[PCR-SSCP analysis of p53 gene in human primary brain tumor]

In this study PCR-SSCP alalysis was made to detect the mutation of the exon 5-7 of p53 gene in 37 cases of human primary brain tumor. The results showed that 10 human primary brain tumors had mutation, of which 9 were gliomas (37.5%) and 1 was meningioma (7.7%), and that the higher the grade of tumor was, the higher would be the frequency of mutation. These results suggest that human primary brain tumor is related to p53 gene mutation and such mutation may be the major reason for human primary brain tumor genesis and malignancy.

Consecutive evaluation of immunoglobulin M and G antibodies against hepatitis E virus

Hepatitis E virus (HEV) infection is sporadic in the Guangzhou city southern China. However, the evaluation of antibodies to HEV during consecutive time periods after infection has not been reported. We utilized enzyme immunosorbent assay (ELISA) to defect IgM and IgG anti-HEV in consecutive serum specimens from patients with acute hepatitis E and compared that data with detection rates of IgM and IgG anti-HAV in patients with acute hepatitis A. IgM anti-HEV can be detected as early as 4 days after onset of disease symptoms in some patients. The detection rate of IgM anti-HEV is significantly higher in specimens collected within 4 weeks (95%) of onset than in those specimens collected 4 to 18 weeks after onset (67.6%) (P < 0.005). IgM anti-HEV had a similar pattern to IgM anti-HAV and can be used as a marker of acute HEV infection. In contrast with IgG anti-HAV, 56.8% of the specimens did not contain detectable levels of IgG anti-HEV (P < 0.005). One should be cautioned against making a diagnosis of HEV infection solely by the currently available assays for IgG anti-HEV. In conclusion, IgM anti-HEV can be used as a reliable and sensitive marker for recent HEV infection, but serum specimens should be collected within 4 weeks after onset of symptoms to avoid false-negative results. In contrast, we should be aware of the failure to develop IgG anti-HEV in some patients. These patients carry the risk of reinfection.

Role of endothelium-related mechanisms in the pathophysiology of renal ischemia/reperfusion in normal rabbits

The present study addressed the effect of interventions aimed to increase NO in the setting of acute renal ischemia/reperfusion (I/R) in uninephrectomized rabbits. In the 60-minute post-I/R period, L-arginine+superoxide (O2.-) dismutase (SOD) synergistically improved the renal functional (69.4% versus 10.4% of the pre-I/R glomerular filtration rate with or without L-arginine+SOD, respectively; p < .01) and histological parameters (82.9% decrease of medullary congestion in L-arginine+SOD, P < .01 versus vehicle) and blocked the I/R-dependent neutrophil accumulation (89.3% reduction). In spite of these results over the short term, a second set of experiments disclosed that the protection by L-arginine+SOD was no longer present at 24 and 48 hours (plasma creatinine in vehicle-treated versus L-arginine+SOD-treated animals [mg/100 mL]: 24 hours after I/R, 9.4 +/- 1.9 versus 8.07 +/- 0.65; 48 hours after I/R, 11.6 +/- 3.6 versus 9.7 +/- 0.9; P = NS in all the cases). Additional experiments were conducted using a milder 30-minute ischemic model, which showed no significant functional or histological protection by using L-arginine+SOD. In conclusion, our experiments disclosed the following: (1) the critical importance of the interaction between NO and O2.- in the acute protective effect of L-arginine (this effect not only improved renal function and histology but also reduced neutrophil accumulation) and (2) the discordance existing between the immediate protection afforded by L-arginine+SOD and the lack of protection observed at 24 and 48 hours. This finding suggests that a punctual intervention on the NO system at the time of I/R is not sufficient to reduce renal damage over the long term.

