[Pathological significance of plasma cell infiltration in diagnosing lymph node diseases]

Objective: To investigate the value of plasma cells for diagnosing lymph node diseases. Methods: Common lymphadenopathy (except plasma cell neoplasms) diagnosed from September 2012 to August 2022 were selected from the pathological records of Changhai Hospital, Shanghai, China. Morphological and immunohistochemical features were analyzed to examine the infiltration pattern, clonality, and IgG and IgG4 expression of plasma cells in these lymphadenopathies, and to summarize the differential diagnoses of plasma cell infiltration in common lymphadenopathies. Results: A total of 236 cases of lymphadenopathies with various degrees of plasma cell infiltration were included in the study. There were 58 cases of Castleman's disease, 55 cases of IgG4-related lymphadenopathy, 14 cases of syphilitic lymphadenitis, 2 cases of rheumatoid lymphadenitis, 18 cases of Rosai-Dorfman disease, 23 cases of Kimura's disease, 13 cases of dermal lymphadenitis and 53 cases of angioimmunoblastic T-cell lymphoma (AITL). The main features of these lymphadenopathies were lymph node enlargement with various degrees of plasm cell infiltration. A panel of immunohistochemical antibodies were used to examine the distribution of plasma cells and the expression of IgG and IgG4. The presence of lymph node architecture could help determine benign and malignant lesions. The preliminary classification of these lymphadenopathies was based on the infiltration features of plasma cells. The evaluation of IgG and IgG4 as a routine means could exclude the lymph nodes involvement of IgG4-related dieases (IgG4-RD), and whether it was accompanied by autoimmune diseases or multiple-organ diseases, which were of critical evidence for the differential diagnosis. For common lesions of lymphadenopathies, such as Castleman's disease, Kimura's disease, Rosai-Dorfman's disease and dermal lymphadenitis, the expression ratio of IgG4/IgG (>40%) as detected using immunhistochemistry and serum IgG4 levels should be considered as a standard for the possibility of IgG4-RD. The differential diagnosis of multicentric Castleman's diseases and IgG4-RD should be also considered. Conclusions: Infiltration of plasma cells and IgG4-positive plasma cells may be detected in some types of lymphadenopathies and lymphomas in clinicopathological daily practice, but not all of them are related to IgG4-RD. It should be emphasized that the characteristics of plasma cell infiltration and the ratio of IgG4/IgG (>40%) should be considered for further differential diagnosis and avoiding misclassification of lymphadenopathies.

[Preliminary practice of multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases]

Objective: To preliminarily establish the multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases, and to explore its feasibility. Methods: In this prospective study a total of 150 children with hematological and oncological diseases visited immunization clinic of Shanghai Children's Medical Center from March 2017 to August 2018 were enrolled in this study. After establishing the multidisciplinary team, designing vaccination plan, staff training, implementation and quality control, a multidisciplinary immunization clinic was set up and the vaccination plan were implemented. The implementation rate of vaccination immunization, the HBsAb level and serum hepatitis B surface antibody (HBsAb) level before and after treatment, the HBsAb level and serum immunoglobulin G antibody (IgG) levels of measles, mumps, rubella (MMR) before and 6 months after immunization, the vaccine-related adverse reactions were assessed prospectively. Chi-square test or Fisher exact test was used to compare the differences of antibody level. Results: A total of 124 cases had been vaccinated as planned, with a coverage rate of 82.7%. Among these cases, the difference of HBsAb positive rate before and after treatment was significant (62.9% (78/124) vs.13.7% (17/124), χ²= 63.489, P<0.01). In 64 cases that completed three doses of hepatitis B immunization, there was a significant difference in HBsAb positive rate before and 6 months after immunization (6.3% (4/64) vs. 98.4% (63/64), P<0.01). In 40 cases that completed MMR immunization, the IgG antibody positive rate for measles (22.5% (9/40) vs. 82.5% (33/40), χ²=31.746,P<0.01), mumps (22.5% (9/40) vs.82.5% (33/40), χ²=28.872,P<0.01), rubella (25.0% (10/40) vs.62.5% (25/40), χ²=11.429, P<0.01) before and 6 months after immunization were significantly different. Of the 421 doses of immunization, 25 (5.9%) doses reported controlled systemic or local adverse event. Conclusions: The immunization of pediatric patients with hematological and oncological diseases is of great importance. The newly-developed multidisciplinary cooperation immunization model for Chinese children with hematological and oncological diseases is feasible, and the immunization protocol is safe and has a certain effect.

