Basic surgical techniques and variations of endoscopic sinus surgery

This article gives complete information on the care of the endoscopic sinus surgery patient. Indications and preoperative evaluations necessary for endoscopic sinus surgery are described. The technique of functional endoscopic sinus surgery is covered in detail. Postoperative care and complications are also described. Various procedures for patients with extensive or unusual disease are discussed.     

Neuropeptide modulation of muscarinic receptors and function in cerebral cortex of young and senescent rats.

The possible influence of several neuropeptides on muscarinic receptor binding and function in fronto-parietal cortex of young and senescent Fischer 344 rats was examined. Low concentrations (100 nM) of cholecystokinin, neurotensin and vasoactive intestinal polypeptide (VIP), added in vitro, enhanced carbachol-stimulated phosphoinositide metabolism in cortical miniprisms from both young and senescent rats, while somatostatin was ineffective. Interestingly, the VIP receptor antagonist [d-parachloro-Phe6,Leu17[VIP shifted the dose-response curve for carbachol significantly to the right, indicating inhibition of phosphoinositide hydrolysis. No direct actions of neuropeptides on the number or affinity of [3H]l-quinuclidinyl benzilate binding sites nor on agonist conformation states of the muscarinic receptor were noted in cortex from young animals. The neuropeptide modulation of phosphoinositide metabolism was selective for muscarinic systems, as norepinephrine-stimulated phosphoinositide hydrolysis was not altered. Pretreatment with hemicholinium-3, an inhibitor of high-affinity choline uptake, did not prevent the neuropeptide effects, indicating the interaction was probably postsynaptic. It is possible that pharmacologic manipulation of peptidergic processes could improve cholinergic neurotransmission in brain.     

Effects of training in use of executive strategies on a verbal memory problem resulting from closed head injury

This case study reports attempts to improve the recall performance of an adolescent (GC) who had suffered a closed-head injury. GC had a very limited range of ways of processing both spoken and written information and showed significant recall problems. Initial training in the use of strategies for list learning resulted in improvement in paired-associate recall but showed that initiation and use of the newly learned strategies would not occur without prompting. Executive strategy training was provided to improve GC's ability to identify a memory problem and to initiate a general plan for dealing with that problem. This training involved consideration of task analysis, strategy selection and initiation, and monitoring of strategy use. Evidence of long-term maintenance of improvement in level of recall on both paired-associate and free recall tests was noted following the executive strategy training.     

Peribursal fat plane of the shoulder: anatomic study and clinical experience

A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.     

Pulmonary infiltrates associated with noncytotoxic drugs

A wide variety of noncytotoxic drugs, including antibiotics, analgesics, narcotics, and psychotrophic and cardiovascular agents, may cause lung injury accompanied by roentgenographic infiltrates. The clinical manifestations of drug-induced lung disease are protean. Patients may present with acute injury resembling the adult respiratory distress syndrome, which must initially be distinguished from bacterial sepsis. Other drug-associated lung injury is characterized by a more subacute pneumonitis similar to an atypical infectious pneumonia. Finally, some drugs may cause insidiously progressive pulmonary infiltrates that share features with granulomatous infections. The more common drug reactions are discussed in this review, and, although the features of drug-induced lung disease are often relatively nonspecific, those features that either mimic infectious causes or may be helpful in differentiating these processes from infections are given particular emphasis.     

Intraperitoneal mesotheliomas induced in mice by a polycyclic aromatic hydrocarbon

