Inhaled lidocaine for prevention of hemodynamic changes in laryngoscopy and intubation

This study was undertaken to examine the efficacy of lidocaine aerosol pretreatment in attenuating hemodynamic (HD) responses secondary to laryngoscopy and tracheal intubation in patients undergoing surgery for intracranial space occupying lesions (ICSOL). A semiclosed breathing system was improvised to generate aerosol of consistent density. Five percent lidocaine was nebulized in two different dosages (0.2 and 0.1 ml/kg in groups A and B, respectively); group C (control) received aerosol of normal saline. The average aerosol-treatment time was 24, 12, and 16 min in groups A, B, and C, respectively. Changes in heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and rate pressure product (RPP) were analyzed by analysis of variance (ANOVA). In group A, tracheal intubation did not cause significant HD changes. In group B, a significant increase was observed in each HD parameter which, when compared with control, was less severe. Lidocaine toxicity, regurgitation, nausea, vomiting, or aspiration did not occur in any patient. Patients accepted the procedure well. This study found efficacy of the technique to be related to duration of aerosol treatment.     

Transport of fluid and macromolecules in tumors. IV. A microscopic model of the perivascular distribution

The therapeutic efficacy of various genetically engineered macromolecules is determined by their delivery and distribution in tumors. We have recently developed mathematical models which describe the interstitial velocity, pressure, and concentration profiles of macromolecules over the length scale of a solid tumor (Baxter and Jain, Microvas. Res. 1989, 1990, 1991). Nonspecific and specific antibodies and antibody fragments were chosen as typical macromolecules. The focus of the present investigation was microscopic transport, i.e., the distribution of pressure and solutes around individual blood vessels. Analytical solutions were obtained for interstitial velocities and pressures, while the concentration profiles were calculated numerically using the finite element method. The microscopic model describes flow patterns around an individual blood vessel in an infinite medium and concentration profiles around a single blood vessel in a network of capillaries. Our analysis is novel in that it incorporates interstitial convection, asymmetric filtration, and transcapillary convection to describe interstitial transport in tumors. The purpose of this model was to determine the effect of extravascular binding and interstitial convection on the distribution of macromolecules on a microscopic scale and to test the continuum hypothesis assumed in our previously published macroscopic models. An approximate one-dimensional model was compared with a more accurate two-dimensional model. The results of our microscopic model confirm that the continuum hypothesis used in our previous macroscopic model is reasonable. On a microscopic length scale diffusion is dominant, and short range distortions in the flow field do not significantly affect the penetration of macromolecules into the tissue. In addition, our model confirms the results of Fujimori et al. (Cancer Res., 1989) concerning a "binding site barrier." The implications of our results for cancer therapy are also discussed.     

Studies on the colour-change mechanism in a fresh-water teleost,Nandus nandus (Ham.) I. Neural control

Summary The existence and nature of chromatic fibres controlling the colour-change mechanism in the teleost,Nandus nandus has been studied by means of spinal sectioning at various vertebral levels of the animal between vertebrae 3 to 10. Spinal sectioning at or anterior to 5th vertebra completely eliminated the neural control of colour-change. As a result, the animal darkened to its maximum and the neural responses of different backgrounds were abolished. Spinal sectioning at or posterior to vertebra 6 did not affect the melanophores and at the same time did not interfere with the normal background responses of the animal. This study clearly shows that the chromatic fibres in this species run in the spinal cord and leave the latter at 5/6th vertebral level.Effect of adrenaline in the chromatic spinal-sectioned fish shows that the fibres innervating the melanophores are aggregating in nature and adrenergic in character. The results also suggest that the dispersed condition of pigment in the melanophores represents the resting state of the melanophores when they are under no stimulation.     

Subcommissural organ-Reissner's fiber complex of the teleost Clarias batrachus responds to GABA treatment

Subcommissural organ (SCO) is a highly specialized ependymal gland located in the roof of the third ventricle. The secretory products of the SCO, which condense to form Reissner's fiber (RF), were recently found to cross-react with the anti-calcitonin antibody. To understand the mechanisms regulating the formation of the RF and the possible function of these discrete structures, we studied the response of the SCO-RF complex to intracranially administered GABA, using immunocytochemical labeling with anti-calcitonin antibody. Although the SCO-RF complex of control fish was intensely immunostained, 1 h after GABA treatment, the ependymal cells revealed partial loss of immunoreactivity; the RF showed occasional loss of immunoreactivity with its diameter increased by about 56% of the control value. Following 2 h of GABA treatment, the SCO revealed dramatic loss of calcitonin-like immunoreactivity from the ependymal cells. The RF showed a dual response in this group, while in some segments the RF appeared conspicuously thick, elsewhere it appeared thin. The mean diameter was, however, not significantly different from the normal. Following 4 h of GABA treatment, while calcitonin-like immunoreactive material made its reappearance in the SCO, the RF diameter was uniformly reduced to about 35% of the control value. The responses by the RF as well as the SCO to intracranially administered GABA were blocked by pretreatment with bicuculline, a GABA(A) receptor antagonist. The results suggest that GABA, acting via GABA(A) receptors, may trigger the release of secretory material from the SCO and induce histomorphological changes in the RF indicative of discharge of stored material.     

