Protective role of gamma/delta T cells and alpha/beta T cells in tuberculosis

Tuberculosis is a chronic infectious disease which causes major health problems globally. Although acquired resistance crucially depends on alpha/beta lymphocytes, circumstantial evidence suggests that, in addition, gamma/delta T lymphocytes contribute to protection against tuberculosis. We have studied Mycobacterium tuberculosis infection in TcR-delta-/- or TcR-beta-/- gene deletion mutants which completely lack gamma/delta T cells or alpha/beta T cells, respectively. Low inocula of M. tuberculosis led to death of TcR-beta-/- mice and transient disease exacerbation in TcR-delta-/- mutants. Infection with higher inocula caused rapid death of TcR-delta-/- mice. The development of and bacterial containment in granulomatous lesions was markedly impaired in TcR-beta-/-, and less severely affected in TcR-delta-/- mutants. Mycobacteria-induced IFN-gamma production by spleen cells in vitro was almost abolished in TcR-beta-/- and virtually unaffected in TcR-delta-/- mice. Our data confirm the crucial role of alpha/beta T cells in protection against established tuberculosis and formally prove a protective role of gamma/delta T cells in early tuberculosis.

Control of thymus-independent intestinal intraepithelial lymphocytes by beta 2-microglobulin

Murine intestinal intraepithelial lymphocytes (i-IEL) comprise thymus-dependent cells such as T cell receptor (TcR) alpha/beta CD8 alpha/beta+ i-IEL, as well as thymus-independent ones such as TcR alpha/beta CD8 alpha/alpha+ and TcR gamma/delta CD8 alpha/alpha+ i-IEL. Whilst the development of the CD8 alpha/beta expressing i-IEL is strictly contingent on major histocompatibility complex (MHC) class I surface expression, that of CD8 alpha/alpha i-IEL appears largely MHC class I independent. We have used beta 2-microglobulin (beta 2m)-/- mutant mice lacking surface-expressed MHC class I and TcR alpha/beta CD8 alpha/beta+ i-IEL to analyze the potential impact of MHC class I on regional activation of thymus-independent i-IEL. To analyze the role of TcR gamma/delta i-IEL in regional cell interactions, these mice were treated with the anti-TcR gamma/delta mAb, GL3. Whilst numbers of TcR alpha/beta CD8 alpha/alpha i-IEL were markedly reduced in beta 2m-/- mice, those of TcR gamma/delta i-IEL were elevated. Administration of GL3 in vivo caused TcR down-modulation and functional inactivation of TcR gamma/delta i-IEL in beta 2m+/- mice. In contrast, TcR expression and functional activities of TcR gamma/delta i-IEL from beta 2m-/- mice were not impaired by GL3 treatment. The TcR alpha/beta CD8 beta- i-IEL from beta 2m-/- mice were expanded and functionally activated as a consequence of TcR gamma/delta engagement. The TcR gamma/delta i-IEL and TcR alpha/beta CD8 alpha/alpha+ i-IEL from athymic nu/nu mice which express MHC class I, but lack TcR alpha/beta CD8 alpha/beta+ i-IEL, responded to TcR gamma/delta engagement as those from the beta 2m+/- controls. In addition, the TcR gamma/delta i-IEL from TcR beta-/- and TCR beta+/- mutants were equally affected by GL3. We conclude that the absence of beta 2m renders TcR gamma/delta i-IEL resistant to TcR-mediated inactivation and promotes activation of TcR alpha/beta CD8 beta- i-IEL. The activation of TcR gamma/delta i-IEL seems to be directly controlled by beta 2m/MHC class I expression and independent from TcR alpha/beta CD8 beta+ i-IEL. Regulation of self-reactive thymus-independent i-IEL through beta 2m/ MHC class I may contribute to control of autoreactive immune responses in the intestine.

