Venous drainage in the reverse forearm flap

Venograms were performed in three cases of reverse forearm flap. The "crossover pattern" of the communicating branches between the two venae comitantes and the "bypass pattern" of the collateral branches of each vein have been demonstrated. These factors may explain the reverse drainage of venous blood, even though the valves of the vein are intact. Notably, the cephalic vein also shows a good communication with the deep venous system. Thus it can contribute another route for venous drainage in this flap.

Suppression of ultraviolet irradiation-induced apoptosis by overexpression of focal adhesion kinase in Madin-Darby canine kidney cells

Focal adhesion kinase (FAK) has been implicated to play a role in suppression of apoptosis. In this study, we have demonstrated that UV irradiation induced cleavage of FAK and two of its interacting proteins Src and p130(Cas) in Madin-Darby canine kidney cells, concomitant with an increase in cell death. The cleavage of these proteins upon UV irradiation was completely inhibited by ZVAD-FMK, a broad range inhibitor of caspases, and apparently delayed by Bcl2 overexpression. To examine if FAK plays a role in suppressing UV-induced apoptosis, stable Madin-Darby canine kidney cell lines overexpressing FAK were established. Our results showed that a marked (30-40%) increase in cell survival upon UV irradiation was achieved by this strategy. In our efforts to determine the mechanism by which FAK transduces survival signals to the downstream, we found that a FAK mutant deficient in binding to phosphatidylinositol 3-kinase failed to promote cell survival. Moreover, the expression of the Src homology 3 domain of p130(Cas), which competed with endogenous p130(Cas) for FAK binding, abrogated the FAK-promoted cell survival. Together, these results suggest that the integrity of FAK and its binding to phosphatidylinositol 3-kinase and p130(Cas) are required for FAK to exert its antiapoptotic function.

A novel approach based on computerized image analysis for traditional Chinese medical diagnosis of the tongue

This research is aimed at building a computerized tongue examination system (CTES) based on computerized image analysis for the purpose of quantizing the tongue properties in traditional Chinese medical diagnosis. The chromatic algorithm is developed to identify the colors of the tongue and the thickness of its coating. The textural algorithm is used to detect the grimy coating. CTES is shown to be significantly consistent within itself with P > 0.05 using the Hotelling multivariate statistical test. The overall rate of correctness for CTES to identify the colors of tongue, verifying the thickness of its coating and detecting of any grimy coating exceeds 86%. Therefore, the CTES is helpful to provide the physicians a systematic and objective diagnostic standard for the tongue diagnosis in the clinical practice and research.

X-ray diffraction studies of fibers and crystals of deoxygenated sickle cell hemoglobin

Paracrystalline fibers of deoxygenated sickle hemoglobin in erythrocytes or concentrated solutions exhibit a phase transformation to a fully crystalline state. X-ray diffraction patterns of the fiber and crystallites are similar except in two respects: the equatorial spacings of the fibers suggest that they pack into a square lattice with a = 220 A, whereas those of the crystals can be indexed on the basis of a net of 187 A by 54 A, and the second-order near-meridional reflections are strong on the fiber pattern but weak on that of the crystallites. The crystallites are isomorphous with single crystals grown in polyethylene glycol solution at pH 4.5 whole structure has been determined at near-atomic resolution (Wishner, B.C., Ward, K.B. Lattmen, E.E. & Lowve, W.E. (1975) J. Mol. Biol. 98, 179-194). Double filaments of molecules with an axial repeat of 64 A comprise the basic unit of both the crystal and fiber structures. Each filament of the pair is translated with respect to its neighbor by half a molecular diameter along the fiber axis. The two filaments are held together by contacts made by Val 6beta in the molecules of one strand with hydrophobic side chains of the molecule in the neighboring strand. This interaction is probably the cause of the aggregation of filaments into fibers that leads to the sickling of erythrocytes.

Defective phagocytosis, decreased tumour necrosis factor-alpha production, and lymphocyte hyporesponsiveness predispose patients with systemic lupus erythematosus to infections

Twenty-three patients with systemic lupus erythematosus (SLE) were studied in order to understand the mechanism of increased susceptibility to infection in SLE patients. We found that phagocytosis by polymorphonuclear leucocytes (PMN) was significantly defective in untreated (24.2 +/- 3.1%) and immunosuppressant-treated SLE patients (30.0 +/- 3.6%) compared with normals (47.9 +/- 0.6%), while the generation of superoxide anion radicals was normal. The defective phagocytosis in SLE could be increased by human recombinant tumour necrosis factor alpha (TNF-alpha). However, the percentages of phagocytosis in SLE before and after TNF-alpha stimulation were 56.6% and 60.7% of the normal values. This indicates that certain populations of PMN in SLE are not only defective as regards phagocytosis but also unresponsive to TNF-alpha stimulation. In an ELISA, TNF-alpha production by phorbol myristate acetate (PMA)-stimulated mononuclear cells from SLE patients was significantly decreased (181.4 +/- 22.7 pg/ml vs. 533.0 +/- 81.9 pg/ml, p = 0.002). In addition, the percentage of phytohaemagglutinin (PHA)-stimulated mononuclear cells in S phase in the cell cycle was deficient in patients with SLE (17.2 +/- 1.8% vs. 29.7 +/- 2.9%, p less than 0.001). These results lead us to propose that defective PMN in spontaneous and TNF-alpha-induced phagocytosis, decreased production of TNF-alpha, and lymphocyte hyporesponsiveness predispose patients with SLE to infections.

