Search

The contribution of T-cell-receptor beta-chain diversity to the T-cell antigen-specific repertoire was investigated using single-chain T-cell-receptor transgenic mice. Animals that express the rearranged beta-chain gene from a T hybridoma with specificity for a hen egg lysozyme peptide, designated HEL (85-96) were analysed for their ability to respond to a panel of diverse antigens. Transgenic mice exhibited a significantly elevated response to HEL (85-96) which was shown to be due to an increased frequency of HEL (85-96)-specific T-cell progenitors. This increased frequency of specific progenitors resulted in the ability of transgenic mice to respond to the peptide in the absence of antigen priming. Conversely, transgenic mice failed to respond to any other antigen tested. Furthermore, this apparent deficiency was associated with a significant decrease in the frequency of antigen-specific T-cell progenitors in transgenic mice. Surprisingly, the ability to launch an alloresponse was unaffected by the exclusive expression of the transgene-derived beta-chain. These results indicate that beta-chain diversity is crucial for the ability of the T-cell population to elicit a rapid and robust response to the profusion of different antigen/major histocompatibility complex (MHC) ligands potentially encountered by an individual. Furthermore, these results suggest a lesser role for beta-chain diversity in contributing to allorecognition, and support a model in which the direct recognition of peptide-mediated conformational MHC forms is the major contributor to the alloreactive response exhibited by the majority of T cells.

Undetected lower-extremity deep-vein thrombosis (LEDVT) in the trauma patient can lead to significant morbidity and mortality. The purpose of this study was to: 1) evaluate the role of ultrasonography in the early detection of LEDVT in high-risk trauma patients; 2) identify prognostic indicators that predict LEDVT; and 3) evaluate the efficacy of selected inferior vena cava (IVC) filter placement in the prevention of pulmonary emboli. From October 1993 through December 1994, all adult multiple-trauma patients admitted to the Trauma Service who required prolonged bed rest (>3 days) or sustained a lower-extremity, pelvic, or spinal fracture with paralysis were prospectively studied with serial physical examinations and lower-extremity venous ultrasounds within 72 hours of admission and then weekly until discharge. Two hundred twenty-eight patients were entered into the study. Thirty-nine patients (17%) developed ultrasound evidence of LEDVT; of these, only seven (18%) were evident on physical examination. This allowed 32 patients (82%) with unsuspected LEDVT to receive earlier definitive therapy. Multivariate logistic regression analysis of LEDVT with various predictors found age, hospital length of stay, and lower-extremity trauma to be significant predictors of LEDVT (P < 0.05). Twenty-nine patients (74%) had immediate IVC filter placement upon ultrasound identification of proximal LEDVT. None of these patients developed pulmonary emboli. Ten patients (26%) with a LEDVT were treated with systemic anticoagulation alone. One of these patients sustained a fatal pulmonary embolus. In a historic control group of 234 high-risk trauma patients admitted in the 14 months prior to implementing screening ultrasounds, six patients sustained pulmonary emboli (P < 0.05). Screening ultrasounds combined with selective placement of IVC filters play an important role in reducing the morbidity and mortality associated with LEDVT in high-risk trauma patients.

The purpose of this review is to investigate the utility of autotransfusion in trauma patients in the past 3 years. A retrospective review was conducted of the charts for whom the Haemonetics Cell Saver autotransfusion device (Haemonetics Corp., Natick, MA) was utilized between January 1, 1993, and December 31, 1995. The estimated blood loss and quantity of blood transfused were noted for abdominal trauma patients. Costs of autotransfusion were then compared to estimated blood bank costs for this group. The Haemonetics Cell Saver autotransfusion device was requested for 592 cases from January 1, 1993, to December 31, 1995. Nonorthopedic trauma cases comprised 25 per cent of all autotransfusion cases. One hundred twenty-six patients had isolated abdominal trauma and had a mean estimated blood loss of 4864 +/- 6070 cc. The average volume of intraoperatively salvaged autologous blood transfused (autotransfusion) per patient was 1547 +/- 2359 cc, or a bank blood equivalent of 6.9 units of packed red blood cells. The total cost of autotransfusion in these patients was $63,252.00. Had bank blood been used instead of salvaged autologous blood, the cost would have been $114,523.00; thus, autotransfusion resulted in a savings of $51,271.00. The use of salvaged autologous blood comprised 45 per cent of total blood transfused. On a case-by-case basis, 75 per cent of cases were cost-effective compared to blood bank costs for an equivalent transfusion. Transfusion of intraoperatively salvaged autologous blood (autotransfusion) is a cost-effective, efficient way to provide blood products to operative trauma patients.