[Clinical characteristics and survival analysis of 15 cases of HIV-negative plasmablastic lymphoma]

目的

分析HIV阴性的浆母细胞淋巴瘤（PBL）患者的临床病理特征及转归。

方法

回顾性分析海军军医大学附属长海医院2013年1月至2019年8月诊断及治疗的15例HIV阴性PBL患者的临床病理资料及随访结果。

结果

15例HIV阴性PBL患者中男8例，女7例，中位年龄59（17~69）岁，均无明确的免疫抑制状态。所有患者均出现结外受累，Ann Arbor-Cotswolds分期Ⅰ、Ⅱ、Ⅲ、Ⅳ期分别为1例（6.7%）、2例（13.3%）、3例（20.0%）、9例（60.0%）。病理形态表现为类似免疫母细胞的大肿瘤细胞弥漫性增生，免疫组化示肿瘤细胞主要表达浆细胞标志CD38、CD138、Mum-1，B细胞标志CD20、CD10、PAX-5、BCL-6少见，Ki-67中位数为80%（70%~90%）。3例患者行EBER原位杂交检测，1例阳性。15例患者均接受化疗，80%（12/15）联合硼替佐米作为一线治疗。最佳疗效6例完全缓解（其中2例分别于治疗后4.9和26.1个月疾病进展），2例部分缓解（分别于治疗后3.0和6.8个月疾病进展），4例疾病进展，3例无法评估。中位随访时间30.3（4.8~61.1）个月，11例患者中位无进展生存（PFS）期6.8（95%CI 2.5~11.1）个月，预计3年PFS率为21.2%（95%CI 1.4%~56.8%）。所有患者中位总生存（OS）期为17.9（95%CI 5.6~30.2）个月，预计3年OS率为38.5%（95%CI 12.0%~65.0%）。

结论

HIV阴性PBL侵袭性强，结外受累常见，多数患者诊断时分期较晚。通过以硼替佐米为基础的强化疗方案序贯自体造血干细胞移植可望获得长期生存。

[The 472nd case: dyspnea, pulmonary shadows, abnormalities of whole blood cells]

A 54-year-old man was admitted to respiratory department with chief complaints of recurrent cough and dyspnea. Chest imaging showed multiple patchy shadows and interstitial changes. Evidence of infectious diseases was not definite, and antibiotic treatments were not effective. In the meantime, myelodysplasia syndrome was diagnosed with pancytopenia. The pathologic findings of transbronchoscopic lung biopsyshowed chronic inflammatory interstitial changes, suggesting a clinical diagnosis of organizing pneumonia. After glucocorticoids treatment, his condition aggravated. The second percutaneous lung biopsy showed the infiltration of a large number of neutrophils. Therefore, the final diagnosis of myelodysplasia syndrome with Sweet syndrome was made. Then glucocorticoids and supportive treatment were given This case may improve physicians' understanding of myelodysplasia syndrome complicated with Sweet syndrome.

