EFFECTS OF INTRACAROTID ADMINISTRATION OF β-PHENYL-γ-AMINOBUTYRIC ACID ON THE PERFUSED CAT BRAIN

An investigation was carried out on the effects of intracarotid administration of β-phenyl-γ-aminobutyric acid (β-phenyl-GABA) on the functions of a perfused cat brain. After injecting one ml, each of containing 1, 5, 10, 20, 25, or 35mg/ml of β-phenyl-GABA into the tubes perfusing the carotid arteries with standard artificial blood, the acute effects of the drug on EEG, cerebral blood flow, and oxygen consumption were observed. The results may be briefly summarized as follows.

• 1). EEG is inhibited shortly after the drug reaches the brain. The extent of inhibition rises and the duration of the inhibition is longer as the dose is increased.
• 2). β-phenyl-GABA increases the cerebral blood flow in the cat brain and the increase reaches its maximum with a dose of 5 mg. Above this dose it declines.
• 3). This drug increases the oxygen consumption of the brain slightly.
• 4). It has no effect on the systemic blood pressure.

     

Relapsing polychondritis diagnosed by transbronchial needle aspiration and 18F-fluorodeoxyglucose positron emission tomography/computed tomography

To the editor： The diagnosis of relapsing polychondritis may be difficult in the absence of typical attricular or nasal involvement. Airxay involvement is a major cause of morbidity and mortality.     

Effects of midazolam and diazepam as premedication on heart rate variability in surgical patients

We have examined the effects of midazolam 0.06 mg kg^–1i.m. and diazepam 0.2 mg kg^–1 orally as premedicationon the spectral components of heart rate (HR) variability in24 elderly patients aged 65–87 yr and 24 young patientsaged 18–35 yr undergoing elective surgery. The low-frequency/high-frequency(LF/HF) ratio of HR variability increased after arrival in theoperating room in elderly patients who received no premedication,but not in young patients. In elderly patients who receivedmidazolam or diazepam, the LF/HF ratio did not increase. However,diazepam increased the low-frequency component and the totalpower of HR variability in both young and elderly patients.We conclude that cardiac sympathetic nerve activity increasedafter arrival in the operating room in the elderly, that midazolamor diazepam reduced this increase and that diazepam caused anincrease in the total power of HR variability that has not beenobserved for other agents.     

Lymphokine mediated production of an epidermal cell proliferation factor by cultured murine bone marrow cells

The effect of cultured bone marrow cell supernatant (BMS) was studied on the proliferative response of cells of the transformed murine epidermal cell line Pam 212. Elevated DNA synthesis was found in Pam 212 cells cultured with BMS from bone marrow cells grown in spleen cell conditioned medium with concanavalin A (ConA). Pam cell proliferative activity was related to the histamine content in the culture supernatant. Neither spleen cell conditioned medium with IL1, IL2, or IL3 activity, nor ConA alone, showed any effect on Pam cell growth. A soluble mediator from the cultured bone marrow cells with mast cell characteristics was thought to be responsible for the stimulation of Pam cell growth, and Con A appeared to be a prerequisite for generation of this factor by the bone marrow cells.     

Complement activation in Brazilian pemphigus foliaceus

Brazilian pemphigus foliaceus is an autoimmune blistering skin disease of man that has a very high incidence in a confined geographical distribution. Rocket immunoelectrophoresis of plasma showed increased levels of complement fragments, C4d and Ba, indicating activation of complement through both the classical and the alternative pathways. Less sensitive methods such as CH50, total C3 and C4 did not demonstrate this activation, and immune complex measurements were within normal range. While complement may not be absolutely necessary for the development of skin lesions, our longitudinal studies show that activation of complement is at its highest during the most active phase of the disease.     

Studies on Hemodynamic Instability in Paroxysmal Supraventricular Tachycardia: Noninvasive Evaluations by Head-Up Tilt Testing and Power Spectrum Analysis on Electrocardiographic RR Variation

DOI, A., et al. : Studies on Hemodynamic Instability in Paroxysmal Supraventricular Tachycardia: Noninvasive Evaluations by Head-Up Tilt Testing and Power Spectrum Analysis on Electrocardiographic RR Variation. Hemodynamic instability is a crucial determinant of the best therapeutic option in paroxysmal supraventricular tachycardia (PSVT). However, it is still unclear if hemodynamic instability is tachycardia dependent or independent. We performed frequency-domain analysis of electrocardiographic RR variations during induced PSVT and head-up tilt tests after successful ablation to investigate the role of autonomic vasomotor function in hemodynamic instability during PSVT. Thirty-six patients with (syncope group,  n = 18  ) and without (nonsyncope group,  n = 18  ) syncope and/or presyncope during PSVT were enrolled in this study. Serial blood pressure, heart rate, and variations in heart rate during induced PSVT and head-up tilt tests were examined. Initial blood pressure fall and heart rate changes during induced PSVT were greater in the syncope group than in the nonsyncope group. A significant positive linear relationship was found between these two. Delayed blood pressure fall was observed in the syncope group, independent of heart rate changes. Syncope in PSVT could be predicted from the results of head-up tilt tests with 82% accuracy. Heart rate responses after isoproterenol infusion were significantly greater in the syncope group than in the nonsyncope group. The changes in low frequency to high frequency (LF:HF) values during induced PSVT and head-up tilt tests were significantly greater in the syncope group than in the nonsyncope group, and an exponential correlation was found between LF:HF changes in both tests. We conclude that PSVT rate and vasomotor reaction are related with hemodynamic instability during PSVT and head-up tilt testing is a useful method for determining if patients will have syncope during PSVT.     