Limb amputation on renal replacement therapy

Ten (10) diabetic and 7 non-diabetic patients on renal replacement therapy have undergone limb amputation in the authors' unit in the 1988 to 1996 period. The article examines the course of illness and survival patterns in this distinct and increasing sub-set in the amputee population. Rehabilitation and survival were significantly better in the diabetic group and it is recommended that it would be helpful for both prognosis and analysis if the sub-set of amputees on treatment for chronic renal failure is further divided into diabetic and non-diabetic sub-sets.     

Evaluation of osteopontin as biomarker for pancreatic adenocarcinoma.

OBJECTIVES: Pancreatic adenocarcinoma is a deadly disease with an overall 5-year patient survival of less than 5%. This dismal prognosis of pancreatic cancer is largely due to the advanced stage of the disease at presentation. If pancreatic cancer could be diagnosed more readily and accurately using serum markers, patient survival could theoretically be improved by enabling more patients to avail of surgical resection. One candidate tumor marker recently identified by global gene expression analysis of pancreatic cancer is the secreted glycophosphoprotein osteopontin (OPN). In this study, we evaluate OPN as a serum marker of pancreatic adenocarcinoma. METHODS: In situ hybridization for OPN was performed on a pancreatic adenocarcinoma tissue microarray. Serum OPN levels were determined in preoperative sera from 50 patients with pancreatic cancer and 22 healthy control individuals by competitive ELISA. RESULTS: In situ hybridization for OPN performed on a tissue microarray revealed strong OPN mRNA signal in tumor-infiltrating macrophages in 8 of 14 pancreatic adenocarcinomas. In contrast, OPN expression was not seen in the pancreatic cancer cells themselves, nor was it seen in normal pancreatic tissue or in the macrophages distant from the infiltrating cancer. Serum OPN levels, as measured by ELISA, were elevated in the sera of 50 patients with resectable pancreatic adenocarcinoma compared to 22 healthy control individuals (mean +/- SD for OPN was 482 +/- 170 ng/ml and 204 +/- 65 ng/ml, respectively; P < 0.001). Using a cutoff level of 2 SD above the mean for healthy individuals, elevated OPN had sensitivity of 80% and specificity of 97% for pancreatic cancer. In contrast, only 62% of these patients with resectable pancreatic cancer had elevated CA19-9. CONCLUSIONS: Serum OPN may have utility as a diagnostic marker in patients with pancreatic cancer.     

Tumours of the parapharyngeal space

A series of 14 parapharyngeal tumours has been studied with regard to their symptology, pre-operative evaluation and surgical management. High resolution computed tomography is now the best initial diagnostic study because it helps to determine the size and extent of the tumour, differentiate tumours of parotid and extraparotid origin, demonstrate degree of tumour vascularity, separate benign from malignant lesions, plan the surgical approach and predict prognosis.     

Management of jugular paragangliomas: the Gruppo Otologico experience.

OBJECTIVE: The objective of this study was to review the outcome of surgical management in patients of jugular paragangliomas. STUDY DESIGN: We conducted a retrospective case review. SETTING: Tertiary care otology and skull base center. MATERIALS AND METHODS: Fifty-five patients with the diagnosis of a jugular paraganglioma (Fisch Class C and D Glomus Jugulare) were managed over a period of 15 years. All patients with adequate follow up and complete records (53 cases) were reviewed with emphasis on the results of surgical management and the factors influencing them. INTERVENTION: All 53 patients were managed with a view to surgically extirpate the tumor. The primary approach was the infratemporal fossa approach-Type A used in the majority of the patients. In eight cases, the procedure was staged owing to the presence of large intracranial extension. Three patients required additional procedures to ameliorate the after-effects of lower cranial nerve resection. RESULTS: Gross total tumor removal was achieved in 49 patients. There were five cases of recurrence. Coupled with the residual tumors in five patients, the surgical control achieved was 83%. There was no perioperative mortality. There were two cases of postoperative cerebrospinal fluid leak, both of which required surgical exploration and closure. The facial nerve was resected in seven patients. The overall preservation rate of clinically uninvolved lower cranial nerves was 75%. CONCLUSIONS: The low level of complications along with a high surgical control achieved makes surgery the primary mode of treatment in the vast majority of these tumors, regardless of the size and location.