[Angioimmunoblastic T-cell lymphoma: histopathological grading and prognosis]

Objective: To investigate the histological features and prognostic factors of angioimmunoblastic T-cell lymphoma (AITL). Methods: The pathological data of 62 patients with AITL with complete follow-up information were retrospectively collected and analyzed from Changhai Hospital during September 2012 and September 2017. Histological and immunohistochemical (IHC) examination, in situ hybridization (ISH), and single nucleotide polymorphisms (SNP) gene mutation analysis were done. Subgroup evaluation with histology, IHC, ISH, SNP gene mutation, and association with clinical progression were performed. Results: The cohort included 62 cases of AITL, including 46 males and 16 females patients, with a median age of 64 years. Follicular dendritic cells (FDC) area showed significantly expansion (≥30%) in 40 cases; increased plasma cells (≥10%) was seen in 37 cases; B cells were distributed around blood vessels in 37 cases; and increased p53 mutation positive cells (≥40%) were seen in 39 cases; high Ki-67 index (≥40%) was seen in 39 cases; RHOA mutation was seen in 19 cases; TET2 mutation was seen in 9 cases. Overall survival analysis showed these factors were significantly correlated with tumor prognosis (P<0.05). Multivariate analysis showed that CD38 positive cells<10%, Ki-67≥40%, RHOA and TET2 mutations were risk factors associated with overall survival. Conclusions: AITL could be divided into two different prognostic groups, low-grade and high-grade, with statistically significance outcome, based on the FDC area expansion, degree of plasma cell proliferation, B cells distribution pattern combined with gene mutations and clinical progression. Low-grade malignant group progresses slowly, and high-grade malignant group is highly invasive.

[Rosai-Dorfman disease: a clinicopathologic analysis and whole exome sequencing in 23 cases]

目的

分析Rosai-Dorfman disease（RDD）的临床病理特征，利用全基因组外显子测序探讨RDD的发病机制。

方法

回顾性分析第二军医大学附属长海医院、长征医院2010年1月至2018年7月收治的23例RDD患者临床病理资料，并对9例患者石蜡包埋组织标本进行了全基因组外显子测序。

结果

23例RDD患者中位年龄47（10~79）岁，19例为结外型，3例为淋巴结型，1例为混合型。所有患者均接受了手术切除病灶，19例患者中位随访24（1~67）个月，均无复发。病理形态主要表现为淋巴结窦内或结外组织中组织细胞增生伴有噬淋巴细胞现象，免疫组化示组织细胞表达S100、CD68、CD163，不表达CD1a。全基因组外显子测序发现mTOR、KMT2D和NOTCH1基因突变。

结论

mTOR、KMT2D和NOTCH1基因突变可能参与了RDD的发病机制，其临床意义仍需要进一步研究。

A novel nude mice model of human extranodal nasal type NK/T-cell lymphoma

A novel nude mice model of human extranodal nasal type NK/T-cell lymphoma was established by subcutaneously implanting the sample taken from the patient with secondary extranodal nasal type NK/T-cell lymphoma of the stomach into the right axillary region of a BALB/c (nu/nu) nude mouse. This model had been successfully transplanted in vivo for thirty-two generations with a stable growth cycle. The survival rates of both resuscitation and transplantation were 100%. Histologically, the tumor cells were medium to large size and arranged in sheets, with a little mesenchyma, and disseminated almost in all passages of the lymphoma-bearing nude mice. Immunologically, the tumor cells were positive for CD56, cytoplasmic CD3, granzyme B or TIA-1 and LMP1, sometimes for CD8 but negative for surface CD3, CD7, CD20 and CD1a. EBER1/2 was found. No T-cell receptor gamma gene rearrangement was detected in the transplanted tumors. Furthermore, both human sequencing-tagged sites SY14 and Y chromosome were detected by PCR or fluorescent in situ hybridization, respectively, in the transplanted tumor. The transplanted tumor in this novel nude mice model maintained the essential features of human extranodal nasal type NK/T-cell lymphoma, and it would be an ideal tool in vivo for further research of the tumor.