The role of caregiver social networks in Alzheimer's disease

Although the theoretical importance of social networks in alleviating caregivers' mental distress when a family member has Alzheimer's disease is well-established, empirical support has been less definitive. For 58 patient-spouse caregiver dyads, we used an array of network variables within a causal model of stress. We found that: caregiver networks are associated with severity of illness but not duration; increased illness severity was associated with network members assuming new roles; social networks had indirect effects but no direct or buffering effects on caregiver psychological distress; religious attendance had direct and indirect effects on caregiver psychological distress. These findings point to the important, but complex, role that social networks play in affecting caregivers. However, because of its cross-sectional nature and the relatively small sample size, this study will require replication on larger samples using longitudinal analyses.

Baseline silent cerebral infarction in the Asymptomatic Carotid Atherosclerosis Study

BACKGROUND AND PURPOSE

In a group of patients with high-grade asymptomatic carotid artery stenosis, we prospectively determined the prevalence and radiological characteristics of clinically asymptomatic brain infarction evident on computed tomography. Risk factors and extent of carotid disease were also determined.

METHODS

Patients randomized into the Asymptomatic Carotid Atherosclerosis Study (ACAS) underwent a neurological history, a detailed stroke/transient ischemic attack questionnaire, and a detailed neurological examination. Computed tomography scans were examined by standardized criteria developed as part of a quality-control program supervised by a neuroradiologist. The presence, location, and size of all cerebral infarctions evident by computed tomography were determined.

RESULTS

Among 1132 patients, 848 had no history of stroke or transient ischemic attack. One hundred twenty-six patients (15%) had a silent infarct; 95 (11%) had one, 24 (3%) had two, and 7 (1%) had three or more infarcts. The infarct size was small and deep for 117 patients (72%), less than one-half lobe for 45 (28%), and one-half to less than one lobe for 1 (0.5%). The silent infarcts were evenly distributed ipsilaterally and contralaterally to the study artery but were significantly more frequent in the right hemisphere (P < .05). Factors associated with silent infarction were abnormal gait (P < .001), abnormal deep tendon reflexes or plantar responses (P = .038), but not degree of carotid stenosis. Silent infarction was less frequent among this totally asymptomatic cohort (15%) compared with those with transient ischemic attacks (34/139, 25%; P < .001).

CONCLUSIONS

Silent infarction in the setting of asymptomatic carotid stenosis is not uncommon, but silent infarctions are rarely sizable. The clinical significance of silent cerebral infarction in patients with asymptomatic carotid artery stenosis has yet to be established.

Crosstalk between alpha/beta T cells and gamma/delta T cells in vivo: activation of alpha/beta T-cell responses after gamma/delta T-cell modulation with the monoclonal antibody GL3

Although gamma/delta T cells express numerous in vitro functions similar to alpha/beta T cells, little is known about their biological functioning in vivo. Furthermore, it is unclear whether alpha/beta T cells and gamma/delta T cells act independently or in a coordinated way. In the present study, gamma/delta T cells were modulated in vivo by i.p. injection of the anti-gamma/delta T-cell receptor (TCR) monoclonal antibody GL3. GL3 administration caused disappearance of the gamma/delta TCR in spleen and lymph node cells and the gamma/delta TCR was reexpressed after in vitro cultivation for a few days. When cultured in vitro for 4 days, in the absence of foreign antigens, spleen and lymph node alpha/beta T cells from GL3-modulated mice showed vigorous proliferative responses. CD4 T lymphocytes from GL3-modulated mice produced interleukin 2, and CD8 T cells developed into cytolytic T lymphocytes in vitro capable of lysing syngeneic and allogeneic targets. Treatment with heat-inactivated GL3 or with normal hamster immunoglobulin did not cause any of these effects. These findings suggest that the anti-gamma/delta TCR monoclonal antibody GL3 modulates gamma/delta T cells in vivo and that this modulation has profound effects on alpha/beta T-cell reactivity. Hence, the data suggest a role for gamma/delta T cells in the regulation of alpha/beta T-cell activation in vivo.