Role of endothelin in the pathophysiology of renal ischemia-reperfusion in normal rabbits

The present study addressed the acute effects of endothelin-1 on renal function and neutrophils accumulation in the setting of in vivo severe (60 min) acute ischemia/reperfusion. Ischemia/reperfusion decreased renal functional parameters and increased renal neutrophil accumulation and medullary congestion. All these parameters markedly improved with the intrarenal administration of anti-endothelin-1 antiserum. Comparatively, the intrarenal infusion of endothelin-1 decreased renal function and increased neutrophil accumulation. Abnormalities in renal histology were, however, less pronounced than with ischemia/ reperfusion. In experiments using rabbit isolated perfused kidneys, endothelin-1 induced the accumulation of labeled neutrophils. This accumulation was similar to that observed in kidneys obtained after 60 minutes of ischemia plus 60 minutes of reperfusion. Both endothelin and ischemia/ reperfusion effects were counteracted by an anti-endothelin antibody. In further in vitro studies, we found that endothelin-1-induced the expression of the CD18 antigens on the neutrophil surface. In subsequent experiments based on this effect of ET-1 on CD18 antigens, a blockade of both ischemia/reperfusion-induced and endothelin-1-induced neutrophil accumulation was obtained by infusion an anti-CD18 antibody. In conclusion, our experiments disclosed the critical role of endothelin-1 as a major promoter of early neutrophil accumulation after ischemia/reperfusion, which occurred through an integrin-mediated mechanism.

Active site of 5-aminolevulinate synthase resides at the subunit interface. Evidence from in vivo heterodimer formation

5-Aminolevulinate synthase (EC 2.3.1.37) is the first enzyme in the heme biosynthetic pathway of animals, fungi and some bacteria. It functions as a homodimer and requires pyridoxal 5'-phosphate as an essential cofactor. In mouse erythroid 5-aminolevulinate synthase, lysine 313 has been identified as the residue involved in the Schiff base linkage with pyridoxal 5'-phosphate [Ferreira, G. C., et al. (1993) Protein Sci. 2, 1959-1965], while arginine 149, a conserved residue among all known 5-aminolevulinate synthase sequences, is essential for function [Gong & Ferreira (1995) Biochemistry 34, 1678-1685]. To determine whether each subunit contains an independent active site (i.e., intrasubunit arrangement) or whether the active site resides at the subunit interface (i.e., intersubunit arrangement), in vivo complementation studies were used to generate heterodimers from site-directed, catalytically inactive mouse 5-aminolevulinate synthase mutants. When R149A and K313A mutants were co-expressed in a hem A- Escherichia coli strain, which can only grow in the presence of 5-aminolevulinate or when it is transformed with an active 5-aminolevulinate synthase expression plasmid, the hem A- E. coli strain acquired heme prototrophy. The purified K313A/R149A heterodimer mixture exhibited K(m) values for the substrates similar to those of the wild-type enzyme and approximately 26% of the wild-type enzyme activity which is in agreement with the expected 25% value for the K313A/R149A coexpression system. In addition, DNA sequencing of four Saccharomyces cerevisiae 5-aminolevulinate synthase mutants, which lack ALAS activity but exhibit enzymatic complementation, revealed that mutant G101 with mutations N157Y and N162S can complement mutant G220 with mutation T452R, and mutant G205 with mutation C145R can complement mutant Ole3 with mutation G344C. Taken together, these results provide conclusive evidence that the 5-aminolevulinate synthase active site is located at the subunit interface and contains catalytically essential residues from the two subunits.

Cervicofacial actinomycosis with paravertebral spread: a case report

We report a case of cervicofacial actinomycosis with paravertebral extension in a 60-year-old man who presented with recurrent neck masses. Diagnosis was confirmed on culture and histology of pus and debris obtained from surgical drainage. He improved only after lengthy in-hospital high dose penicillin therapy. He is currently well and is on maintenance doxycycline therapy for 6 months following the high dose penicillin therapy.

Acute sporadic hepatitis E virus infection in southern China

BACKGROUND/AIMS

The hepatitis E virus is responsible for epidemic and sporadic hepatitis in northwestern China, but its role as a cause of acute sporadic hepatitis in southern China has not been reported.

METHODS

We applied the most practical current methods for diagnosis of hepatitis E virus infection, IgM and IgG anti-HEV detection by enzyme linked immunosorbent assay, to investigate the prevalence of hepatitis E virus infection among acute sporadic hepatitis.

