is released from the zygomatic arch and the temporalis muscle insertion is released from the coronoid process through an external approach. The entire fibrosed mucosa is released intraorally to create a mucomuscular defect thus achieving full mouth opening. The superficial temporal fascia flap is then brought in and sutured to the intraoral defect, which is then covered with a split thickness skin graft. This procedure is performed bilaterally. A total of five patients were treated with this new technique and all of them showed good mouth opening in long term follow up. There was no donor site morbidity. The incision line is well hidden in the hair bearing area. A well vascularised superficial temporal fascia flap brings in good blood supply to the area of affected muscle and mucosa to improve its function.     

Modification of the hyperthermic response on neuroblastoma cells by cAMP and sodium butyrate

The role of adenosine 3',5'-cyclic monophosphate (cAMP) and sodium butyrate in modifying the effect of heat on murine neuroblastoma cells (NBP2) in culture was evaluated on the criterion of survival. An elevation of cellular cAMP level by prostaglandin (PG) A2, a stimulator of adenylate cyclase, and 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (R020-1724), an inhibitor of cyclic nucleotide phosphodiesterase, only during heat treatment (43 degrees C and 40 degrees C) was sufficient to enhance the effect of heat. The extent of enhancement (additive versus synergistic) depended upon the cAMP stimulating agent and the experimental condition. When these agents were added after heat treatment for the entire observation period, they produced similar results. PGA2 and R020-1724 are known to increase the intracellular level of cAMP in these cells by three and fivefold, respectively; therefore, the effect of these agents in enhancing the heat-response may be mediated by cAMP-dependent mechanisms. The presence of sodium butyrate during heat treatment alone was ineffective; however, when it was added before or after heat treatment for the entire observation period, the survival of heated cell was markedly reduced.     

Labetalol and nifedipine in the management of essential hypertension

Antihypertensive effects of labetalol and nifedipine were evaluated in a double blind cross over trial in ambulatory patients with moderately severe hypertension (mean diastolic BP 101.2 +/- 1.78 mm Hg, 105 +/- 2.15 mm Hg respectively and mean systolic BP 164.2 +/- 4.2 mm Hg and 171.4 +/- 5.82 mm Hg respectively in each group of 10 patients). The effect of labetalol over the systolic and diastolic BP was highly significant (p less than 0.01). The effects of nifedipine on systolic and diastolic BP were also significant but effects on diastolic BP was highly significant (p less than 0.01). In cross over study it was seen that nifedipine was not much superior in lowering the systolic BP whereas diastolic BP was lowered to a significant level (p less than 0.05) as compared to labetalol.