Female mice of 6 strains (C3H/HeN, BALB/c, C57BL/6N, DBA/2, NIH Swiss, and AKR/N) were given the polycyclic aromatic hydrocarbon carcinogen 3-methylcholanthrene (MC) intragastrically in olive oil at a dose of 20 mg/kg, weekly for 12 wk. Half were pretreated 24 h before each MC administration with intraperitoneal beta-naphthoflavone (beta-NF, 150 mg/kg in olive oil), a noncarcinogenic inducer of certain cytochrome P-450 isozymes. Remaining mice were given olive oil prior to MC in the same fashion, or beta-NF in olive oil or olive oil alone without subsequent exposure to MC. All mice were killed when moribund or 13 mo after the start of treatment. Most of the mice, irrespective of treatment, exhibited signs of peritoneal injury, including inflammation, necrosis, granuloma formation, and mineralization. Mice of some of the strains also presented peritoneal mesotheliomas, in addition to a variety of other tumors. The incidence of unequivocal mesothelioma-bearing mice was 12/31 C3H/He and 9/32 BALB/c mice given only MC. Incidence was low in C57BL/6 (1/31) and DBA/2 (1/26), and no definite mesotheliomas were found in Swiss or AKR mice. There were in addition a number of cases of sarcoma (nine total in all strains) and of peritonitis (four total) that resembled mesothelioma to some degree and were initially diagnosed as much. beta-NF pretreatment reduced the frequency of mesotheliomas: there was only one definite mesothelioma in any of the beta-NF-MC groups, in a C3H/He mouse. Most of the mesotheliomas were mixed fibro-mesothelial type, sometimes with papillary epithelial excrescences. They typically grew in a botryoid pattern within the peritoneal cavity, coating the abdominal organs and sometimes actively invading these organs and the diaphragm. Some lesions exhibited pleomorphism, prominent giant cells, and frequent mitoses. In addition, several lesions consisting of severe mesothelial hyperplasia associated with tissue necrosis and inflammation were considered as possible early stages of mesothelioma development. It was postulated that peritoneal injury imposed by repeated intraperitoneal injection of oil acted as an enhancing factor for mesothelioma induction by MC. The pertinence of such a relationship to mechanisms in the etiology of human mesotheliomas is discussed.     

A markedly diminished pleiotropic response to phenobarbital and structurally-related xenobiotics in Zucker rats in comparison with F344/NCr or DA rats.

Phenobarbital (PB) and certain structurally-related compounds induce a variety of hepatic drug-metabolizing enzymes in many strains of rats. Thus, following administration of PB (300, 500 ppm), barbital (BB, 1500 ppm) or 5-ethyl-5-phenylhydantoin (EPH, 500 ppm), CYP2B1-mediated benzyloxyresorufin O-dealkylase activity and epoxide hydrolase activity were profoundly induced in female DA and F344/NCr rats. In contrast, outbred female lean and obese Zucker rats showed markedly reduced CYP2B1 responses (less than 15% and less than 5% of those observed in the female DA or F344/NCr rat) to PB (doses less than or equal to 300 ppm), BB (1500 ppm) or EPH (500 ppm). In parallel studies, profound increases in RNA levels coding for CYP2B1, glutathione S-transferases Ya/Yc (alpha subclass), or epoxide hydrolase were detected in the female F344/NCr rat following treatment with PB (300 ppm), BB (1500 ppm) or EPH (500 ppm). In contrast, lean Zucker rats showed a strong response only to the highest dose of PB (500 ppm), implying that the diminished response in the Zucker rats may occur at some pretranslational level. Similar studies with lower doses of PB, EPH or BB in male lean Zucker rats showed a decreased response, relative to that in male F344/NCr rats. However, this insensitivity was not as profound as that observed in the female Zucker rats. In fact, the response to PB-type inducers in male or female Zucker rats is probably most clearly explained as a shift of the dose-response curve sharply to the right (decreased responsiveness, compared to F344/NCr or DA rats of the same sex). This decreased responsiveness of female lean Zucker rats to induction of CYP2B1, relative to that of F344/NCr rats, was also observed with the structurally-diverse PB-type inducers clonazepam, clotrimazole and 2-hexanone. In contrast, the female Zucker rat (obese or lean) displayed a pronounced response to induction of CYP1A-mediated ethoxyresorufin O-deethylase activity by beta-naphthoflavone, a prototype inducer of CYP1A1 and CYP1A2. The Zucker rat would thus appear to represent a potentially exploitable genetic model for examining the mechanism of enzyme induction by the myriad xenobiotics which induce a PB-type response.