Widespread application of mammography and breast ultrasound has led to improved recognition and delineation of breast lesions. Localization of these lesions with specialized, computerized stereotactic radiographic equipment or ultrasound imaging with subsequent use of this image to guide percutaneous core sampling of the abnormal area is less invasive, less painful, highly accurate, and less expensive than incisional breast biopsy with preoperative needle localization. These image-guided techniques have progressively matured in recent years, are used regularly by more and more surgeons, and are areas of clinical care and technology in which surgeons should be familiarized and educated.

The purpose of this study was to determine 1) the incidence and magnitude of elevation in admission serum amylase and lipase levels in extrapancreatic etiologies of acute abdominal pain, and 2) the test most closely associated with the diagnosis of acute pancreatitis. Serum amylase and lipase levels were obtained in 306 patients admitted for evaluation of acute abdominal pain. Patients were categorized by anatomic location of identified pathology. Logistic regression analysis was used to compare the enzyme levels between patient groups and to determine the correlation between elevation in serum amylase and lipase. Twenty-seven (13%) of 208 patients with an extrapancreatic etiology of acute abdominal pain demonstrated an elevated admission serum amylase level with a maximum value of 385 units (U)/L (normal range 30-110 U/L). Twenty-six (12.5%) of these 208 patients had an elevated admission serum lipase value with a maximum of 3685 U/L (normal range 5-208 U/L). Of 48 patients with abdominal pain resulting from acute pancreatitis, admission serum amylase ranged from 30 to 7680 U/L and lipase ranged from 5 to 90,654 U/L. Both serum amylase and lipase elevations were positively associated with a correct diagnosis of acute pancreatitis (P < 0.001) with diagnostic efficiencies of 91 and 94 per cent, respectively. A close correlation between elevation of admission serum amylase and lipase was observed (r = 0.87) in both extrapancreatic and pancreatic disease processes. Serum amylase and lipase levels may be elevated in nonpancreatic disease processes of the abdomen. Significant elevations (greater than three times upper limit of normal) in either enzyme are uncommon in these disorders. The strong correlation between elevations in the two serum enzymes in both pancreatic and extrapancreatic etiologies of abdominal pain makes them redundant measures. Serum lipase is a better test than serum amylase either to exclude or to support a diagnosis of acute pancreatitis.

Transgenic mouse technology has been used extensively to investigate biomedically important issues in such diverse areas as mammalian development, neurophysiology, and immunology. It has also been used to develop models for several disease states that have significant medical impact. The power of this technology, which allows for either the expression of genes of interest in defined tissues or the engineered loss of function for certain genes, offers great opportunity to enhance our understanding of the complex events that culminate in allergic contact dermatitis (ACD). Recently several lines of preexisting or newly generated transgenic mice have been employed in this task. However, the use of transgenic mice in the investigation of ACD is still in the early stages and, therefore, there are many as yet unexploited opportunities in this area. The purpose of this review is to describe how the results of recent experiments employing transgenic mice have impacted on our current understanding of ACD and to enumerate possible future opportunities for the use of transgenic mouse technology to further advance that understanding.

Minimally invasive diagnostic techniques in evaluating patients with breast disease have been increasingly utilized and accepted by physicians and patients over recent years. The incorporation of stereotactic core needle biopsy and ultrasound-guided core needle biopsy into the office practice of evaluating patients with breast disease by our surgical faculty has been met favorably. These procedures are readily learned by surgeons. The judicious use of these procedures is evidenced by the malignancy rate of core biopsies of 16 per cent, identical to the historical rate for needle localization assisted excisional biopsy at our institution. Core breast biopsy expedites definitive diagnosis and optimizes patient convenience. Reimbursement is highly variable, and active physician participation in negotiating with payors to insure that costs are met is essential.