RESULTS

Anti-HEV IgM was found in 1 of 26 (3.8%), 4 of 20 (20.0%), 4 of 19 (21.1%), and 51 of 142 (35.9%), with acute hepatitis A, B, C and non-ABC, respectively. Anti-HEV IgM was not detectable in healthy subjects, while IgG anti-HEV was found in 14 of 77 healthy subjects (18.2%) and was long-lasting. Ninety-one cases without any evidence of hepatitis A, B or C infections and anti-HEV IgM were tentatively classified as non-A, B, C, D, E (non-ABCDE) hepatitis. By comparison with non-ABCDE, cases with hepatitis E were more frequently icteric and exhibited higher alanine aminotransferase levels (92.2% vs. 45.1%, 770 iu/l vs 377 iu/l, respectively, p < 0.005). Chronic cases were not observed in hepatitis E virus infections. However, 14 of 91 (15.4%) cases with non-ABCDE developed to chronicity (p < 0.005).

CONCLUSIONS

Hepatitis E virus infection is sporadic as well as endemic in southern China. Only IgM anti-HEV but not IgG anti-HEV can be used as an appropriate marker of acute hepatitis E virus infection. Superinfection of hepatitis E virus with other types of hepatitis viruses is frequent in this area. While the disease was associated with more severe clinical manifestations, patients usually recovered completely.

Typing and subtyping of influenza viruses in clinical samples by PCR

Type A and B influenza viruses can cause a wide spectrum of illness, and these viruses are responsible for considerable mortality and morbidity. Rapid typing of isolates is desirable when amantadine treatment or prophylaxis of contacts of type A influenza virus carriers is considered, but the available rapid techniques lack sensitivity and standard diagnostic methods require expansion of virus in tissue culture or embryonated hens' eggs. We developed a series of oligonucleotide primers able to detect, type, and subtype type A influenza viruses in a single reverse transcription-PCR. RNA was isolated from clinical specimens, and cDNA was generated with random primers. PCR was carried out with a mixture of primers specific for influenza viruses of types B, A/H1 and A/H3, and subtyping of the neuraminidase was carried out on the same cDNA template under identical conditions. Amplified products were detected by ethidium bromide staining of amplified products after agarose gel electrophoresis. When it was used to test 98 clinical specimens, this method was comparable to standard culture techniques in the detection, typing, and subtyping of influenza viruses.

[The effect of estrogen and its receptor antagonist on the growth of human gastric cancer cell line in vitro]

In this study, the effect was studied of estradiol (E2) and tamoxifen on the growth of a human gastric adenocarcinoma SGC-7901 cell line in vitro. Estrogen receptor as revealed by immunohistochemical staining was positive when added at various concentrations. E2 could significantly stimulate cell growth. The effect was most marked at concentration of 0.1 mumol/L. The cell doubling time was reduced, the plating efficiency was increased and c-myc oncogene expression was enhanced. Flow cytometric analysis indicated that cell] proliferation index was greater in the E2-treated than in the control. All these effects caused by E2 could be partially inhibited by the estrogen receptor inhibitor tamoxifen.

Chinese character operating system of traditional Chinese medicine and pharmacology (TCMP)

With the development in research, teaching and literature work in traditional Chinese medicine and pharmacology (TCMP) by means of computers, it has been found that the existing Chinese character operative systems cannot meet the need of carrying out information processing and software development in this field, since these systems do not include many of the common and special terms in TCMP. This makes it inconvenient to exchange academic thoughts in information processing in this field with our colleagues at home and abroad and greatly affects the sharing of the literature data in TCMP. It is therefore necessary to develop a Chinese character operating system applicable to the use of computers in the research of TCMP. Recently, we have developed jointly a Chinese character operating system of TCMP. This system is based on the original GB2312-80 Chinese character international code, to which are added 1,150 Chinese characters commonly used in TCMP. The five-stroke code, which make input possible according to word forms, are used for the input of expanded words. Besides, the system also provides the codes of a number of common names of Chinese materia medica, acupoint names, common terms in traditional Chinese medicine (TCM), TCM disease names, names of classic TCM works, etc. It also provides a convenient character-creating software. We hope that our work will lead to discussions concerning the difficult problems in computer processing of TCMP literature, i.e. the Chinese character.

