Relationships Between β2-Microglobulin and Alloantigens Coded for by the Major Histocompatibility Complexes of the Rabbit and the Guinea Pig

Treatment of rabbit and guinea pig lymphocytes with Fab' fragments of anti-beta2-microglobulin completely inhibited the cytotoxic effects of alloantisera to RLA or GPLA antigens, respectively. Aggregation of beta2-microglobulin on the lymphocyte surface by successive incubations with goat anti-beta2-microglobulin on the lymphocyte surface by successive incubations with goat anti-beta2-microglobulin and F(ab')2 fragments of rabbit anti-goat IgG also made rabbit lymphocytes resistant to lysis by anti-RLA, and guinea pig lymphocytes resistant to lysis by anti-RLA, and guinea pig lymphocytes resistant to lysis by anti-GPLA. The two kinds of pretreatment of guinea pig lymphocytes did not affect the cytotoxicity of antisera directed against guinea pig Ia antigens. These results in conjunction with previous findings in the mouse and in man suggest that beta2-microglobulin on the lymphocyte surface in mammals is generally associated with major serologically defined histocompatibility antigens but not with I-region-associated antigens.     

Thickness of the patella in men and women with osteoarthritis

The maximum thickness of the patella was prospectively measured during 216 primary total knee arthroplasties (TKA) that included patellar resurfacing. Of the measured patellae, 93 were in 75 men and 123 were in 99 women. Average patient age was 68.9 years for men and 71.2 years for women. All patients were diagnosed with osteoarthritis. Mean maximal patellar thickness in men was 26.1 mm and in women it was 22.6 mm. This difference was significant (P < 0.0001). It is recommended that preoperative patellar thickness be restored following patellar resurfacing. The values for patellar thickness in men and women with osteoarthritis which we have noted may serve as a guide to patellar thickness restoration in cases of patellar dysplasia and in revision TKA where preoperative patellar thickness may be unknown.     

Systemic and centrally mediated angiotensin II effects in the horse

The primary aim of the study was to evaluate the potential value of intravenous (i. v.) infusion of angiotensin II (AII) for phonocardiographic differential diagnosis of equine valvular insufficiency. Ten-minute AII infusions at 4.5–33 pmol kg^-1 min^-1 induced clear-cut dose-dependent rises in systemic arterial blood pressure (aBP), whereas the pulmonary aBP remained largely unaffected. It implies that i. v.infusion of All at about 10 pmol kg^-1 min^-1 could be a valuable tool for the acoustic differentiation between mitral and tricuspid valvular dysfunction in the horse. The infusion at, and above 9 pmol kg^-1 min^-1 caused increased heart rate. This chronotrophic effect was not strictly dose-dependent and exhibited significant tachyphylaxis. Angiotensin II administration at, or above 9 pmol kg^-1 min^-1 was needed to induce an urge to drink, suggesting that angiotensin-induced thirst does not appear in the euhydrated horse until the octapeptide reaches supraphysiological blood concentration. Determinations of plasma aldosterone concentration (PA) revealed comparatively high morning control values (269 ± 46 pmol^-1).Three consecutive AII infusions with 10-min intervals and at increasing dosages caused a cumulative, almost fourfold elevation of PA.The PA pattern indicated that AII-induced hypersecretion of aldosterone continued for several minutes after the end of the infusions, but also showed that the metabolic clearance of the hormone took precedency of the secretion within 20 min post-infusion. In two of the horses a fall in PA occurred during a fourth, final infusion, indicating that in these instances the previous AII administration had impoverished the store of aldosterone available for release from the adrenal cortex.     

Elimination of CD8+ T Cells in Vivo Does Not Break Induced Immunospecific Tolerance to Experimental Allergic Neuritis in Rats

The role of CD8+ T 'cytotoxic/suppressor' T cells in induced immunospecific tolerance and during recovery after actively induced disease was examined by means of elimination of CD8+ cells from Lewis rats using in vivo treatment by Ox8 monoclonal antibodies, in experimental allergic neuritis (EAN). Animals depleted of CD8+ T cells after recovery from EAN did not show any clinical signs of relapse. Other animals were pretreated with the peripheral nerve basic protein P2 and thereby rendered resistant to disease induction with a potentially neuritogenic emulsion. The elimination of CD8+ T cells did not result in EAN here either. Thus, the CD8+ T-cell population does not seem to participate in the suppression of this autoimmune disease under these experimental conditions.     

Recent developments in home total parenteral nutrition

Home parenteral nutrition (HPN) support has been an advancing therapy in the past 30 years. Patients who previously had no options to sustain their lives are now able to live at home, maintain employment, and continue with most daily activities. Although this therapy has been innovative and successful, it requires great financial and professional resources. The expense of HPN makes most patients dependent on third-party payment, and the complications can result in frequent hospitalizations and may be life-threatening. For these reasons, extensive training of the patient and caregivers is necessary. Thorough and time-consuming monitoring by a multidisciplinary team of professionals is also essential. Home care and supply companies offer services that make the process of home TPN easier for the patient and the healthcare team. Advances in the area of home nutrition support are expected to continue as the demand for this therapy rises.     

A prospective population-based study of pediatric trauma patients with mild alterations in consciousness (Glasgow Coma Scale score of 13-14)

OBJECTIVE: Considerable controversy surrounds the appropriate evaluation of children with mild alterations in consciousness after closed head trauma (Glasgow Coma Scale [GCS] score of 13-14). The objective of the current study was to determine the incidence of intracranial lesions in pediatric patients with a field GCS score of 13 or 14 after closed head injuries. METHODS: The current study is a population-based, multicenter prospective study of all patients to whom emergency medical services responded during a 12-month period. The setting was urban Los Angeles County, encompassing a patient population of 2.3 million children, 13 designated trauma centers, and 94 receiving hospitals. RESULTS: In the pediatric age group (<15 yr old), 8488 patients were transported by emergency medical services for injuries. Of these, 209 had a documented field GCS score of 13 or 14. One hundred fifty-seven patients were taken to trauma centers, and 135 (86%) underwent computed tomography. Forty-three patients (27.4%) had abnormal results on computed tomographic scans, 30 (19.1%) had an intracranial hemorrhage, and 5 required an operative neurosurgical procedure for hematoma evacuation. Positive and negative predictive values of deteriorating mental status (0.500 and 0.844, respectively), loss of consciousness (0.173 and 0.809), cranial fracture (0.483 and 0.875, and extracranial injuries (0.205 and 0.814) were poor predictors of intracranial hemorrhage. CONCLUSION: Pediatric patients who have mild alterations in consciousness in the field have a significant incidence of intracranial injury. The great majority of these patients will not require operative intervention, but the implications of missing these hemorrhages can be severe for this subgroup of head-injured patients. Because clinical criteria and cranial x-rays are poor predictors of intracranial hemorrhage, it is recommended that all children with a GCS score of 13 or 14 routinely undergo screening via non-contrast-enhanced computed tomography.