Blood pressure during the first minutes of focal cerebral ischemia

STUDY OBJECTIVE

To determine whether blood pressure declines spontaneously during the first minutes and hours of focal cerebral ischemia.

DESIGN

Multiple blood pressure measurements as part of an urgent stroke therapy trial (treatment within 90 minutes of stroke onset).

SETTING

Thirteen hospitals in three metropolitan communities.

PARTICIPANTS

Sixty-nine patients (mean age, 65 +/- 9 years) with acute ischemic stroke who were participants in a phase I urgent stroke therapy trial of recombinant tissue plasminogen activator.

MAIN OUTCOME MEASURE

Blood pressures recorded at the scene of stroke by life-squad personnel, in the emergency department, and in the ICU.

RESULTS

The mean time from stroke onset to the time of first blood pressure measurement was 19 +/- 13 minutes. Twenty-four of the 69 patients in the urgent stroke therapy trial had an initial systolic blood pressure of at least 160 mm Hg. Of these, 23 had a significant decline in systolic and diastolic blood pressure during the first 90 minutes after the onset of stroke (mean change in systolic pressure, -29 +/- 22 mm Hg, P < .001; mean change in diastolic pressure, -10 +/- 14 mm Hg, P < .01). No patients received antihypertensive therapy during the time in which the decline in blood pressure was noted.

CONCLUSION

Mildly or moderately elevated blood pressure frequently declines spontaneously during the first minutes and hours of focal cerebral ischemia and generally does not require urgent pharmacologic treatment.

[Soluble interleukin 2 receptor as activity parameter in serum of systemic and discoid lupus erythematosus]

The evaluation of disease activity in systemic lupus erythematosus (SLE) is important for selection of the appropriate therapeutic regimen. In addition to the clinical picture, various laboratory parameters are taken into account. However, no validated criteria for the evaluation of the disease activity in SLE have yet been established. Recently, serum levels of soluble interleukin-2 receptor (sIL-2R) have been proposed as a potential parameter for disease activity in SLE. However, the studies reported on this subject so far have focused mainly on certain subsets of the disease, and the evaluation of the disease activity was based on a very limited number of parameters. In the present study, we determined serum levels of sIL-2R in 23 patients with SLE and 30 patients with discoid LE (DLE). Evaluation of disease activity in SLE was based on a comprehensive scale which considered numerous clinical signs and laboratory parameters. In SLE, serum levels of sIL-2R showed a better correlation with disease activity than all the other parameters investigated, including proteinuria, erythrocyte sedimentation rate, serum globulin concentration, titre of antibodies against double-stranded DNA, serum albumin concentration, serum complement levels and white blood cell count. For the first time, we report on elevated serum levels of sIL-2R in DLE, which also correlated with disease activity.

[Clarity in general practice]

A random sample of 224 consultations and interviews was analyzed, regarding the structuring and sequences in each consultation. Most space in the unbiased doctor's descriptions took anamnesis, followed by therapy, investigation, followed by physical examination and, least, diagnosis. Urban doctors kept the classic scheme of succeeding anamnesis, investigation, diagnosis and therapy more often than their rural colleagues. Explanations to patients were more frequently done by country doctors. The words doctors used to indicate communication are listed. The term of resonance phase in consultation is discussed. To achieve clarity in the consultation is important for doctor's stress prophylaxis.

Stereotaxic implantation of autologous adrenal medulla into caudate nucleus in four patients with parkinsonism. One-year follow-up

Four patients with levodopa-responsive parkinsonism (aged 26, 35, 45, and 49 years) received autologous adrenal medullary implants into or near the left caudate nucleus by stereotaxic implantation after flank adrenalectomy. All patients had an immediate response to implantation lasting several days, during which parkinsonian signs and symptoms decreased. This period was followed by a gradual reappearance of symptoms in all but one patient. This patient had had a dramatic increase in "on" time without dyskinesias and a decrease in the severity and duration of "off" time. He died of multifocal glioblastoma 1 year after transplantation. Autopsy revealed no surviving adrenal cells. In one case, the stereotaxic implantation missed the basal ganglia, resulting in the placement of the adrenal medullary tissue into the medial thalamus and near the third ventricle; the patient did not improve. In the other two cases, a modest but definite increase in "on" time without dyskinesia and a reduction in the severity and duration of "off" time has been observed. The role of autologous adrenal medullary transplantation in patients with parkinsonism remains to be determined. Patients with a family history of cerebral malignancy may be at increased risk for the development of transplant-induced malignancy.