[Treatment of recurrent carcinoma of the uterine cervix]

One hundred thirty seven patients with recurrent carcinoma of the uterine cervix were treated from 1964 through 1985. The primary treatment was surgery in 64 cases and radiation of 73 cases. Treatment consisted of surgery (n = 13) radiotherapy with or without Chinese medicine (n = 92), chemotherapy (n = 26), and chemotherapy plus radiation (n = 6). The mean 5-year survival rate of this series was 40.9%. One patient survived 28 year without tumor. Seven of 13 surgically treated patients were alive and free of disease for 5 to 28 years with an average 5-year survival rate of 53.8%. Thirty recurrent cases following radiotherapy were again treated by radiation, 11 of them (36.7%) were alive for 5 years.

Intracellular glutathione influences collagen generation by mesangial cells

The cellular redox state is altered in a number of pathological conditions, including various forms of glomerular injury and diabetes. For example, glucose, via the pentose phosphate pathway generates NADPH, which maintains glutathione (GSH) (part of a major intracellular reducing system) in its reduced state. GSH in turn influences the activity of transcription factors on gene expression. We therefore examined whether changes in cellular GSH influence total collagen synthesis and mRNA levels for collagen I, collagen IV and TGF-beta in SV-40 transformed mouse mesangial cells (MC) maintained in either 5 or 25 mM glucose media. Total intracellular GSH was increased by N-acetylcysteine (NAC; 10 mM) or decreased with the GSH synthesis inhibitor buthionine sulfoximine (BSO; 0.2 mM) in MC. NAC increased 3H-proline incorporation into collagenase-sensitive protein while BSO decreased it under both glucose conditions. The presence of BSO did not reverse the increased collagen synthesis seen in the NAC stimulated cells. Northern blot analysis showed increased mRNA levels for collagen I, collagen IV and TGF-beta in cells grown in high glucose (25 mM). NAC increased the mRNA for all three compounds while BSO alone had no effect on these mRNA levels. However, BSO reversed the increased mRNA levels for collagen I, IV and TGF-beta seen in the presence of NAC. These findings suggest that the cellular redox state may influence gene transcription in MC, and may have implications in explaining injury-associated alterations of mesangial matrix generation.

Rat gastric motor response to food protein-induced anaphylaxis

BACKGROUND/AIMS

Antigen challenge of sensitized rats leads to delayed gastric emptying, but the mechanism (gastroparesis or prolonged trituration) and mediators are unknown.

METHODS

Hooded Lister rats were sensitized by intraperitoneal injection of egg albumin as antigen, and control rats were sham-sensitized. On day 14, antral manometric and antroduodenal myoelectric activities in sensitized and sham-sensitized rats were recorded in response to antigen challenge, and the contractility of gastric antral circular muscle strips (mucosa intact) in standard tissue baths was measured in response to antigen or other agents.

RESULTS

In vivo, the intragastric antigen challenge of sensitized (but not sham-sensitized) rats provoked diarrhea, reduction in the antral motility index, and disruption of the duodenal migrating motor complex. In vitro, antigen induced a tonic contraction of antral circular muscle segments from sensitized animals. Doxantrazole, but not disodium cromoglycate, inhibited antigen-induced contraction. Whereas histamine, 5-hydroxytryptamine, prostaglandins, leukotrienes, and platelet-activating factor contracted gastric muscle strips, neither specific antagonists, prostaglandin synthase, or 5-lipoxygenase inhibitors inhibited antigen-induced contraction. Tetrodotoxin increased antigen-induced contraction; however, the antigen-induced contraction was unaffected by atropine, guanethidine, or NG-nitro-L-arginine methyl ester.

