A 549, a human lung cancer cell line, spontaneously produces a tumor-derived immunosuppressive factor (TDSF) which inhibited PHA-stimulated T lymphocyte proliferation via a noncytotoxic mechanism. The inhibition increased in a dose-dependent pattern. The factor also markedly suppressed production of interleukin (IL-2) by PHA-stimulated lymphocytes and IL 2-dependent proliferation of activated lymphocytes. The fact that TDSF possessed very potent inhibitive action on IL-2 is especially noteworthy if we consider the use of IL-2 as immunotherapeutic agent. The synthesis of the factor was inhibited by mitomycin C, actinomycin D and cycloheximide, indicating that the factor is a genic product of A 549 cells. The factor is chemically a protein with a molecular weight greater than 150 KD and sensitve to extremes of pH, heating to 60 °C and trypsin treatment.

In the present study we cultured in vitro bone marrow cells from a patient with multiple myeloma (IgD) and researched into the modulation of supernatant media of various leukemic lines on the growth of culture cells. Cells in the cultures were studied for their morphological, biochemical, immunological and ultrastructural features. Drug sensitivity assay was also performed. The results showed that supernatant media of 6 cell lines promoted cell growth, but most remarkable stimulating activity was displayed by supernatant media from U937 and CEM. Cell cloning effect attained to more than 90 %. Cultured cells possessing biological characteristics of malignant cells were probably malignant cells from B cell lineage. This study indicated that long-term cultures of marrow cells might provide a tool useful for clinical and laboratory purpose and a method for studies on pathogenesis, regulation of hematopoiesis, cell differentiation and guide-way drugs.

Using five tumor cell lines, the effect of tumor-derived immunosuppressive factor(s) (TDSF) on T lymphocyte proliferation and its mechanism have been investigated. It was found that TDSF markedly inhibited PHA-stimulated T lymphocyte proliferation via a noncytotoxic mechanism. The inhibition increased in dose-dependent manner and the maximum inhibition was achieved when the factor was added at the initiation of the culture. When PBMC were preincubated with supernatants of tumor cells for 24 h, washed extensively and then cocultured with freshly prepared PBMC, similar suppressive effects were observed. The above results indicated that the activation of any suppressor cell subgroup may be one of the mechanisms of immunosuppressive action of TDSF.

In our experiment, lymphocyte membrane was 1abeled by DPH fluorescence probe. The rate of rotation of the probe can be measured from the value of fluorescence polarization (P_DPH). With this method useful information could be provided about membrane fluidity of lymphocytes. It was found that the F value (unit of lipid fluidity of membrane) of leukemic lymphocytes was obviously higher than that of normal ones. Furthermore, the F value of cultured leukemic T_s lymphocytes was the highest. In contrast with normal spleen T-lymphocytes or mixed lymphocytes, the response of malignant lymphocytes to the stimulation with ConA or PHA was reflected in the decrease of P_DPH value or the increase of F value. Unexpectedly, the F value of T-lymphocytes from “615” mouse not injected with tumour cells was also higher than that of the mixed. The possibility of using the membrane fluidity as a diagnostic criterion was also discussed.

TXB₂ and 6-keto-PGF₁ α levels in arterial and venous plasma of Wistar and Hilltop rats during hypoxia were measured to investigate the roles of TXA₂ and PGI₂ in hypoxic pulmonary vasoconstriction (HPV) and responsiveness difference of pulmonary vessels to hypoxia between different strains of rats. The results showed that PGI₂ might play an important role in maintaining the low resistance in pulmonary circulation of these two strains of rats. Increased TXA₂ during hypoxia may partially mediate HPV in Wistar rats, while augmented PGI₂ during hypoxia may modulate HPV in Wistar rats. This might be the important mechanism responsible for more intensive responsiveness of pulmonary vessels to hypoxia in Hilltop rats than in Wistar rats.

The purposes of this study were to localize the position of spinal center of sympathetic nerve which controls the pulmonary circulation, and to evaluate the role of pulmonary sympathetic nerve in hypoxic pulmonary vasoconstriction (HPV) in pithed rat model. The sympathetic preganglionic fibers arising from C₇–T₁₀ segments were stimulated electrically in succession. During stimulation the pulmonary vascular resistance (PVR) was increased in all segments tested, most significantly in C₇-T₄ (about 28 % above control value), obviously higher than that in T₅-T₁₀. The higher the stimulated spinal segments, the larger the ratio of ΔPVR/ΔSVR. Alveolar hypoxia (12%O₂–88% N₂) could induce HPV in pithed rat. In the presence of hypoxia, stimulation of T₁–T₃ segments caused a double increment in PVR and -P_p, as compared with those during normoxia (P<0.05). The data show that 1) the spinal center of sympathetic nerve regulating the vasomotion of pulmonary circulation is located in the C₇-T₄ segments; 2) the excitation of sympathetic nervous system during hypoxia could enhance HPV.