Mechanical ventilatory support requiring tracheal intubation may be necessary for variable lengths of time in injured patients. Criteria useful in predicting the need for prolonged tracheal intubation has not been clearly established in the trauma population. Early identification of patients requiring prolonged tracheal intubation and mechanical ventilatory support could lead to earlier tracheostomy and subsequent reductions in complications associated with prolonged endotracheal intubation. This study evaluated the ability of clinical measures of injury severity, mental status, oxygenation, and ventilation to predict the need for prolonged mechanical ventilatory support (> or = 14 days) early in the postinjury course of the adult trauma patient requiring endotracheal intubation and mechanical ventilatory support within the first 24 hours of injury. All adult trauma patients admitted to our Level I trauma center over a 4-year period between January 1990-December 1993 were evaluated. A total of 212 patients met study criteria that included intubation within the first 24 hours of injury, ventilatory support requirement > or = 72 hours, and a survival time of at least 14 days postinjury. Data pertaining to measures of injury severity (RTS, AIS, ISS), mental status (GCS), oxygenation [(A-a)O2], and ventilation (VE,EDC) were recorded for postinjury Day 1 and Day 5. There were 157 males and 55 females (age range of 16-91 years, mean 39.5 years). Mechanism of injury was blunt in 198 and penetrating in 14 patients. One hundred patients required prolonged mechanical ventilatory support. Data were analyzed by stepwise logistic regression analysis. Age and GCS values on Day 1 predicted the need for long term mechanical ventilatory support in a select group of patients, age 20 and GCS of 3 (P < 0.05). At Day 5, age, GCS, and (A-a)O2 gradient were predictive of the need for prolonged mechanical ventilatory support (P < 0.05). On Day 5, GCS of 3 predicted the need for long-term mechanic al ventilatory support regardless of age or (A-a)O2 gradient. GCS < or = 5 and (A-a)O2 > or = 150 predicted prolonged mechanical ventilatory support in young patients (age 20). At ages of 40 to 60, GCS < or = 7 and (A-a)O2 > or = 150 indicated the need for long term mechanical ventilatory support. In older patients (age > or = 80), GCS < or = 7 and (A-a)O2 gradient > or = 100 were predictive of long-term mechanical ventilatory support. Appropriate use of these clinical indicators may assist in early identification of patients requiring prolonged mechanical ventilatory support, and subsequent conversion from endotracheal intubation to tracheostomy with anticipated reduction in complications.

Temporary closure of abdominal surgical wounds is occasionally required when conditions of the abdominal wall or peritoneal cavity prevent closure or when early re-exploration is planned. The optimal temporary closure should contain and protect the contents of the peritoneal cavity from external contamination and injury; preserve the integrity of the abdominal wall; be simple to perform and maintain; provide ease of reentry; and have minimal adverse physiologic effects. Based on these criteria, a method of temporary abdominal wound closure (termed the vacuum pack) has been designed and evaluated. The operative technique includes 1) placement of a fenestrated polyethylene sheet between the abdominal viscera and anterior parietal peritoneum; 2) placement of a moist, sterile laparotomy towel over the polyethylene sheet; 3) placement of two closed suction drains over the towel; 4) placement of an adhesive backed drape over the entire wound, including a wide margin of surrounding skin; and 5) suction applied to the drains, creating a vacuum and rigid compression of the layers of closure material. This creates a tight, external seal of the adhesive backed drape and facilitates drainage of the peritoneal cavity. From April 1992-December 1993, this temporary abdominal wound closure was performed 56 times in 28 patients, ages 6-78 years, for periods of 1-11 days. The procedure was used in 17 trauma patients and 11 non-trauma patients. Indications for use included increased intra-abdominal pressure in nine, mandatory re-exploration in 10, and a combination of these indications in nine patients. Pre- and postprocedural airway and systemic blood pressures were unaffected by this closure.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: To evaluate the effect of preoperative localization studies on the surgical management of patients with primary hyperparathyroid disease (PHPT)., Summary Background Data: Reported cure rates of initial surgical exploration for PHPT are close to 95%. Preoperative localization studies are frequently obtained to improve surgical success and decrease operative time., Methods: Initial cervical exploration was performed in 113 patients with PHPT from 1981 to 1993. Twenty-four patients (21%) had surgery without preoperative localization studies. The remaining 89 patients (79%) had 132 noninvasive preoperative localization studies. Success of the localization studies in tumor localization, pathologic findings, postoperative serum calcium levels, and operative times were compared. Patient costs of the studies were calculated., Results: Disease was identified during operation in 23 of 24 patients (96%) having cervical exploration without preoperative localization studies, and they had normal calcium levels after surgery. Eighty-seven of 89 patients (98%) having preoperative localization studies were surgically cured. The highest sensitivity rate (60%) and highest positive predictive value (79%) of the localization studies were found with thallium-technetium scintiscanning. Average cost of the localization studies was $901 per patient. Combination studies were obtained in 32 patients at an average cost of $1,314 per patient without improving sensitivity. Mean operating time did not differ for localized and nonlocalized patients., Conclusions: Preoperative localization studies did not improve parathyroid localization or cure rate and did not substantially shorten operating time in initial cervical exploration for PHPT. The economic burden of routine preoperative localization studies in these patients is not justified.