CONCLUSIONS

Food protein-induced, immunoglobulin E-mediated delayed gastric emptying in sensitized rats is associated with a transient reduction in gastric antral contractions. Antigen-induced contraction appears to be under nonadrenergic, noncholinergic, nonnitroxinergic inhibitory neural control.

Follow-up study of acute hepatitis C

An extended follow-up study of hepatitis C virus (HVC) infection was conducted in Guangzhou and its nearby regions on patients hospitalized with acute hepatitis. Routine screening of blood donors for HCV was not yet instituted at the time of this study. HCV was found to be a common cause of the disease, and the infection had a close association with recent histories of blood transfusion. Sequential sera obtained from patients during hospitalization and after discharge were tested for the presence of HCV antibodies by the first and the second generation of commercial test kits, for levels of alanine aminotransferase (ALT), and for the presence of HCV-RNA. The development of HCV antibodies in some of the patients may be delayed for protracted period following clinical onset. HCV-RNA was only intermittently detectable both before and after seroconversion. Six of 33 patients studied showed seroreversion and 5 of them were accompanied by loss of HCV-RNA and serum ALT returned to normal levels. The disease persisted in 24 of 27 patients without seroreversion, accompanied by intermittent detection of HCV-RNA throughout the protracted course of the infection. Our results indicate that both EIA for detection of HCV antibodies and PCR for serum HCV-RNA should be used in combination for reliable diagnosis of HCV infection and screening of blood for transfusion.

Both physiological and pharmacological levels of melatonin reduce DNA adduct formation induced by the carcinogen safrole

Hepatic DNA adduct formation induced by the chemical carcinogen, safrole, was suppressed by both endogenous pineal melatonin release and by the exogenous administration of melatonin to rats. DNA damage after administration of of melatonin to rats. DNA damage after administration of 100 mg/kg safrole (i.p.) was measured by the P1 enhanced 32P-postlabeling analysis method. The RAL (relative adduct labeling) x 10(7) of carcinogen modified DNA in the liver of untreated controls and in safrole treated animals killed during the day, at night, after pinealectomy and pinealectomy plus melatonin injection (0.15 mg/kg x 4 or a total of 0.6 mg/kg) was 0, 12.6 +/- 0.75, 10.9 +/- 0.72, 13.6 +/- 1.12 and 5.7 +/- 0.53 respectively. For the same groups of animals, circulating melatonin levels at the termination of the study were 31 +/- 3, 29 +/- 2, 276 +/- 31, 24 +/- 1 and 13,950 +/- 1016 pg/ml serum respectively. The higher the melatonin concentration in the serum the lower was DNA adduct formation in the rat liver. Thus, high nocturnal levels of melatonin were protective against safrole-induced DNA damage. These findings indicate that the functional pineal gland plays an important role in oncostatic actions of carcinogens such as safrole. At physiological levels, melatonin seemed to prevent especially the formation of what was referred to as the N1 DNA adduct. Melatonin's ability to suppress DNA adduct formation may relate to its inhibitory effect on a mixed function oxidase, cytochrome p-450, and on the recently identified hydroxyl radical scavenging capacity of the indole. The oncostatic action of melatonin is also suggested by its nuclear accumulation and DNA stabilization characteristics. At pharmacological levels melatonin is extremely potent in preventing DNA modification induced by the chemical carcinogen, safrole.

Excimer laser photorefractive keratectomy in Singapore--a new treatment modality for myopia

BACKGROUND

Myopia is a national epidemic in Singapore. Photorefractive Keratectomy (PRK) for the treatment of myopia using the Argon Fluoride Excimer Laser commenced in January 1992 at the Singapore National Eye Centre.

METHODS

An open, prospective, non randomised clinical trial to assess the efficacy, predictability, stability, and safety of PRK for the correction of myopia between -2.0 to -6.0 dioptres.