Retrieval of chlorophyll from remote-sensing reflectance in the china seas

The East China Sea is a typical case 2 water environment, where concentrations of phytoplankton pigments, suspended matter, and chromophoric dissolved organic matter (CDOM) are all higher than those in the open oceans, because of the discharge from the Yangtze River and the Yellow River. By using a hyperspectral semianalytical model, we simulated a set of remote-sensing reflectance for a variety of chlorophyll, suspended matter, and CDOM concentrations. From this simulated data set, a new algorithm for the retrieval of chlorophyll concentration from remote-sensing reflectance is proposed. For this method, we took into account the 682-nm spectral channel in addition to the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) channels. When this algorithm was applied to a field data set, the chlorophyll concentrations retrieved through the new algorithm were consistent with field measurements to within a small error of 18%, in contrast with that of 147% between the SeaWiFS ocean chlorophyll 2 algorithm and the in situ observation.

Downregulation of ventricular contractile function during early ischemia is flow but not pressure dependent

The mechanism responsible for the abrupt fall in myocardial contractile function following coronary artery obstruction is unknown. The "vascular collapse theory" hypothesizes that the fall in coronary perfusion pressure after coronary artery obstruction is responsible for contractile failure during early ischemia. To test the role of vascular collapse in downregulating myocardial contractile force at the onset of ischemia, coronary flow of isolated rat hearts was abruptly decreased by 50, 70, 85, and 100% of baseline, and subsequent changes in coronary perfusion pressure and ventricular function were recorded at 0.5-s intervals. At 1.5 s after flow reductions ranging from 50 to 100%, decreases in contractile function did not differ, although perfusion pressure varied significantly from 45 +/- 1 to 20 +/- 2 mmHg. When function fell to 50% of baseline, perfusion pressures ranged from 35 +/- 0.5 to 2.5 +/- 1 mmHg for flow reductions ranging from 50 to 100%. Identical contractile function at widely differing coronary perfusion pressures is incompatible with the vascular collapse theory.

Correlation between myocardial contractile force and cytosolic inorganic phosphate during early ischemia

To test the role of inorganic phosphate (Pi) in downregulation of myocardial contractile force at the onset of ischemia, Pi of rat hearts was determined with 31P nuclear magnetic resonance spectroscopy. Forty cycles of brief hypoperfusion (30% of baseline flow for 33 s) were used to achieve a time resolution of 0.512 s for comparing dynamic changes in Pi and contractile force. Initial control values of left ventricular developed pressure (LVP), heart rate, and oxygen consumption were 136 +/- 11 mmHg, 236 +/- 4 beats/min, and 95 +/- 3 microl O2 x min(-1) x g(-1); these values were unchanged at the end of the experiment. During the first 10 s of hypoperfusion, Pi increased at a rate (percentage of the total observed change) faster than the decrease in LVP; Pi and LVP then changed at the same rate during the remainder of the hypoperfusion. ADP did not change in advance of LVP. Intracellular pH did not change. The results indicate that Pi plays an important role in initiating the downregulation of myocardial contractile force at the onset of ischemia. Perfusion pressure also declined faster than LVP at the onset of ischemia, indicating potential importance of vascular collapse in contractile downregulation during early ischemia.

Inorganic phosphate as regulator of adenosine formation in isolated guinea pig hearts

