Effects of risk-associated human dietary macrocomponents on processes related to carcinogenesis in human-flora-associated (HFA) rats

Dietary fat, beef protein and fibre have been shown to modulatecancer risk in humans and the present study examined the biologicaleffects in human-flora-associated (HFA) rats of altering intakelevels within the normal human range. Two control groups, oneHFA and the other germfree (GF), consumed a human diet low infat, fibre and beef for 4 weeks; three other groups consumedhuman diets similar except for independent 3-fold increasesin fat, beef protein or fibre. After 2 weeks on the diets, magneticallyrecoverable microcapsules were given orally to the rats andsubsequently recovered from the faeces to assess endogenouscross-linking agents. After 4 weeks, measurements were madeof gut microfloral enzyme activities, hepatic activation ofdietary mutagens and hepatic DNA adducts by ³²P-postlabelling.Activation in vitro of the dietary mutagens 2-amino-3-methyl-3H-imidazo[4,5-f]quinolline (IQ) and 2-amino-l-methyl-6- phenytimidazo[4,5-b]pyridine(PhIP) by hepatic S9, formation of endogenous hepatic DNA adductsin vivo and the ß-glucuronidase activity of caecalcontents were all increased in the sequence high fat > highfibre > high beef = control. Of the two DNA adducts foundin all HFA rats, only one was present in GF controls, indicatingthat the human gut microflora (subject to human dietary modulation)either releases a DNA-adducting product able to act outsidethe gastrointestinal tract, or stimulates the generation ofsuch a product by mammalian processes. Caecal nitrate reductaseactivity was highest in rats fed the high beef diet, whilstentrapment of cross-linking agents was highest in those fedthe high fibre diet. These results show that risk-related componentsof human diets interact with human gut microflora to modulatethe production of endogenous DNA-adducting and cross-linkingsubstances.     

Hypothalamic-hypophyseal-testicular abnormalities and erectile dysfunction

Forty-five men presenting with erectile dysfunction were evaluated through history and nocturnal penile tumescence, Doppler, and EMG studies. Fifteen were classified as having organic and 30 as having psychogenic impotence. Three men had mild hypergonadotropism with low testosterone levels. One had hyperprolactinemia. No case of hypogonadotropic hypogonadism was detected. Six patients who had psychogenic impotence had low levels of testosterone.     

Prevention of laryngeal stenosis in Co2 laser management of recurrent respiratory papillomatosis

Laryngeal stenosis is one of the common complications in the management of recurrent respiratory papillomatosis. The authors have compared the results with regard to development of laryngeal stenosis, when surgical treatment was given with CO₂ laser alone in the early 34 cases plus 7 advanced cases, while in the remaining 13 advanced cases the CO₂ laser ablation was combined with the conventional cup forceps removal. Age, extent of disease, duration of the procedure and interval between two procedures were also noted. The incidence of laryngeal stenosis was found to be reduced in advanced cases when CO₂ laser was combined with the conventional cup forceps removal.     

A human immunodeficiency virus-resistant airway for cardiopulmonary resuscitation.

Due to fear of transmitted disease, mouth-to-mouth cardiopulmonary resuscitation (CPR) is now rare, even though early CPR is associated with a fivefold to 30-fold increase in survival. The authors have devised a one-piece silicone mask (Kiss of Life [KOL], Brunswick Biomedical Technologies, Inc, Warehom, MA) with a one-way valve and circular recess to form a no-contact lip seal, enabling mouth-to-mouth CPR to be given. The ventilatory volume during mannequin CPR using the KOL mask was 0.75 +/- 0.235 L. This volume was significantly (P less than .05) greater than that generated by alternate widely used airways (range, 0.195 +/- 0.147 to 0.617 +/- 0.208 L). To assess mask performance in vivo, the authors measured exhaled volumes in 10 apneic anesthetized patients under three conditions: with the KOL mask, a standard anesthetic mask and bag, and an anesthetic mask with an endotracheal tube. The results were: anesthetic mask and tube, 1.5 L (range, 1.2 to 1.7 L); KOL mask, 1.1 L (range, 1.0 to 1.3 L); anesthetic mask alone, 0.7 L (range, 0.5 to 0.8 L). To test permeability, we exposed two KOL masks to a high titer of human immunodeficiency virus (HIV)-1 soup (10(6) culture infection doses/mL) for 10 and eight masks for 60 minutes, respectively, and cultured swabs of the interior of the valve for 1 month. There was no growth in any culture. These data suggest that the KOL mask has excellent ventilating characteristics, is practical (pocket-portable, disposable), experimentally impermeable to HIV-1, and inexpensive.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cervical Anterior Spinal Cord Infarction

