Cellular responses to cytomegalovirus in immunosuppressed patients: circulating CD8+ T cells recognizing CMVpp65 are present but display functional impairment

The availability of tetrameric complexes of HLA class I molecules folded with immunodominant peptides makes it possible to utilize flow cytometry for rapid and highly specific visualization of virus specific CD8+ T cells. An alternate technique is to incubate whole blood with specific antigens and to subsequently detect and characterize responding T cells (e.g. by performing intracellular staining of interferon-gamma). By using an HLA-A2 tetramer construct folded with the same immunodominant CMV-peptide as that used for peptide pulsing, we monitored both the presence and functional capacity of CMV-specific CD8+ T cells. In addition T cell activation was assayed by determination of CD38 and CD69 expression. Twelve organ transplant patients and 31 healthy blood donors with latent CMV infection were investigated using CMV pp65 tetramer staining and intracellular staining of interferon-gamma after CMV pp65 peptide pulsing or CMV lysate pulsing. CMV-specific T cells were detected in similar absolute numbers as well as frequencies of T cells in the two groups investigated. However, the CMV-specific CD8+ T cells in immunosuppressed individuals showed a decreased functional response to the CMV-peptide, as evidenced by reduced interferon-gamma production when compared to healthy blood donors (19%; 42%, P < 0.005). In addition, CD38 expression was markedly higher in immunosuppressed patients compared to healthy blood donors (24%; 6%, P < 0.005). In a case report we demonstrate that reactivation of CMV can occur in an immunosuppressed patient with high number of CMV-specific T cells, but without functional capacity. Hence, these findings reflect impaired activation of cytotoxic T cells controlling latent CMV infection in immunosuppressed patients.     

Treatment of hyperthyroidism with standard doses of radioiodine aiming at ablation

Sixty patients with hyperthyroidism were treated with standard doses of 131I during 1969-83 in our department. The doses were 10-25 mCi (370-920 MBq), mostly 15 mCi (550 MBq). 38 of the patients have become hypothyroid, mostly within one year after treatment. There were 3 early relapses of hyperthyroidism; these patients became hypothyroid within one year after an additional dose of radioiodine. All hypothyroid patients had early substitution with l-thyroxine before overt clinical symptoms and signs had developed. There were no late relapses of hyperthyroidism. 15 patients had died during the follow-up; all were euthyroid or hypothyroid with adequate substitution. 28 of the 60 patients have been followed for 5-14 years, 14 for 2-5 years, 7 for 1-2 years and 10 for less than one year. Standard dose 131I treatment offers certain advantages compared with attempted individualized treatment. Late hypothyroidism after individualized dosage may be difficult to anticipate and detect, whereas early hypothyroidism after ablative standard dose treatment is easy to detect and control. Generally speaking, hypothyroidism is not to be regarded as a complication of radioiodine treatment for hyperthyroidism, but as its natural end result. The fixed dose schedule is especially well suited for regions where hyperthyroidism with no goitre or a small goitre is common.     

Rat tooth pulp cells elicit neurite growth from trigeminal neurones and express mRNAs for neurotrophic factors in vitro

Extracellular concentration of nitrite (NO2-), an oxidized product of nitric oxide (NO), was measured consecutively in the dorsal region of the rat suprachiasmatic nucleus (SCN) by means of in vivo microdialysis. The NO2- concentrations in the dialysates showed robust circadian rhythm under a 12:12 h light/dark cycle and were higher during the dark phase than during the light phase. When the rats were transferred to constant darkness, the 24 h rhythm of NO2- persisted without damping the amplitude. The NO2- level was significantly lowered by an injection of NO synthase inhibitor (NG-monomethyl-L-arginine, 10 mg/kg i.p.). These findings indicate that the daily fluctuation of NO2- in the dorsal region of the SCN, which represents endogenous rhythm of NO, is regulated independently of photic inputs into the SCN and may be related to the circadian clock functions.     

Expression of interleukin-6 in human dorsal root ganglion cells

The expression of Interleukin-6 (IL-6) was studied in normal dorsal root ganglia (DRG) of juvenile and foetal humans, using immunohistochemistry and in situ hybridization techniques. There was an expression of IL-6-like immunoreactivity in more than 75% out of neuronal cells in the juvenile ganglia with a peripheral localization, and also an expression in the foetal ganglion cells. There was a co-localization of IL-6 with substance P (SP) and calcitonin gene-related peptide (CGRP) in more than 60% of the DRG cells, respectively. By in situ hybridization 0.9% of the cells in the juvenile ganglia and 1.1% of the cells in the foetal ganglia showed a positive signal for IL-6. In addition, expression of IL-6 was found in juvenile medulla spinalis, preferentially in the white matter.     

Autonomic nerve function in children and adolescents with insulin-dependent diabetes mellitus.