This study evaluated cytosolic P(i) as an independent regulator of cardiac adenosine formation by dissociating changes in P(i) from changes in AMP and ADP. Myocardial high-energy phosphates (HEP), measured by (31)P nuclear magnetic resonance spectroscopy, were depleted acutely by perfusing isolated guinea pig hearts with 2-deoxyglucose (2-DG), and the effects of 2-DG were compared with a norepinephrine infusion producing similar changes in HEP. 2-DG treatment resulted in lower adenosine release (R(ado)) (54 +/- 18 vs. 622 +/- 199 pmol x min(-1) x g(-1)) and P(i) concentration ([P(i)]) (0.5 +/- 0.1 vs. 6.0 +/- 0.9 mM) than norepinephrine despite similar AMP concentration ([AMP]). Chronic phosphocreatine depletion produced by beta-guanidinopropionic acid feeding also reduced R(ado) and P(i) during hypoxia. Replacement of perfusate glucose and pyruvate with acetate increased R(ado) (from 39 +/- 12 to 356 +/- 100 pmol x min(-1) x g(-1)) and [P(i)] (from 2.0 +/- 0.5 to 5.1 +/- 0.6 mM) with no change in cytosolic [AMP]. Adenosine kinase isolated from guinea pig hearts was inhibited by [P(i)] values seen during hypoxia or hypoperfusion. We conclude that cytosolic [P(i)] can be an important regulator of cardiac adenosine formation through inhibition of adenosine kinase.

Adenosine receptor blockade enhance glycolysis in hypoperfused guinea-pig myocardium

OBJECTIVE

This study tested the hypothesis that endogenous adenosine depresses anaerobic glycolysis in preischaemic and moderately ischaemic myocardium.

METHODS

Isolated, working guinea-pig hearts, perfused with glucose-fortified Krebs-Henseleit buffer, were subjected to 15 min mild hypoperfusion (coronary flow 60% of baseline) followed by 10 min ischaemia (coronary flow 20% of baseline). Adenosine A1 receptors were blocked with 8-p-sulfophenyl theophylline (8-SPT; 20 microM). Glucose oxidation and lactate production from exogenous glucose were assessed from 14CO2 and [14C]lactate formation, respectively, from [U-14C]glucose. Energy metabolites, glycolytic intermediates and glycogen were measured in extracts of stop-frozen preischaemic, mildly hypoperfused and ischaemic myocardium.

RESULTS

Adenosine receptor blockade did not affect left ventricular function assessed from heart rate x pressure product and pressure x volume work although coronary flow was slightly reduced. Adenosine receptor blockade increased glucose uptake (P < 0.05) by 100% during preischaemia and by 74% during mild hypoperfusion, and increased lactate production from exogenous glucose (P < 0.05) by 89% during preischaemia and fourfold during mild hypoperfusion, but did not stimulate glucose oxidation under any condition. Glycogen degradation was not increased by adenosine receptor blockade during ischaemia. Crossover plots of glycolytic intermediates revealed that phosphofructokinase was activated by adenosine receptor blockade at all three levels of perfusion.

CONCLUSION

Endogenous adenosine attenuates anaerobic glycolysis in normally perfused, hypoperfused and ischaemic myocardium by blunting phosphofructokinase activity; this effect is mediated by adenosine A1 receptors.

[A study on combination therapy of Western and traditional Chinese medicine of acute viral myocarditis]

To investigate the combination therapy of Western and traditional Chinese medicine on treatment of acute viral myocarditis, 48 patients were randomly divided into 2 groups. The 1st group consisted of 30 patients, receiving the combination therapy of Western and traditional Chinese medicine, including Astragalus membranaceus, taurine, coenzyme Q10 and antiarrhythmics, while the 2nd group consisted of 18 patients, receiving the conventional therapy, including glucose-insulin-potassium (GIK), coenzyme Q10 and also antiarrhythmics.

RESULTS

The efficacy of combination therapy of western and traditional Chinese medicine was better than that of conventional therapy in improving the clinical manifestation, negative converting positive EVsRNA in peripheral leukocytes and controlling the premature beats.

CONCLUSION

The combination therapy of western and traditional Chinese medicine was an effective method in treating acute viral myocarditis.

Effects of nimodipine on acute cerebral ischemia and reperfusion injury of rats

AIM

To study the effect of nimodipine (Nim) on ischemic cerebral damage.

METHODS

The four-vessel occlusion method was performed on rats. Monoamines were measured by fluorospectrophotometry.