Lead exposure from lead crystal

In a study of the elution of lead (Pb) from crystal decanters and glasses, port containing 89 micrograms Pb/l was placed in decanters and the Pb content of the wine rose steadily to 3518 micrograms/l after 4 months. Wines and spirits stored in crystal decanters for a long time contained Pb at concentrations up to 21,530 micrograms/l. In a short-term experiment white wine eluted small amounts of Pb from crystal glasses within minutes.

[Coincidence of hypertensive changes of the eye fundus and regulation disorders of peripheral microcirculation: I--Skin]

In cases of arterial hypertension, funduscopy is an established method of estimating systemic vascular lesions. In this study the relation between the extent of retinal vascular changes and dynamic processes in the microcirculation of the skin was investigated by nailfold capillaroscopy in 88 patients. With increasing vascular changes a progressive loss of vasodilator reserve and transcutaneous partial pressure was observed (no morphologic changes--fundus hypertonicus II--fundus hypertonicus III). It thus appears possible to evaluate the functional state of the macro- and microcirculation by funduscopy.

The hyperlipidemia of the nephrotic syndrome

Lipid abnormalities in patients with the nephrotic syndrome have long been recognized. However, the significance of these lipid abnormalities, the mechanisms producing them, and their potential treatment have all been a cause of debate. Recent data have helped clarify each of these areas of controversy. Studies of the lipoprotein abnormalities of patients with the uncomplicated nephrotic syndrome have shown that many will have elevated levels of total and low-density lipoprotein cholesterol, whereas only a few will have elevated levels of high-density lipoprotein cholesterol. If these lipid abnormalities have the same significance in this population as in other populations studied, then some patients with unremitting nephrotic syndrome will be at high risk for cardiovascular disease. The elevated cholesterol levels noted in the nephrotic syndrome are caused primarily by enhanced hepatic synthesis, with lesser contributions by decreased clearance and altered enzyme activities. The signal for enhanced hepatic lipogenesis may relate to changes in plasma albumin concentration, plasma oncotic pressure, a local effect of viscosity at the hepatic sinusoidal level, or a loss of urinary proteins or other liporegulatory substances. Recently, a number of short-term studies in nephrotic patients have documented the safety and efficacy of lipid-lowering drugs such as the bile acid-binding resins, probucol, and the HMGCoA (hydroxymethylglutaryl coenzyme A) reductase inhibitors.

Cognitive training in academically deficient ADDH boys receiving stimulant medication

This study evaluated the effectiveness of a 16-week intensive cognitive training program in stimulant-treated, academically deficient ADDH boys. Cognitive training focused exclusively on academic skills and tasks, and included attack strategy training as well as self-monitoring and self-reinforcement of problem-solving behaviors and response accuracy. Control groups included remedial tutoring plus medication, and medication alone. Despite the scope of the program, the results provided no support for the notion that academically based cognitive training ameliorates the performance and achievement of academically deficient ADDH youngsters. Further, this intervention did not enhance self-esteem or attributional perceptions of academic functioning. There was poor agreement between teacher ratings of academic competence and test score changes. The lack of concordance between measures, and the scarcity of academically deficient ADDH children are discussed.