Breast cancer will affect approximately one woman in nine, and it is estimated that approximately one-third of the 500,000 new cases of cancer among American women in 1993 will be cancer of the breast. With no current method of prevention available, early detection of breast cancer by regular self and physician performed breast examination in conjunction with screening mammography is emphasized. The rate of breast cancer detection has accelerated due to the ability of mammography to identify nonpalpable breast lesions. From January 1987 to January 1992, 1,323 breast biopsies were performed at Erlanger Medical Center, with 559 of these biopsies performed on 541 patients, utilizing needle localization. Of the 559 biopsies, 92 were positive for malignancy (17%). The mean patient age at detection of malignant lesions was 55.2 years. The most common mammographic abnormality leading to biopsy was an irregular breast tissue matrix (mass or density) with 25/191 (13%) biopsies positive for malignancy. The mammographic abnormality associated with the highest malignancy rate was the presence of calcifications in association with a mass or density 16/56 (29%). The upper outer quadrant (UOQ) was the most common site of biopsy 313/559 (56.0%), and biopsies from this region had the highest incidence of malignancy 67/313 (21%). Eighty-seven of the 92 patients with biopsy-proven malignancy underwent subsequent definitive surgical treatment. Tumor size did not correlate with node negative status, but evidence of microscopic invasion did. Preinvasive (in-situ) lesions were present in 23/92 biopsies (25%). There was no axillary involvement associated with in-situ carcinomas.

Laparoscopic cholecystectomy has emerged as the treatment of choice for uncomplicated cholelithiasis. Despite early concerns, many surgeons have applied this new technique to more complicated biliary tract disease states, including biliary pancreatitis. To evaluate the safety of laparoscopic cholecystectomy in this setting, we retrospectively reviewed 29 patients with clinical and laboratory evidence of biliary pancreatitis who underwent this procedure between March 1990 and December 1992. The severity of pancreatitis was determined by Ranson's criteria. Two patients had a Ranson's score of 6, one of 5, one of 4, five scored 3, nine scored 2, nine also scored 1, and two patients scored 0. The mean serum amylase level on admission was 1,610 (range 148 to 7680). All patients underwent laparoscopic cholecystectomy during the same hospital admission for biliary pancreatitis, with the mean time of operation being 5.5 days from admission. Operative time averaged 123 minutes (range 60-220 minutes). Intraoperative cholangiography was obtained in 76 per cent of patients. Three patients had choledocholithiasis on intraoperative cholangiography and were treated with choledochoscopy, laparoscopic common bile duct exploration, and saline flushing of the duct. The mean length of hospital stay was 11 days (range 5-32 days). There were seven postoperative complications requiring prolonged hospitalization with all but one treated non-operatively. One patient with a preoperative Ranson score of 6 developed necrotizing pancreatitis and subsequently required operative pancreatic debridement and drainage. There were no deaths in this series and no postoperative wound infections. The average recovery period for return to work was 2 weeks. These statistics compare favorably with literature reports for open cholecystectomy in biliary pancreatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Superior mesenteric artery injuries remain a challenge to even the most experienced trauma surgeon and continue to carry a significant mortality in spite of aggressive management. If possible, primary arteriorrhaphy should be performed, as mortality has been shown to increase with more complex methods of repair. This probably emphasizes the severity of the vascular injury and hemorrhagic complications rather than the complications of the repair itself.

Advances in laparoscopic technique have provided the opportunity to perform preperitoneal herniorrhaphy and potentially avoid the morbidity associated with open techniques. From January 1991 to May 1992, two primary surgeons repaired 63 inguinal hernias (42 indirect, 20 direct, 1 femoral) on 48 patients using a standardized laparoscopic technique. The hernia defect was visualized laparoscopically, and the peritoneum anterior to the defect was incised. The hernia sac was dissected from the inguinal canal. The hernia defect was then loosely packed with rolled 1 x 6-inch polypropylene mesh (average number of rolls used was 3.4). A sheet of polypropylene mesh (average 5 x 8 cm) was then placed over the mesh rolls and the hernia defect and anchored with an endostapler. The peritoneum was closed over the mesh sheet with standard laparoscopic clips. There were 44 males and 4 females in the study group. The mean age was 55 years (range, 17-89 years). The mean follow-up was 5.8 months (range, 1-12 months). Thirty-three patients underwent unilateral hernia repair, and 15 patients underwent bilateral hernia repair. Clinically unsuspected contralateral hernias were identified at the time of laparoscopy in seven patients. The mean duration of surgery was 118 minutes (range, 80-165 minutes) for bilateral hernia repair, and 70 minutes (range, 45-100 minutes) for unilateral hernia repair. All patients with laparoscopic hernia repairs were treated on a same-day or less-than-24-hour in-hospital stay. Complications were designated as minor, moderate, or severe. There were 14 minor complications, which included subcutaneous hematomas at the trocar site, scrotal ecchymosis, groin swelling emphysema, and testicular asymmetry.(ABSTRACT TRUNCATED AT 250 WORDS)