Molecular genetics of β-thalassemia: A narrative review

ABSTRACT

β-thalassemia is a hereditary hematological disease caused by over 350 mutations in the β-globin gene (HBB). Identifying the genetic variants affecting fetal hemoglobin (HbF) production combined with the α-globin genotype provides some prediction of disease severity for β-thalassemia. However, the generation of an additive composite genetic risk score predicts prognosis, and guide management requires a larger panel of genetic modifiers yet to be discovered.Presently, using data from prior clinical trials guides the design of further research and academic studies based on gene augmentation, while fundamental insights into globin switching and new technology developments have inspired the investigation of novel gene therapy approaches.Genetic studies have successfully characterized the causal variants and pathways involved in HbF regulation, providing novel therapeutic targets for HbF reactivation. In addition to these HBB mutation-independent strategies involving HbF synthesis de-repression, the expanding genome editing toolkit provides increased accuracy to HBB mutation-specific strategies encompassing adult hemoglobin restoration for personalized treatment of hemoglobinopathies. Allogeneic hematopoietic stem cell transplantation was, until very recently, the curative option available for patients with transfusion-dependent β-thalassemia. Gene therapy currently represents a novel therapeutic promise after many years of extensive preclinical research to optimize gene transfer protocols.We summarize the current state of developments in the molecular genetics of β-thalassemia over the last decade, including the mechanisms associated with ineffective erythropoiesis, which have also provided valid therapeutic targets, some of which have been shown as a proof-of-concept.

Repeated ingestion of grapefruit juice does not alter clozapine's steady-state plasma levels, effectiveness, and tolerability

BACKGROUND

Grapefruit juice can inhibit the gastrointestinal activity of cytochrome P450 (CYP) 3A4, while its effect on CYP1A2 remains controversial. Several grapefruit juice bioflavonoids also modulate the activity of the drug transporter P-glycoprotein in the gut and in the blood-brain barrier. Both CYP1A2 and CYP3A4 are involved in clozapine metabolism. This study investigated the effects of repeated ingestion of grapefruit juice on multiple-dose pharmacokinetics and pharmacodynamics of clozapine in schizophrenic patients.

METHOD

Clozapine therapy was initiated for fifteen treatment-resistant schizophrenic inpatients (DSM-IV criteria). The doses were individually titrated from day -35 to day -15 and then kept unchanged from day -14 to day 49. Regular-strength grapefruit juice (250 mL) was coadministered b.i.d. with each clozapine dose from day 15 to day 28. Plasma levels of clozapine and its main metabolites (norclozapine and clozapine N-oxide) were obtained, and clinical efficacy and safety assessments were completed prior to juice administration (days 0, 7, and 14), during the coadministration (days 17, 21, and 28), and after cessation of the juice (days 35, 42, and 49).

RESULTS

After reaching steady states, plasma concentrations of clozapine and its metabolites and Positive and Negative Syndrome Scale scores were not significantly altered by the effect of grapefruit juice ingestion. The Clinical Global Impressions scale scores, Calgary Depression Scale scores, and side effect profiles (by the Extrapyramidal Symptom Rating Scale, the UKU Side Effect Rating Scale, and thorough examinations including electrocardiography and electroencephalography) also remained constant during the study.

CONCLUSION

Consumption of regular-strength grapefruit juice, 250 mL b.i.d., for 14 days did not significantly impact clozapine metabolism, clinical efficacy, or tolerability. One reason is that enzymes other than CYP3A4 also mediate clozapine disposition. Also, grapefruit juice inhibits CYP3A4 in the gut, but not in the liver. The preliminary results also suggest that clozapine is unlikely to be a P-glycoprotein substrate. Further rigorous studies are necessary to reconfirm these findings.

Giant aneurysm of main pulmonary artery

Aneurysm of the main pulmonary artery is an extremely rare entity. The first successful repair of an aneurysm of the main pulmonary artery was reported in 1971. Since then, surgical correction of the aneurysm of main pulmonary artery has been undertaken in only 6 cases. A thorough survey of the literature, including autopsy cases, medical cases, and surgical cases, shows the aneurysm in the present case to be one of the largest.