Heat resistance, immunological and quantitative changes of neutrophil alkaline phosphatase in trisomy 21 pregnancies

Neutrophil alkaline phosphatase (NAP) was analysed in 25 pregnant women with trisomy 21 foetuses whose chromosomal aberration was recognized by cytogenetic study after amniocentesis. Enzyme investigation was performed at 20-22 weeks of gestation using cytochemical and biochemical techniques. Twenty-nine women at the same stage of normal pregnancies were selected as controls. In parallel, each mother was karyotyped. Ten subjects from each series underwent biochemical and immunological investigation: measurement of enzyme levels, thermostability study and immunological tests with alkaline phosphatase isoenzyme antibodies. NAP from pregnant women with trisomy 21 foetuses was characterized by: (1) a lower rate of enzyme activity, (2) a large amount of heat-stable enzyme (T = 56 degrees C for biochemical assays, T = 85 degrees C for cytochemical tests), and (3) a marked loss of liver antigenicity. These findings suggest the presence in trisomy 21 pregnancies of a non-specific alkaline phosphatase isoenzyme which appears as an "enzyme marker" in maternal circulating neutrophils.

An enzymatic marker in mothers of trisomy 21 children: neutrophil alkaline phosphatase

Neutrophil alkaline phosphatase (NAP) from 12 mothers of normal children was investigated and the results compared to those of 7 mothers with trisomy 21 offsprings, in an attempt to determine a parental molecular change in this chromosomal abnormality. The biochemical properties of the enzyme were analyzed by the procedures of isoenzyme characterization, i.e. enzyme assays, thermostability, inhibition patterns and slab gel electrophoresis. Immunological properties were determined on 5 samples from normal mothers and on the same sample number of mothers with affected children. In these latter NAP showed characteristics that were to some extent different from the ones of normal controls. The following changes were observed: highly significant loading of membrane and nucleus pellets in NAP activity, poor effect of inhibitors on thermostable component and immunodepletion measured by a significant decrease of the normal affinity for antiliver and antiplacental alkaline phosphatase antisera. These findings are discussed in the light of our knowledge of alkaline phosphatase isoenzymes.

Treatment of the hyperlipidemia of the nephrotic syndrome: a controlled trial

The hyperlipidemia of the nephrotic syndrome is often associated with elevated total and low-density lipoprotein (LDL) cholesterol levels and low or normal high-density lipoprotein (HDL) cholesterol levels. This pattern of hyperlipidemia has been associated with an increased risk of accelerated atherosclerosis in other populations. Despite extensive studies of diet and drug therapy in other populations, few such therapeutic studies exist in patients with the nephrotic syndrome. To investigate the effect of diet and lipid-lowering drugs on the lipoprotein-lipid profile of patients with unremitting nephrotic syndrome and marked hyperlipidemia, we conducted a controlled trial using two such drugs: colestipol and probucol. Colestipol lowered the mean total fasting plasma cholesterol of seven patients from 397 +/- 27 to 317 +/- 37 mg/dL, a 20.2% decrease, and lowered the LDL cholesterol from 398 +/- 28 to 203 +/- 18 mg/dL, a 31.9% decrease. It did not affect the HDL cholesterol level, and thus lowered the LDL-to-HDL cholesterol ratio. Probucol lowered the mean total cholesterol from 439 +/- 72 to 339 +/- 60 mg/dL, a 22.6% decrease, and the LDL cholesterol from 282 +/- 43 to 215 +/- 26 mg/dL, a 23.8% decrease. Although the HDL cholesterol was lowered from 49 +/- 9 to 43 +/- 7 mg/dL by probucol, a 12.2% decrease, the LDL-to-HDL cholesterol ratio still declined. Both drugs were well tolerated and proved safe in this short-term trial. Antihyperlipidemic therapy may well be indicated in certain patients with unremitting nephrotic syndrome.