A simplified method of laparoscopic inguinal herniorrhaphy using prosthetic materials was evaluated in a swine hernia model. The goals of this study were to determine 1) effectiveness of repair in a rapidly growing animal, 2) effectiveness and extent of adhesion formation of different prosthetic materials, 3) the effect of repair on testicular growth, and 4) histologic effects on the hernia site and surrounding structures. In a prospective randomized study, 30 juvenile male swine (average, 23 kg) with 35 congenital indirect inguinal hernias underwent laparoscopic herniorrhaphy using one of three prosthetic materials: Group 1 (polytetrafluoroethylene/Gore-Tex), N = 10; Group 2 (polypropylene mesh/Marlex), N = 10; Group 3 (polypropylene mesh/Prolene), N = 10. A standardized laparoscopic herniorrhaphy technique consisting of stapling prosthetic material over the hernia defect without peritoneal dissection was employed. During the 3-month postoperative period, animals were sequentially examined for normal growth and development, normal testicular development, and signs of hernia recurrence. Clinically apparent complications related to herniorrhaphy occurred in five animals (17%) during the observation period (one with repair failure, one with testicular torsion, two with repair failure and bowel obstruction, and one with intestinal obstruction secondary to adhesions). All three animals with bowel obstruction died. At 90 days after surgery all remaining animals (N = 27) were euthanized (Group 1 = 9, Group 2 = 8, Group 3 = 10). Average weight was 84 kg. Necropsy findings included no additional hernia recurrences, and one mesh erosion into the urinary bladder.(ABSTRACT TRUNCATED AT 250 WORDS)

Laparoscopic cholecystectomy has become the procedure of choice in most hospitals for the resolution of surgically treatable gallbladder disease. Few reports address the results of laparoscopic cholecystectomy in comparison to open cholecystectomy during the same time interval within the same institution. One hundred ninety-six laparoscopic cholecystectomies were performed from April 1990 through February 1991. Initial patient selection was restricted to elective procedures for chronic cholecystitis with expanded indications as experience was gained. Of the 196 cases, 11 required conversion to open cholecystectomy, leaving 185 laparoscopic cholecystectomies for comparison. During the same period, 82 open cholecystectomies were performed. Thirty-nine of these were complicated cases and would not have been considered for laparoscopic cholecystectomy early in the study, leaving 43 routine open cholecystectomies for comparative purposes. In the laparoscopic group, 1.1 per cent of the patients had major operative complications as opposed to the open group, which had none. There were no common bile duct injuries in either group. To provide a true cost-benefit analysis, a group of patients was identified that would qualify for elective, same-day admission for either an open or laparoscopic procedure. Laparoscopic cholecystectomy (LC) was performed on 70 patients, and open cholecystectomy (OC) was performed on 26 patients. A comparison of data from these groups showed no significant difference in age or sex. Hospitalization costs averaged $5,390 for the LC group versus $5,392 for the OC group. Postoperative hospital stay averaged 1.3 days for the LC group versus 3.7 days for the OC group (P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: We describe a patient with primary Sjögren's syndrome who developed severe, acute, anterior uveitis (iritis), an uncommon complication in this setting., Methods: We present the case report of the clinical findings, course, treatment, and resolution of the acute uveitis. Titers of anti-SS-A/Ro and anti-SS-B/La antibodies were assessed (by immunodiffusion), as were fluorescent antinuclear antibodies (on HEp-2 cells) and cryoglobulins., Results: Initial treatment with topical steroids, oral prednisone (20 mg/day), and oral methotrexate was unsuccessful. The iritis resolved after combined treatment with intravenous cyclophosphamide (1,500 mg/month), high-dose prednisone (60 mg/day), and cyclosporine (5 mg/kg/day)., Conclusion: An uncommon, severe complication of primary Sjögren's syndrome is acute uveitis. Combination immunosuppressive therapy may be needed to control this condition.