RESULTS

Intraperitoneal injection of Nim 0.75 and 1.5 mg.kg-1 quickened the recovery of EEG changes to 19 +/- 3 and 17 +/- 4 min (P < 0.01), respectively. Nim reduced the decreases of monoamines (NE, DA, 5-HT, and 5-HIAA) contents after 30-min cerebral ischemia and 1-h reperfusion.

CONCLUSION

Nim protects the brain from ischemic damage.

Adenosine formation during hypoxia in isolated hearts: effect of adrenergic blockade

Adrenergic receptor blockade has been reported to decrease cardiac adenosine formation and release during hypoxia. We wished to determine whether this occurs by an improvement in the energy supply/demand ratio. Isolated guinea pig hearts were perfused at a constant pressure of 50 mm Hg. Hypoxia (30% O2) was maintained for 20 min while adenosine release and venous PO2 were measured in the coronary venous effluent. beta-adrenergic blockade with 5 microM atenolol did not change hypoxic adenosine release (Control: 15.6 +/- 2.7, Atenolol: 23.6 +/- 5.7 nmol/g/20 min). Addition of 6 microM phentolamine with atenolol significantly reduced hypoxic adenosine release (4.4 +/- 1.4 nmol/g/20 min, P < 0.05). Atenolol was without hemodynamic effects, but addition of phentolamine reduced left ventricular pressure development, heart rate, and oxygen consumption prior to hypoxia. Atenolol plus phentolamine did not change venous PO2 during hypoxia. Treatment with phenoxybenzamine (1 microM) plus atenolol also reduced adenosine release (7.4 +/- 0.8 nmol/g/20 min). Control experiments and atenolol plus phentolamine experiments were repeated using 31P-NMR to measure high energy phosphates. Adrenergic blockade had no effect on phosphate concentrations during normoxia, but resulted in higher [PCr], lower [P(i)] and higher phosphorylation potentials during hypoxia. Adrenergic blockade also prevented the hypoxia-induced rise in intracellular [H+], [AMP] and [ADP] seen in control hearts. The changes in phosphorylation potential are correlated with similar changes in adenosine release in adrenergically intact hearts. We conclude that the primary effect of adrenergic blockade during hypoxia is a reduction in ATP use due to alpha-receptor blockade. This leads to improved high energy phosphate concentrations during hypoxia and a reduction in adenosine formation.

Adenosine release and high energy phosphates in intact dog hearts during norepinephrine infusion

Cardiac adenosine release is thought to depend on the oxygen supply/demand ratio, and this effect may be mediated by changes in high energy phosphate concentrations. Previous studies supporting this hypothesis have been done primarily in isolated hearts. We tested this hypothesis in intact dog hearts. Anesthetized, open-chest dogs were placed in a 4.7-T magnet where 31P nuclear magnetic resonance spectra were acquired via a surface coil over the heart at 2-minute intervals (60 scans, 2-second interpulse delay). Coronary sinus flow was shunted through a flow probe and returned via a jugular vein. After a control period, intracoronary norepinephrine was infused (12 micrograms/min) for 16 minutes and plasma samples were taken every 5 minutes. The phosphocreatine/ATP peak area ratio was used as an index of high energy phosphate changes. During norepinephrine infusion, arterial pressure, heart rate, coronary sinus flow, oxygen consumption, and adenosine release all increased significantly. Adenosine release peaked at 5 minutes but remained elevated after 15 minutes. There was a transient fall in the phosphocreatine/ATP ratio (9.2 +/- 3.1%, p less than 0.05) during the first 7 minutes, but the ratio returned to control levels by 9 minutes. The oxygen supply/consumption ratio increased after 5 minutes of norepinephrine infusion and then returned to control levels. We conclude that during norepinephrine infusion in vivo, persistent adenosine release can occur with only small transient changes in high energy phosphate concentrations and with no decrease in the oxygen supply/demand ratio.