Adrenaline infusion to 8 rabbits led to remarkable dose-dependent hypokalemia. 2 of them died of ventricular arrhythmia (VA) with severe hypokalemia. In 6 rabbits with i.v. propranolol beforehand, no hypokalemia occurred after adrenaline infusion. Plasma catecholamines (CA) in 26 patients with AMI were greatly elevated at admission. 73% of relative hypokalemia (plasma potassium decreased to≥0.3 mmol/L) and a significant lowering of intraerythrocytic rate of Na/K were noted. These findings were inversely correlated with adrenaline. According to the multivariate analysis, both high level of plasma adrenaline and hypokalemia were responsible for VA in early AMI. The mechanism of CA-induced hypokalemia and its implications in AMI were discussed in detail.

To explore the role of HBV antigen expression and monocyte infiltrale in situ in chronic hepatitis, HBV markers and compositions and number of monocytes in the liver of chronic hepatitis B were immunohistochemically located and identified, and correlated with hepatocyle necrosis. It was found thai hepatic necrosis frequently took place in the centre or boundary of membranous HBsAg and/or HBcAg expression and the majority of monocytes accumulated in the necrotic areas showed CD₈⁺ cell token in HBeAg-positive stage of chronic active hepatitis. On the other hand, with HBeAg positivity converted into HBeAg-negativily or anti-HBe-positivily, HBV antigen expression significantly declined, CD₄⁺ cells remarkably increased as compared to HBeAg-positive status. These findings suggest that there may be distinct pathogenesis of hepatic necrosis in different stages of chronic HBV infection.

A vapid diagnostic assay for human cytomegalovirus (HCMV) has been developed for detecting HCMV DNA in urine samples with³²P-labelled cloned fragment, Eco RI fragment B, of DNA from HCMV strain Towne. 3.2 pg of homologous fragment from HCMV DNA could be detected by the labelled probe, and it did not hybridize DNA from other herpes viruses or human cells in dot hybridization assay. The assay correctly identified all (100%) of 7 coded urine specimen cultures positive for HCMV and 9 (90%) of 10 urine sample cultures negative for HCMV. So the hybridization assay was correct and as sensitive as the currently available tissue culture technique. The infection levels of different populations, such as organ transplantation recipients, patients with infantile hepatitis syndrome, normal infants, fetuses, have been investigated by the hybridization assay in the present study.

This paper presents four cases of pediatric extrasystole which did not fulfil the diagnostic criteria for parasystole. By calculating various ectopic intervals, we established the phase-response curve demonstrating that sinus electrotonic activities modulated the parasystolic focus in each case. Our results showed these cases to be modulated parasystole.

To assess the diagnostic significance of color Doppler and two-dimensional echocardiography and signs in aortic regurgitation (AR), we studied 48 patients with AR confirmed by color Doppler. On color Doppler, an abnormal diastolic flow originating from the aortic valve was visualized in the left ventricular outflow tract in the 48 cases. The maximal regurgitant jet area was 0.8–23.3 cm². On two-dimensional echocardiography, the appearance of cardiac chamber and valves did not offer a clue to the existence of AR in 12 patients (25 %). On physical examination, diastolic murmur was inaudible in 18 of 45 patients. Peripheral signs of AR were not found in 20 of 45 patients. In slight AR, signs were usually not detected. From the above we are led to conclude that of the patients with AR confirmed by color Doppler echocardiography, only 75 % could be detected by two-dimensional echocardiography and about 55 % diagnosed by physical examination.

Thrombi in test-tube, intraarterial thrombi and pig aorta wall were in vitro irradiated with continuous CO₂ laser, short pulsal and ultrashort pulsal YAG laser (with pulse-width of 10 ns and 40 ps, respectively) and their double frequency laser and excimer laser with a wave-length of 308 nm and pulse-width of 20 ns. Their effect of vaporizing and ablating (photodecomposing) thrombi and their thermal injuring effect on adjacent tissues were compared and assessed in order to select optimal laser with little thermal injuring and more rapid vaporizing or ablating thrombi effect for laser angioplasty. The experimental results showed that excimer laser, ultrashort puisai YAG laser and its double frequency laser, and double frequency laser of short puisai YAG laser, with laser beam and blood vessel kept in a coaxial position, can effectively vaporize or ablate thrombi without thermal injury to vessel wall. So they may be used for laser angioplasty. Of them, especially, excimer laser and double frequency laser of ultrashort puisai YAG laser have short wave-length and high peak power, and more effectively ablate thrombi than others, so they proved to be optimal lasers for laser angioplasty.

The interosseus posterior syndrome appears in two forms:

We report in this investigation about 12 operated patients with painful interosseus posterior syndrome. The intraoperative findings in the arcade of Frohse are compared with the findings we made at the preparation of 10 recently deceased. It was especially significant, that we found in 10 of our 12 cases intraoperatively a tendinous type of arcade. In our directioned cases we encountered this type of tendinous arcade in only 2 of 10 cases.

Based on these findings we are of the opinion that the tendinous arcade of Frohse is an important factor in the development of the interosseus posterior syndrome.