Glaxo has practiced incineration of liquid and gaseous wastes for over twenty years and currently operate eleven liquid and gas incinerators in the United Kingdom and Singapore. The liquid incinerators burn, as their main streams, those solvents that cannot be recovered and recycled within the processes. The early installations were for readily combustible solvents only. However, there has been a progressive move into the destruction of more difficult and hazardous wastes, with the consequential requirements for more sophisticated technology, in the belief that the responsible destruction of waste should be tackled near to its source. The eventual aim is to be self-sufficient in this area of waste management. The incineration of hazardous liquid and gaseous waste has presented a series of design, operational and monitoring problems into account which have all been successfully overcome. The solutions take into account the environmental consequences of the operations from both liquid and gaseous emissions. In order to ensure minimal environmental impact and safe operation the best practicable technology is employed. Environmental assessment forms part of the process development and permitting procedures.

In severe traumatic injuries to the lower extremity, it is often a difficult decision to attempt heroic efforts aimed at limb salvage or to amputate primarily. To answer this question, the authors performed a 5-year review of 70 limbs in 67 patients. Patients were identified as presenting with major lower extremity trauma and an associated arterial injury. Nineteen (27%) of the 70 limbs were amputated. Limb salvage was not related to the presence or absence of shock and order of repair (orthopedic or vascular). No statistical difference was noted between the time of injury to operative repair in either the amputated or limb salvage group. Limb salvage was related to warm ischemia time and the quantitative degree of arterial, nerve, bone, muscle, skin, and venous injury. A limb salvage index (LSI) was formulated based on the degree of injury to these systems. All 51 patients with an LSI score of less than 6 had successful limb salvage (p less than 0.001). All 19 patients with an LSI score of 6 or greater had amputations (p less than 0.001). Although statistics cannot replace clinical judgment, this index can be a valuable objective tool in the evaluation of the patient with a severely traumatized extremity.

The macula lutea of 23 donors aged 90 to 101 years were examined by light and electron microscopy and compared to maculas from a 49- to 68-year-old age group. The number of foveal photoreceptors and retinal pigment epithelial cells, the presence of macular pigment, and lipofuscin fluorescence were assessed. Pathologic characteristics typical of age-related macular degeneration occurred in nine of the 90- to 101-year-old group with changes ranging from early neovascularization to fully developed disciform scars, geographic atrophy, and macular holes. Several retinas had pigment epithelial and photoreceptor cell numbers equal to those of the younger group, but most showed cell loss. Thickened, debris-filled Bruch's membrane and choriocapillary atrophy, although common, were not an invariable accompaniment to old age. Clinicians should advise elderly patients that their chances of maintaining macular structure, and hopefully function, are better than 50%.

Sinclair strain miniature swine spontaneously develop and regress malignant melanoma lesions, with uveitis and vitiligo occurring subsequent to tumor regression. Peripheral blood lymphocytes (PBL) of Sinclair swine undergoing tumor regression and melanocyte destruction demonstrated significant lytic activity against K562, porcine semiallogeneic uveal melanocytes, and melanoma cells in 4-h chromium release assays. The ability of porcine PBL to lyse these target cells appears to be an age-associated immune response, as evidenced by the relative inability of PBL of pigs less than 4 weeks old to lyse target cells. In young adult pigs, however, PBL cytotoxic activity significantly increases; piglets 6 weeks old and older demonstrate efficient killing of all three targets. Conjugate formation assays demonstrate that a lymphoid effector cell possessing large granular lymphocyte (LGL) morphology may be involved in melanocyte destruction. These findings suggest that a LGL subpopulation may participate in melanoma and melanocyte destruction which can induce a uveitic syndrome in Sinclair swine with melanoma.

We successfully treated two patients with severe Staphylococcus epidermidis blepharoconjunctivitis by means of a topical vancomycin hydrochloride solution (50 mg/ml) prepared with sterile water. Aqueous vancomycin preparations, however, cause significant ocular irritation probably because of low pH and osmolality values. Solutions prepared with normal saline (5 mg/ml) and phosphate-buffered artificial tears (5 mg/ml and 50 mg/ml) were significantly less irritating and possessed equivalent in vitro antimicrobial activity. Topical vancomycin should be used only when commercially available antibiotics are inadequate.

A new type of epidemic kerotoconjunctivitis, caused by adenovirus type 19, is currently present in this country. It can be spread by tonometry, but in this report, appeared to be more likely to be spread by finger to eye contact.