Autonomic nerve function was assessed in 67 insulin-dependent diabetic children and adolescents and in 30 control subjects of the same age. The heart rate and blood pressure reactions to a deep breathing test (E/I ratio) and a tilt table test (acceleration and brake indices) were used. The E/I ratio, 1.54 +/- 0.21, and the acceleration index, 25 +/- 7.7, in the diabetic children were not significantly different from those of the control children, 1.51 +/- 0.16 and 24 +/- 7.5, respectively. Neither was any difference observed between the mean brake index values; 24.3 +/- 14.6 vs 23.5 +/- 7.5. However, the variance of the brake index in diabetic children was significantly higher than in control children (P less than 0.005). The brake index was negatively correlated to age in the healthy control children (r = -0.48, P less than 0.1). The acceleration index, but not the E/I ratio, also tended to be age related (r = -0.32, P less than 0.01 NS). No correlation was observed between sex, glycaemic control or duration of diabetes and the autonomic nerve function. Neither were severe hypoglycaemic episodes in diabetic children related to the autonomic nerve function. It is concluded that autonomic neuropathy is uncommon in diabetic children and adolescents and that age-related index values should be used when autonomic nerve function is evaluated in children of different ages.     

Effect of metabolic cage housing on immunoglobulin A and corticosterone excretion in faeces and urine of young male rats

Six 8-week-old Sprague-Dawley rats were studied for 9 days divided into three periods of 3 days each: before transferral to metabolism cages, during metabolic cage housing and after return to their home cages. Faeces were collected daily when the animals were housed in their home cages and every 6 h when the animals were housed in metabolic cages during which time urine was also collected every 6 h. The rate of weight gain was slightly reduced during the 3 days in metabolic cages and the animals produced significantly larger amounts of faeces when housed in metabolic cages than when housed in their home cages. The total faecal excretion of corticosterone (nanograms excreted per hour per kilogram body weight) and immunoglobulin A (IgA) (milligrams excreted per hour per kg body weight) quantified by enzyme-linked immunosorbent assays (ELISAs) exhibited a clear diurnal rhythm in the metabolic cage. Urinary excretions of corticosterone and IgA also followed a clear diurnal cycle. The mean daily amounts of corticosterone excreted were not significantly affected by cage change and by housing in metabolic cages. However, the excretion of faecal IgA was significantly reduced during the 3 days after the period in metabolic cages. Taken together the results indicate that metabolic cage housing is mildly stressful for young adult male rats.     

Variability in acquired resistance of Pasteurella and Mannheimia isolates from the nasopharynx of calves, with particular reference to different herd types

To measure the level of antimicrobial resistance in potential bovine respiratory pathogens at different production types, nasal swabs were collected from 57 calves of 13 dairy herds, 150 calves of 9 beef cattle herds, and 289 calves of 5 high-density veal calf herds and investigated for the presence of Pasteurellaceae. All calves were less than 6 months old. Susceptibilities of the Pasteurella and Mannheimia isolates to eight antimicrobials were determined using an agar dilution method. P. multocida (37.3%) and hemolytic Mannheimia organisms (M. haemolytica sensu lato) (6.3%) were the most frequently detected organisms. The overall prevalence of isolates resistant to at least one antimicrobial from the dairy, beef, and veal calves were 17.6% (6/34), 21.9% (14/64), and 71.9% (64/89), respectively. In isolates obtained on the veal calf herds, acquired resistance to ampicillin, oxytetracycline, potentiated sulfonamides, gentamicin, tilmicosin, and enrofloxacin was frequently present, and 32.6% of these isolates were resistant to more than two of the tested antimicrobials. Resistance to ceftiofur and florfenicol was not detected. A substantial within-herd variability of species diversity and resistance profiles among isolates belonging to the genera Pasteurella and Mannheimia was found among the isolates of the veal calf farms.     

Changes in the surface electromyogram during increasing isometric shoulder forward flexions

Summary When using electromyographic techniques in the evaluation of muscular load it is necessary to determine the mathematical relationship between the torque and the amplitude of the electromyographic signal. Isometric gradually increasing contractions up to 100% MVC can then be used. Often more than linear increases for the amplitude (RMS) — force regression have been reported. The present study was designed to test whether changes in power spectral density function take place during a gradually increasing isometric contraction (duration 10 s). Twenty-two clinically healthy females performed an increasing isometric shoulder forward flexion for 10 s using an isokinetic dynamometer. Electromyographic activity was measured in trapezius, deltoid, infraspinatus and biceps brachii using surface electrodes. Mean torque values were determined together with mean power frequency (MPF) and root mean square values (RMS) from the EMG signals for each 256 ms period. The RMS-torque regressions showed higher regression coefficients during the 6th to 9th sec than during the first 5 s. No significant correlation existed between MPF for the four muscles and the torque. A gradual decrease in MPF was generally found from the 6th s. It is concluded that this decrease in power spectral density function might have contributed to the significantly higher regression coefficient for the RMS torque regression at the high output part of the gradually increasing isometric contraction.