Adenosine formation and energy status in isolated guinea pig hearts perfused with erythrocytes

The purpose of this study was to examine adenosine release and high-energy phosphate concentrations during norepinephrine (NE) infusion in isolated guinea pig hearts perfused with a physiological salt solution (PSS) containing erythrocytes (RBC). Phosphate concentrations were monitored using 31P-nuclear magnetic resonance spectroscopy while NE was infused at 6 x 10(-10) mol/min. Compared with perfusion with PSS alone, RBC-perfused hearts consumed more oxygen and developed higher left ventricular pressure and first time derivative of left ventricular pressure at lower coronary flow rates. Adenosine release rates were very similar with both perfusates. NE infusion did not produce a decline in ATP concentration ([ATP]) or an increase in calculated [ADP] and [AMP] in RBC-perfused hearts. However, phosphorylation potential ([ATP]/[ADP][Pi]) declined because of increased [Pi]. We conclude that NE infusion does not change adenine nucleotide concentrations in well-oxygenated guinea pig hearts and that changes in nucleotide concentrations are not necessary for increased adenosine release. Phosphorylation potential is a better predictor of adenosine release than any individual nucleotide or phosphate concentration.

Adenosine formation and myocardial energy status during graded hypoxia

Previous studies using hypoperfusion and 2-deoxyglucose infusion have revealed a biphasic relationship between myocardial energy status and adenosine release (RADO). As energy charge ([ATP] + 1/2[ADP])/([ATP] + [ADP] + [AMP]) or phosphorylation potential ([ATP]/[ADP][Pi]) is lowered there is an initial increase in RADO, but RADO declines from peak levels during severe energy depletion. This study examined the hypothesis that the same pattern of RADO exists during graded hypoxia. Isolated guinea-pig hearts were perfused at constant flow and exposed to mild (30% O2) and severe (0% O2) hypoxia in the presence of norepinephrine (NE, 6 x 10(-8) M). Phosphorylation potential and energy charge were determined using 31P-NMR spectroscopy and adenosine release into coronary venous effluent was measured. Graded hypoxia lowered energy charge and phosphorylation potential, and raised RADO. Although severe hypoxia plus NE lowered energy charge and phosphorylation potential to levels equivalent to those associated with decreased RADO during hypoperfusion or 2-deoxyglucose treatment, RADO during severe hypoxia was greater than during mild hypoxia. HCl was infused during severe hypoxia in order to reproduce the low intracellular pH seen during hypoperfusion, but HCl increased RADO rather than decreasing it. We conclude that during hypoxia, RADO does not have a biphasic relationship to phosphorylation potential or energy charge, suggesting that the regulation of adenosine formation cannot be explained solely in terms of these variables. Furthermore, intracellular acidosis is not responsible for inhibiting RADO at low phosphorylation potential and energy charge during hypoperfusion because it has no effect on RADO during severe hypoxia.

Adenosine formation and energy status during hypoperfusion and 2-deoxyglucose infusion

The relationship between adenosine (Ado) formation and cytosolic energy status was studied in isolated guinea pig hearts during hypoperfusion plus norepinephrine infusion (0.6 nmol/min) and in isolated rat hearts during 2-deoxyglucose (2-DG) infusion. 31P nuclear magnetic resonance (31P-NMR) was used to measure phosphate concentrations, and both phosphorylation potential (expressed as [ATP]/[ADP][Pi]) and energy charge [expressed as (([ATP] + 1/2[ADP])/([ATP] + [ADP] + [AMP]))] were calculated as indexes of cytosolic energy status. Both progressive flow reductions and increasing length of exposure to 2-DG led to progressive decreases in energy charge and phosphorylation potential. In both cases, steady-state Ado release first increased then declined despite a continued fall in energy status. Inosine release followed a similar pattern. This biphasic pattern of Ado release vs. energy charge is similar to the pattern seen in in vitro studies of cytosolic 5'-nucleotidase, supporting the hypothesis that Ado formation in vivo is regulated by the influence of energy status on this enzyme. However, Ado release in vivo peaked at an energy charge much higher (0.997) than that observed in vitro (0.60-0.86). It is therefore probable that the inhibition of Ado formation in the perfused heart occurs via factor(s) in addition to energy charge.