A light and electron microscopical study of subretinal fluid removed at surgery for rhegmatogenous retinal detachment showed a heterogeneity of cell types originating from the neural retina, pigment epithelium, and wandering cells of the blood. Subcellular organelles sedimenting in the centrifuged pellets could be identified as to cell of origin, health of the parent cell, and time since cell rupture. Acellular specimens were typical of angiomatous detachments or long-standing rhegmatogenous detachments. Because various mechanisms of cellular pathophysiology contribute to the destructive and reparative processes during retina detachment, the cytologic analysis of subretinal fluid becomes a useful tool in understanding the biological processes that affect visual recovery or impairment after successful retinal detachment surgery.

In a substrain of Sinclair miniature black swine, bred for increasing incidence of cutaneous malignant melanomas, tumor regression occurs spontaneously and is accompanied by depigmentation of the skin, hair, and eyes. We conducted a 12-month longitudinal study of the ocular phenomena in 30 swine beginning at 3 weeks of age. The clinically observed sequence of depigmentation of the fundus and iris was correlated with histopathologic changes in selected enucleated eyes. Normal melanocytes of the uveal tract are destroyed between the 4th and 16th week of life. Melanocyte destruction is preceded by an invasion of the uveal tract by mononuclear cells having the ultrastructural features of lymphocytes and monocytes. Melanin and other cellular debris of ruptured melanocytes are ingested by macrophages which then migrate to the walls of blood vessels. Cataracts and band keratopathy develop secondary to the uveitis in some animals. Pilot electroretinograms show diminished electrical activity in photoreceptors of totally depigmented eyes possibly indicating ischemic or toxic damage to the retina. The retinal pigment epithelium remains essentially normal during the acute stages of uveal inflammation; later some damage and reparative hyperplasia may occur. The death of normal uveal melanocytes that occurs during the systemic attack on the cutaneous malignant melanomas appears to be an "innocent bystander" error in the immune recognition mechanism. The antigenic basis of this immunologic cross reaction is under investigation.

A patient with hereditary crystalline corneal dystrophy of Schnyder required penetrating keratoplasty because of poor visual acuity. Blood cholesterol was labeled with 14C-cholesterol and 11 days later a penetrating keratoplasty was done. At the time of surgery, corneal levels of cholesterol were much higher than serum levels, showing that cornea is an active site for the uptake and storage of cholesterol in this disorder.

An animal model of malignant melanoma of the eye was established by transplanting a cell suspension from cutaneous melanomas into the anterior chamber of the eye in Sinclair Farm miniature swine. The frequency of tumor takes in the eye was increased from 8.9% to 22% by treating the animals simultaneously with subconjunctival triamcinolone acetonide. As an animal model for hematoporphyrin derivative--photoradiation treatment of human malignant melanoma of the eye, this does not appear to be a good research tool because of the sporadic incidence of tumor takes, the rapid growth of tumor within the eye causing glaucoma, and the dark iris pigmentation of successful tumor takes, which hides extensive underlying ciliary body tumor.

A strain of miniature Sinclair swine that have cutaneous malignant melanomas destroy their tumors via an immunologic process. Destruction of apparently normal melanocytes of the uveal tract occurs concurrently with tumor cell lysis. The authors investigated possible involvement of humoral antibodies in uveal melanocyte lysis. Uveal antigens solubilized by a variety of reagents were tested by immunodiffusion against autologous and homologous sera; no precipitation lines were found. Western blots of electrophoresed uveal proteins when tested against serum from an animal with a great tumor load showed no antigen-antibody reactions. No specific humoral antibodies were detected. Sera tested for immune complexes also were negative. Invasion of the uveal tract by mononuclear cells was quantified in 1-micron-thick sections of tissue taken at various stages of ocular depigmentation. Disappearance of melanocytes was preceded by an increase in mononuclear cells and followed by an increase in melanin-containing macrophages. The ultrastructural features of the invading cells are presented. The authors conclude that cell-mediated uveal melanocyte destruction is the most likely basis for the uveitis and other damaging sequelae.