RESULTS

One hundred and fifty-five eyes of one hundred and thirty-five patients underwent PRK between January and September 1992, of which thirty-one had completed at least six months of follow-up. Twenty-nine of the thirty-one patients (93.5%) achieved an unaided visual acuity of at least 6/12. Twenty-six patients (83.9%) were within 1 dioptre of emmetropia. There was an initial over-correction in all patients which regressed to a plateau at around three or four months. Corneal haze did not pose a significant problem. Three patients had ocular hypertension, and another developed a mild allergic reaction to the antibiotic-steroid ointment.

CONCLUSIONS

Excimer Laser Photorefractive Keratectomy is a very effective, fairly predictable, stable and safe surgical method for the treatment of myopia.

Personal experience of right anterior segmentectomy (segments V and VIII) for hepatic malignancies

BACKGROUND

Right anterior segmentectomy is the most difficult type of hepatic resection to perform and is reported only rarely. For patients with tumors limited to the anterior segment but complicated by mild liver dysfunction, this is the only type of hepatectomy that can be tolerated. This article described personal experience with this operation in 17 patients with liver malignancies.

METHODS

Fourteen patients had hepatocellular carcinoma, one had cholangiocellular carcinoma, and two had metastases, one from rectal and the other from gastric carcinoma. Except in one case of dense adhesion of the hepatoduodenal ligament, hemihepatic vascular occlusion was used. Both the right and middle hepatic veins were fully exposed in 14 patients.

RESULTS

The average operation time was 412 minutes and the average blood loss was 1482 ml. There was one operative death as a result of pneumonia and liver failure. Another patient had prolonged bile leakage with right pleural effusion and bleeding gastric erosions. The cumulative 1- and 5-year survival rates were 88% and 47%, respectively.

CONCLUSIONS

The results of this experience indicate that in selected patients with hepatic malignancies this procedure is safe and compatible with improved survival. This may be the first report to describe the clinical features and operative technique in a series of patients treated by right anterior segmentectomy.

Treatment of fever due to exopathic wind-cold by rapid acupuncture

57 cases of common cold, influenza, acute tonsillitis and acute bronchitis were treated by rapid needling with filiform needles at Dazhui (Du 14), Fengchi (GB 13), and Quchi (LI 11). The indices for observation were first determined, and the 19 cases that manifested an axilla temperature drop of over 1 degree C after treatment and a ratio of < 0.3 of the main symptom scores after treatment were regarded as markedly effective; the 27 cases that manifested an axilla temperature drop of 0.5-1.0 degree C and a symptom score ratio of 0.3-0.6 were regarded as effective, and the 11 cases that manifested an axilla temperature drop of < 0.5 degrees C and a symptom score ratio of > 0.7 were regarded as failures. The total effective rate was 80.7%. Analysis of the individual patients indicated that the peripheral blood leucocyte and lymphocyte counts differed insignificantly after needling, while the body temperature, rate of respiration, pulse, blood pressure and acupoint temperature all dropped, with a simultaneous increase in the percentage of T-lymphocytes. The immediate effects were especially marked in fevers due to exogenous wind and cold.

Dietary palmitic and oleic acids exert similar effects on serum cholesterol and lipoprotein profiles in normocholesterolemic men and women

To compare the effects of dietary palmitic acid (16:0) vs oleic acid (18:1) on serum lipids, lipoproteins, and plasma eicosanoids, 33 normocholesterolemic subjects (20 males, 13 females; ages 22-41 years) were challenged with a coconut oil-rich diet for 4 weeks. Subsequently they were assigned to either a palm olein-rich or olive oil-rich diet followed by a dietary crossover during two consecutive 6-week periods. Each test oil served as the sole cooking oil and contributed 23% of dietary energy or two-thirds of the total daily fat intake. Dietary myristic acid (14:0) and lauric acid (12:0) from coconut oil significantly raised all the serum lipid and lipoprotein parameters measured. Subsequent one-to-one exchange of 7% energy between 16:0 (palm olein diet) and 18:1 (olive oil diet) resulted in identical serum total cholesterol (192, 193 mg/dl), low-density lipoprotein cholesterol (LDL-C) (130, 131 mg/dl), high-density lipoprotein cholesterol (HDL-C) (41, 42 mg/dl), and triglyceride (TG) (108, 106 mg/dl) concentrations. Effects attributed to gender included higher HDL in females and higher TG in males associated with the tendency for higher LDL and LDL/HDL ratios in men. However, both sexes were equally responsive to changes in dietary fat saturation. The results indicate that in healthy, normocholesterolemic humans, dietary 16:0 can be exchanged for 18:1 within the range of these fatty acids normally present in typical diets without affecting the serum lipoprotein cholesterol concentration or distribution. In addition, replacement of 12:0 + 14:0 by 16:0 + 18:1, but especially 16:0 or some component of palm olein, appeared to have a beneficial impact on an important index of thrombogenesis, i.e., the thromboxane/prostacyclin ratio in plasma.