Steric course of the N-methylation in the biosynthesis of ergot alkaloids by Claviceps purpurea

Using the chiral methyl group methodology, the methylation step in the biosynthesis of ergot alkaloids catalyzed by the enzyme AdoMet:dimethylallyltryptophan N-methyltransferase was found to proceed with net inversion of methyl group configuration. The enzyme thus conforms to the majority of methyltransferases studied which mediate a direct SN2 transfer of the methyl group from AdoMet to the acceptor nucleophile in a ternary enzyme substrate complex.

[Changes in systolic and diastolic function of reperfused myocardium after short coronary occlusions in conscious dogs]

Mongrel dogs were chronically implanted with sonomicrometer crystals and a high fidelity tip micromanometer to measure ventricular wall thickness (WT) and left ventricular pressure (LVP), respectively. Two weeks after surgical operation, the left circumflex coronary artery was occluded with a hydraulic occluder for 3 minutes in conscious condition. During reperfusion, the hemodynamic parameters and systolic wall thickening recovered to the normal level quickly, while an abnormal thickening phase during early relaxation (extra phase) appeared in the dWT/dt-WT loop (X-axis = WT, Y-axis = dWT/dt) with its pattern different from that during control and ischemic conditions. This kind of pattern of the loop could be observed during hypoxia and during rapid overfilling of coronary artery. It is supposed that some substances, which may be produced in the ischemic myocardium, induced an extra dilation of coronary artery during reperfusion and a rapid overperfusion in the early relaxation phase of the cardiac cycle, leading to the abnormal pattern in the loop.

Phosphorylation potential and adenosine release during norepinephrine infusion in guinea pig heart

This study tested the hypothesis that adenosine released from isolated guinea pig hearts (n = 5) in response to norepinephrine is related to the cellular phosphorylation potential (PP; [ATP]/[ADP][Pi]), where Pi is inorganic phosphate. 31P-nuclear magnetic resonance (NMR) was used to measure the relative concentrations of Pi, phosphocreatine (PCr), and ATP. Hearts were Langendorff perfused with a physiological salt solution containing 0.1 mM Pi. The venous effluent was collected for measurement of adenosine and partial pressure of oxygen (PO2). After a control period, norepinephrine (6 X 10(-8) M) was infused for 20 min during which 31P-NMR spectra and samples of venous effluent were collected every minute. With norepinephrine infusion, PCr decreased rapidly to 72% of control (P less than 0.05) by 8 min and then recovered to 80% of control for the remaining 12 min. ATP fell slowly to 70% of control (P less than 0.01) over 20 min. Pi increased to a peak at 2 min (P less than 0.01), then declined slowly to a steady state (60% of the peak and 3.5 X control) from 8 to 20 min. Adenosine release increased from 11 +/- 6 to a peak of 250 +/- 68 pmol.min-1.g-1 (P less than 0.01) at 7 min and then slowly fell (P less than 0.05) to a steady state of approximately 110 pmol.min-1.g-1 (P less than 0.01 vs. control) from 10 to 20 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Multichannel frequency-domain image processor

The theory and experiments for a multichannel optical system for pseudocolor encoding of images are presented. Spatial-frequency pseudocolor encoding is accomplished by spatial filtering different-colored spectra in different channels. Density pseudocolor encoding is accomplished by the incoherent addition of three primary color images: a contrast-reversal image in one color, a positive image in the second color, and a contrast half-reversal image in the third color. This is a simple, real-time technique. It has no resolution loss that is due to the use of gratings or halftone screens, and the optical system does not require Fourier-transform lenses with large relative apertures.