Lenses of cataract-webbed (cw) Peromyscus maniculatus were examined by electron microscopy and compared to age-matched normal deer mouse lenses. Precataractous lenses of offspring of cw/cw matings were examined and compared to early cataract development in the opposite eye of the same animal. The earliest ultrastructural change leading to disturbance of lens transparency was cell fusion and formation of fiber cell syncytia in the posterior subcapsular region. Fiber cells lost their regular hexagonal packing. Small osmiophilic densities on the plasma membrane coincided with many of the sites of cell confluency. Larger osmiophilic whorls were usually localized in ball-and-socket interlocking junctions after the opacity spread. Epithelial cells from the nasal ventral equator migrated to the posterior pole. Later when underlying cortical fibers ruptured, the migrated cells phagocytized lens proteins and incorporated them in acid-phosphatase positive lysosomes. Fiber cells 3 to 20 layers deep in the cortex of normal and cataractous lenses had acid phosphatase reaction product coating the plasma membrane; the possible significance of this finding is discussed. We postulate that this hereditary cataract results from a defect in turnover and control of plasma membrane components.

Retrospective review of eight years' experience with the Mallory-Weiss syndrome emphatically supports the need for accurate, early localization of the site of upper gastrointestinal hemorrhage. Pertinent aspects of the history and physical and laboratory evaluation of this group of patients were analyzed to determine the relative merits of each in diagnosis and treatment. Angiography was helpful as a diagnostic aid in a small group of patients. Endoscopy, the cornerstone of diagnosis, is essential in the choice of the management program. Data from this study support the following conclusions: (1) patients not bleeding at the time of endoscopy rarely require surgical intervention; and (2) patients bleeding at the time of endoscopy vary as to their need for operative treatment and deserve a trial of preliminary medical therapy.

The data presented indicate that in experimental infections of the mouse cornea, toxin A of Pseudomonas aeruginosa contributes to the organism's pathogenicity, whereas active elastase may not be required. After traumatization, corneas were infected with wild-type parental toxin A-producing strains, two toxin A-deficient mutants (Tox-), or an elastase mutant. The infections produced by both Tox- mutants were less severe than infections produced by their parental strains. Furthermore, the Tox- mutants were not able to persist in the eyes as long as their parental strains. Addition of subdamaging doses of exogenous toxin A to eyes infected with the Tox- mutant PA103-29 significantly increased is virulence. The course of infection and the resulting corneal damage produced by the elastase mutant were indistinguishable from those of its parental strain.

A new type of hereditary cataract was predicted in the deer mouse (Peromyscus maniculatus) by the presence of syndactyly of the hind feet. Early morphologic changes were found in the equatorial cells that differentiated into new lens fibers. Later swelling at the anterior and posterior poles of these cells produced lens opacities. Anterior and posterior subcapsular cataracts progressed to a hypermature shrunken lens.

All patients greater than 50 years of age (N = 96) admitted with a pre- or postoperative diagnosis of acute appendicitis from 1971 to 1980 were reviewed. A comparative series of 91 patients aged 25 to 50 years was similarly reviewed. Noninflammatory diseases of the appendix and incidental appendectomies were excluded. Detailed study of symptoms, clinical presentation, laboratory evaluation, radiographic evaluation, concomitant diseases, hospital course, surgical findings, complications, and mortality were completed. Comparison of patients aged 25 to 50 to patients older than 50 years revealed a statistically significant increased incidence of perforation in the older group (p less than 0.0001). Sixty-five per cent of the older group showed greater incidence of perforation. Further analysis of this series yields the hypothesis that the increased incidence of perforation is related to a significant decrease in the frequency of classic presentation in the greater-than-50 age group, a significant decrease in frequency of correct admission diagnosis and a significant delay between admission and surgical procedure in the older group. A more rapid pathophysiologic progression of appendicitis with increasing age was noted. A much higher percentage of older patients was undiagnosed until the surgical procedure. In this group, there was a longer duration of symptoms, less frequent classic presentation, and decreased frequency of right lower quadrant guarding and tenderness as compared to patients with correct diagnosis prior to surgery. Complications were much more frequent in older patients and higher still in those with perforation. Analysis of findings by decade of life revealed an anticipated high incidence of perforated appendicitis in patients greater than 50, but also showed a continuation of the high incidence of perforation into the decade 40 to 50. There were three deaths in the entire study group (1.6%) all occurring in the older age group with postoperative sepsis.

Compartmental pressure measurement through an electromechanical process can be readily, accurately and inexpensively accomplished with standard hospital equipment. Best results will be obtained when personnel familiar with the set up and continued use of pressure monitoring equipment are assigned for the care and recording of data. The most frequently encountered problems associated with this technique are improper settings or inadequate calibration of pressure monitors and stopcocks or thrombosis of the wick catheter itself.

A new type of epidemic keratoconjunctivitis, caused by adenovirus type 19, occurred in Oregon in 1974. Although it can be spread by tonometry, in this epidemic finger-to-eye contact appeared to be the cause.