Effects of intravenous infusions of diaspirin cross-linked hemoglobin (DCLHb) on sheep

The purpose of this study was to compare the cardiopulmonary, hematologic, and immunologic responses of unanesthetized sheep to single, "topload", intravenous infusions of either 10 mL/Kg or 40 mL/Kg of Diaspirin Cross-Linked Hemoglobin, 10 mL/Kg or 40 mL/Kg of a Human Serum Albumin (HSA) solution oncotically adjusted with human serum albumin to approximately match the oncotic pressure of the DCLHb, or 10 mL/Kg of Erythrocyte Hemolysate solution prepared in a manner similar to that commonly described in the literature and referred to as "stroma free hemoglobin". Solutions were infused at a rate of 1 mL/Kg/minute and animals were monitored for 72 hours after infusion. These studies demonstrated that in sheep infusion of either DCLHb or HSA solutions was well tolerated and did not produce a significant increase in plasma C3a levels, an increase in the plasma concentration of thromboxane B2, or unexpected fluid shifts. In contrast, infusion of the Erythrocyte Hemolysate produced a greater than 10-fold increase in plasma C3a concentrations, a greater than 6000-fold increase in plasma TxB2 concentration, significant fluid shifts, and changes in a variety of other parameters consistent with induction of a dramatic inflammatory response. These results indicate that appropriately prepared and purified DCLHb solutions do not elicit an inflammatory reaction in sheep.

Treadmill exercise testing in ischaemic heart disease

An analysis of 1,600 consecutive treadmill exercise tests is made, with emphasis on those with an ischaemic response. An ischaemic response is defined as a horizontal or downsloping depression of the ST segment of 1 mm or more. A hypertensive response is recorded where the blood pressure exceeds 200 mm Hg systolic or 100 mm Hg diastolic during exercise. There were 150 (9%) ischaemic responses and 279 (17%) hypertensive responses. Cardiac arrhythmias were detected in 173 (11%) subjects. Among the 150 subjects with ischaemic responses, 69 (46%) of them presented with anginal symptoms while 64 (43%) of them had no precordial pain. Twenty-seven (18%) of them had definite previous myocardial infarction. Risk factors observed included hypertension in 54 (36%) subjects, diabetes mellitus in 33 (22%) subjects, hypercholesterolaemia in 41 (37%) out of 112 subjects and 44 (29%) cigarette smokers.

Clinical aspects of treadmill exercise testing

A study is made of 525 consecutive treadmill exercise tests. Horizontal or downsloping ST segment depression of 1 mm or more was considered or ischaemic response. A systolic blood pressure exceeding 200 mm Hg or a diastolic blood pressure exceeding 100 mm Hg during or after exercise was defined as a hypertensive response. An ischemic response was found in 48 subjects. In this group, 7 (15%) had previous myocardial infarction, 10 (21%) had minor ischaemic changes in the resting electrocardiogram. Twenty-eight (58%) complained of precordial pain or discomfort. A hypertensive response occurred in 101 subjects. Thirty-eight of them had precordial pain or discomfort. The resting blood pressure was elevated in 52, borderline in 32, and normal in 17 subjects. Cardiac arrhythmias were detected in 53 patients. Other abnormalities detected included 3 cases of hypertrophic cardiomyopathy and 1 case of post exercise bronchospasm due to propranolol.