Expression of heat shock protein 47 is increased in remnant kidney and correlates with disease progression

Glomerulosclerosis is characterized by accumulation of the mesangial extracellular matrix, including type I and IV collagen. The processing for the collagens in the glomeruli may play a critical role for development of glomerulosclerosis. We examined the expression of heat shock protein 47 (HSP47), a collagen-binding molecular chaperone in the progresive glomerulosclerosis model. Subtotally nephrectomized rats, unlike sham-operated rats, developed focal and segmental glomerulosclerosis. Immunological staining demonstrated an increased expression of HSP47 which paralleled the expression of type I and IV collagen in the glomeruli of the nephrectomized rats as the glomerulosclerosis developed. The mRNA levels encoding type I and type IV collagen and HSP47 were increased 3.4 fold, 3.6 fold and 2.8 fold, respectively, at week 7 after nephrectomy. By in situ hybridization, the expression of HSP47 mRNA was determined to be localized to the glomeruli with segmental sclerosis. These results suggest that HSP47 may play a central role in the process of extracellular matrix accumulation during the development of glomerulosclerosis.     

中医“辨证施治”理论指导下的医学学科辅导员职业发展标准探析

[目的] 分析医学学科辅导员职业现状,探索医学学科辅导员职业发展新标准。[方法] 以中医“辨证施治”理论为研究视角,“辨”发展之症结,“施”相应之措施,从医学学科辅导员所面对的工作群体以及工作环境的特殊性出发,研究医学学科辅导员职业发展新标准。[结果] 针对目前医学学科辅导员队伍结构不合理、职业认同度不高、职业压力过大、职业培训缺失等发展困境,总结出医学学科辅导员的职业发展标准应从提升医学职业道德、完善职业业务能力、增强多元职业素质、积极参与职业培训、深化落实职业考核等方面来完善。[结论] 医学学科辅导员作为医学生的领路人,需对其自身发展予以重视。希冀通过改革现行制度,明确职业发展标准,以增强医学学科辅导员队伍的立德树人能力,有效促进医疗卫生事业健康发展。     

Significance of sublobular hepatic necrosis in the progression of chronic hepatitis C

Abstract The clinical characteristics of hepatitis C virus associated chronic liver diseases (C-LD) in 17 patients were compared with hepatitis B virus associated diseases (B-LD) in 47 patients, by analysing the histological findings of the liver and the change in serum alanine aminotransferase (ALT) level. The persistence of the moderate abnormality in ALT (> 100 IU/L) for longer than 1 year was more frequently seen in the C-LD group ( P < 0.01), although the severe exacerbation of the disease with ALT higher than 500 IU/L was more frequent in the B-LD group ( P < 0.01). The patients with the histological finding of sublobular hepatic necrosis (SN) in the C-LD group progressed to advanced stages more frequently than those with SN in the B-LD group ( P < 0.05). Furthermore, nine of 10 patients with SN in C-LD finally progressed to hepatocellular carcinoma (HCC) in 52 ± 23 months, whereas three of 16 with SN in B-LD developed HCC in 81 ± 34 months. Although the morphological features of SN in C-LD and B-LD were almost the same, SN in C-LD seemed to be a more significant diagnostic condition for the progression to liver cirrhosis or HCC. The patients with SN in the C-LD group should be closely followed for the early detection of HCC, although further study with a greater number of patients is necessary.     

Polymerase chain reaction quantification of cytokine messenger RNA expression in peripheral blood mononuclear cells of patients with acute exacerbations of asthma: effect of glucocorticoid therapy

We have measured the expression of messenger ribonucleic acid (RNA) (mRNA) encoding inlerleukin-5 (IL-5), IL-4. IL-2 and interteron-γ (IFN-γ) in peripheral blood mononuclear cells (PBMC) from 10 patients with acute exacerbations of asthma and nine non-asthmatic controls. Measurements were repealed in seven of the asthmatics following 7 days of oral glucocorticoid therapy. Total RNA was extracted from the PBMC, reverse transcribed using oligo-(dT) primers and aliquots of the resulting complementary DNA (cDNA) amplified using the polymerase chain reaction (PCR) in the presence of cytokine-specific primers under non-saturating conditions. PCR products were quantified on a relative basis after Southern blotting and probing with radiolabelled internal oligonucleotide probes by computer assisted densitometry of blot autoradiographs. The relative amounts of IL-5 mRNA in PBMC from the asthmatic patients prior to glucocorticoid therapy were greater (P < 0.01) than those in PBMC from non-asthmatic controls. In contrast, there were no differences in the relative amounts of IL-4. IL-2 and IFN-γ mRNA. In the asthmatics, the relative amounts of IL-5 mRNA correlated with the peripheral blood eosinophil counts (P= 0.02). After oral glucocorticoid therapy of the asthmatics, lung function improved and the relative amounts of PBMC IL-5 mRNA were reduced (P= 0.04) and no longer differed from those in PBMC from non-asthmatic controls. Glucocorticoid therapy was not associated with significant changes in the relative amounts of PBMC IL-4. IL-2 and IFN-γ mRNA. PBMC from alopic subjects contained significantly greater quantities of IL-4 mRNA (P - 0.04) but not IL-5, IL-2 and IFN-γ mRNA compared with non-atopic subjects regardless of their asthmatic status. We conclude that PBMC of patients with acute exacerbations of asthma demonstrate elevated expression of mRNA encoding IL-5, but not IL-2, IL-4 and IFNγ and that the clinical improvement associated with glucocorticoid therapy is associated with a reduction of IL-5 mRNA expression. We further conclude that elevated expression in PBMC of mRNA encoding IL-4 is a feature of atopy but not of asthma. These observations suggest that IL-5 synthesis by activated T-lymphocytes may be relevant to the pathogenesis of asthma, and that inhibition of this release by glucocorticoids may at least partly explain their therapeutic effect in this disease.