Comparative investigation of the microcirculation in patients with hypertension and healthy adults

A total of 51 patients with arterial hypertension, 29 of which have renal dysfunction, were examined with regard to patient history, clinically, laboratory analysis and capillary microscopy. Compared to healthy adult patients with hypertension demonstrated a significant increase in the number of capillaries per millimeter of epidermis, while at the same time showing a significantly decreased erythrocyte column diameter. This observation was more pronounced the greater the degree of retinal vascular alteration (fundus hypertonicus). The duration of reactive hyperemia in response to three minutes of ischemia with a spygmonometer cuff was considerably shortened in patients with hypertension. Here as well, an increasing degree of retinal vascular alteration correlated with a decrease in reactive hyperemia to the point of no response at all. The blood fluidity of patients with arterial hypertension was significantly limited. The plasma viscosity as well as the erythrocyte aggregation were significantly elevated. Patients suffering from additional kidney dysfunction had even higher viscosities. There also appeared to be a correlation to the degree of fundus hypertonicus in which the plasma viscosity increased in relation to an increasing degree of retinal vascular alteration.

[Primary management of newborn infants with respiratory failure due to a congenital defect of the diaphragm]

The authors report on 36 premature and term infants with congenital defects of the diaphragm, including 17 patients who developed a severe respiratory insufficiency either immediately after birth or during the first 30 minutes of life. The overall mortality rate was 64%; the results of treatment were marked by a particularly high mortality rate among the patients with early respiratory insufficiency: out of 17 patients, 12 died. The evaluation of the courses confirmed that adequate preoperative primary care is of major prognostic importance in patients with early respiratory insufficiency. On the basis of personal experience the authors have formulated the following recommendations for improving diagnosis and therapy at this stage of care: greater use of sonography examination methods for antepartal diagnosis of congenital defects of the diaphragm, making it possible to treat the corresponding high-risk pregnancies at an early stage in clinics equipped for neonatologic and pediatric surgical treatment; early intubation respiration with a ventilation technique which does not overstrain the patient, in newborns with abnormal respiration and suspected congenital defects of the diaphragm; the great diagnostic importance of plain radiographs of the thorax and abdomen; neonatologic and intensive medical stabilization treatment in patients with severely suppressed metabolism prior to the anesthesiologic and surgical stress of closure of the diaphragm defect.

Recognition of vesicular lipoproteins by the apolipoprotein B,E receptor of cultured fibroblasts

Vesicular lipoproteins (e.g., lipoprotein-X) are found in plasma in cholestasis or following infusion of Intralipid or phospholipid. To investigate the metabolism of vesicular lipoproteins, we isolated them from the plasma of subjects with cholestasis or following chronic or single Intralipid infusion. Cholestasis and chronic Intralipid therapy were found to be associated with elevated plasma concentrations of apoE, as determined by radioimmunoassay. Vesicular lipoproteins purified from each of the three types of plasma contained apoE, as well as other proteins. In cholestasis, in which levels of apoE were up to five times normal, a major portion of the plasma apoE was on vesicular lipoproteins. Normalized for apoE content, all preparations of vesicular lipoproteins displaced 125I-labeled LDL from apoB,E receptors of cultured fibroblasts identically. This displacement was inhibited by monoclonal antibodies that block receptor binding of apoE. Vesicular lipoproteins containing 125I-labeled apoE were internalized and degraded by fibroblasts. Different preparations caused small losses or gains of cellular cholesterol, with appropriate stimulation or suppression of apoB,E receptors. Thus, vesicular lipoproteins contain apoE, and apoE mediates their interaction with the apoB,E receptor. Our results suggest that the catabolism of cholesterol-rich vesicular lipoproteins, formed during cholestasis or following infusions of Intralipid or phospholipid, may be receptor-mediated.

Radioactive iodine treatment of metastatic thyroid carcinoma with clinical thyrotoxicosis

We present a case of well-differentiated follicular carcinoma of the thyroid with hyperfunctioning metastases and clinical thyrotoxicosis. The recommended I-131 treatment dose for patients with widespread bone metastases from thyroid carcinoma is 200 mCi. However, in a patient with hyperfunctioning metastatic tumor and increased radioiodine uptake, the treatment dose should be modified. Radiation dosimetry measurements performed on the patient in this study demonstrated that 132 mCi would be a safe therapeutic I-131 dose which would avoid injury to normal radiosensitive tissues. Consequently, she was given a 130-mCi therapeutic dose.