Spinal cord infarction or ischemia predominates in the thoracic region, less so in the cervical and lumbar regions. Different etiological factors have been implicated in anterior spinal artery syndrome. Magnetic resonance imaging (MRI) allows in vivo imaging of spinal cord disease, including infarction. A 31-yearold, previously healthy man had an acute onset of interscapular pain, followed by rapid development of quadriparesis associated with paresthesias and mild bladder dysfunction. Initial MRI of the cervicothoracic region demonstrated normal findings. A repeat study obtained 6 days later showed marked increase in the cervical cord size, especially at the C6-7 level. On the T2-weighted sagittal series and after gadolinium injection, increased signal in the anterior portions of the cord extending from C-4 to the T2-3 interspace was noted. This was most prominent at the C-6 and C-7 levels. The coronal views revealed abnormal high signal in the region of the anterior horns of the gray matter, a finding that is recognized as an “owl's eyes” pattern. Because the MRI changes of cerebral infarction may succeed a clinical event by hours or days, accurate diagnosis may require delayed or repeated studies. This report suggests that the diagnosis of spinal cord disease requires a similar evaluation.     

Three balanced anesthetic techniques for neuroanesthesia: infusion of thiopental sodium with sufentanil or fentanyl compared with inhalation of isoflurane.

STUDY OBJECTIVE: To compare emergence from anesthesia and the hemodynamic and respiratory depressant effects of thiopental sodium infusion plus sufentanil or fentanyl with those of isoflurane as the primary component of a balanced technique for neuroanesthesia. DESIGN: Randomized, double-blind, prospective study. SETTING: University hospital and its affiliated Veterans Affairs Medical Center. PATIENTS: Thirty patients undergoing elective craniotomy for aneurysm or tumor. INTERVENTIONS: Thiopental with infusion of sufentanil 0.1 microgram/kg/hr, thiopental with infusion of fentanyl 1 microgram/kg/hr, or inhalation of 0.25% to 2% isoflurane as the major component of a balanced anesthesia technique that included nitrous oxide (N2O) and vecuronium (potency ratio of sufentanil to fentanyl, 10:1). MEASUREMENTS AND MAIN RESULTS: Intraoperative stress response (as indicated by intraoperative hypertension) was said to be the percentage of time the patient required administration of an antihypertensive drug, measuring from the first dose of thiopental to discontinuation of N2O at the end of the procedure, excluding any period of induced hypotension. Rapidity of emergence was measured by the number of minutes from discontinuation of N2O to first opening of the eyes on command. Adequacy of spontaneous ventilation was evaluated by determining partial pressure of arterial carbon dioxide 1, 2, and 3 hours after discontinuation of N2O. Extent of vasoactive drug administration for control of intraoperative hypertension (as determined by the clinicians caring for the patients) was described by minutes of vasodilator infusion and milligrams of propranolol or labetalol administered. The frequency of postoperative hypertension was defined as the number of patients in each group who required medication for postoperative hypertension. No significant differences in variables were found for thiopental/sufentanil, thiopental/fentanyl, or isoflurane when these drugs were used with N2O and vecuronium. CONCLUSIONS: Any one of these balanced anesthetic techniques appears appropriate for craniotomy.     

The indications for elective treatment of the neck in cancer of the major salivary glands.

To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group.     

Factors affecting patency of internal thoracic artery graft: clinical and angiographic study in 1434 symptomatic patients operated between 1982 and 2002.

OBJECTIVE: The purpose is to define factors influencing long-term patency of the internal thoracic artery (ITA) to optimize the operative strategy. METHODS: 1482 left internal thoracic artery (LITA) and 636 right internal thoracic artery (RITA) symptom-directed angiograms were studied in 1434 patients. Data were prospectively collected from patients who had primary coronary artery bypass surgery during the period 1982-2002. The mean age of patients was 59 years; 85% were male. The mean period from operation to re-angiogram was 80 months. LITA was grafted to left anterior descending coronary artery (LAD) in 82% of cases, RITA to right coronary artery (RCA) in 40% and circumflex artery in 35% of cases. Graft failure was defined as > or =80% stenosis. RESULTS: 96.3% of LITA and 88.1% of RITA grafts were patent. No patient variables were significantly associated with graft patency (age, gender, diabetes, hypertension, LVEF, NYHA, AMI). Target coronary artery was associated with patency of both LITA and RITA grafts with maximum patency when grafted to LAD (P = 0.02) RITA had the worst patency to RCA, patency for the left system was identical to LITA. Proximal anastomosis to aorta (free RITA) had significantly better patency when compared with in situ RITA to RCA system (P = 0.005) while similar patency when grafted to left system. ITA diameter and target artery diameter were not associated with graft patency. Recent operations had better RITA patency (P = 0.03). The interval from operation to angiogram was not associated with ITA patency (96% patency for LITA and 88% patency for RITA, remained stable when studied at <1, 1-4, 5-9, 10-14 and >15 years). CONCLUSIONS: Even in a patient cohort that had adverse symptoms, excellent LITA and RITA patency was achieved which almost remained constant through all time intervals studied.