Eugenodilol: a third-generation beta-adrenoceptor blocker, derived from eugenol, with alpha-adrenoceptor blocking and beta2-adrenoceptor agonist-associated vasorelaxant activities

Eugenodilol, derived from natural eugenol, was first investigated with in vivo and in vitro models. In our in vivo study, eugenodilol (0.5, 1.0, and 1.5 mg/kg, i.v.) produced dose-dependent hypotensive and bradycardic responses in pentobarbital-anesthetized Wistar rats. Eugenodilol also inhibited the tachycardia and arterial pressor effects induced by (-)isoproterenol and phenylephrine, respectively. In our in vitro study, eugenodilol competitively antagonized (-)isoproterenol-induced positive inotropic and chronotropic effects and tracheal-relaxation responses on isolated guinea pig tissues in a concentration-dependent manner. The apparent pA2 values were 7.88+/-0.12 for right atria, 7.52+/-0.05 for left atria, and 7.33+/-0.15 for trachea, indicating that eugenodilol was a nonselective beta-adrenoceptor blocker. In thoracic aorta experiments, the apparent pA2 values of alpha-adrenoceptor blockade were 7.05+/-0.25 and 6.87+/-0.08 for eugenodilol and labetalol, respectively. In addition, eugenodilol produced cumulative relaxation responses on isolated guinea pig tracheal strips. The effects were competitively antagonized by ICI 118,551 (10(-8)-10(-6) M), a relatively selective beta2-adrenoceptor antagonist. In the radioligand-binding assay, the Ki values of [3H]CGP-12177 binding to rat ventricle and lung membranes were 9.72 and 48.29 nM, respectively, and the value of [3H]prazosin binding to rat brain membrane was 38.72 nM. These results further confirmed the alpha/beta-adrenoceptors-blocking activities of eugenodilol reported in the functional studies. We conclude that eugenodilol is a novel third-generation beta-adrenoceptor blocker with ancillary blocking activity at alpha-adrenoceptors and weak sympathomimetic activity at beta2-adrenoceptors.

Assessment of cerebral autoregulation using time-domain cross-correlation analysis

Time domain cross-correlation analysis of pre-filtered mean arterial blood pressure (MABP) and mean cerebral blood flow velocity (MCBFV) was applied to assess the cerebral autoregulation (CA). Beat-to-beat time series of spontaneous arterial blood pressure and cerebral blood flow velocity were obtained from 13 young normal volunteers with the Finapres device and the transcranial Doppler for periods of approximately 5 min in the supine position. Cross-correlation functions (CCFs) were estimated using a 64 beat wide moving window. Mean CCF patterns were obtained for each subject and for the entire population. The MABP and MCBFV signals were bandpass filtered in the very low-frequency range (VLF, 0.015-0.07 Hz), low-frequency range (LF, 0.07-0.15 Hz) and high-frequency range (HF, 0.15-0.40 Hz) before applying CCF for the purpose of studying the effect of different bandwidths on the resulting mean CCFs. Results revealed that the corresponding time lags of the peak values of the MABP-MCBFV CCFs increased significantly between the LF and HF frequency ranges (LF: -1.20+/-0.91 s, HF: -0.07+/-0.42 s,p < 0.001; paired sign test). The left-shift (negative lag) of the CCF peak between MABP and MCBFV is a result of the phase-lead property. The increasing time lag of the CCF peak indicated evidence of the autoregulatory disturbance. The CCF of pre-filtered spontaneous MABP and MCBFV could be a useful tool to estimate the CA dynamic response.

Large Collective Lamb Shift of Two Distant Superconducting Artificial Atoms

Virtual photons can mediate interaction between atoms, resulting in an energy shift known as a collective Lamb shift. Observing the collective Lamb shift is challenging, since it can be obscured by radiative decay and direct atom-atom interactions. Here, we place two superconducting qubits in a transmission line terminated by a mirror, which suppresses decay. We measure a collective Lamb shift reaching 0.8% of the qubit transition frequency and twice the transition linewidth. We also show that the qubits can interact via the transmission line even if one of them does not decay into it.

Persistent fifth aortic arch: an ignored and underestimated disease

We report two unique cases of persistent fifth aortic arch with a systemic-to-pulmonary connection. All previously reported cases with such a connection in the literature have either been cases of pulmonary atresia or an aortic arch anomaly, and the existence of a fifth aortic arch was a benefit to the underlying great vessel anomaly. However, our two cases did not have this associated great vessel anomaly, and the fifth arch resulted in a large left-to-right shunt with severe pulmonary hypertension and heart failure. The first case was misdiagnosed preoperatively; an accurate diagnosis was made after cardiac surgery. Because of its rarity and complexity, a persistent fifth aortic arch is often ignored and misdiagnosed.

Apoptosis in nasopharyngeal carcinoma as related to histopathological characteristics and clinical stage

AIMS

We investigated the significance of apoptosis, using the terminal deoxynucleotidyl transferase mediated dUTP-digoxigenin nick end-labelling method, in nasopharyngeal carcinoma biopsy samples.

METHODS AND RESULTS

The apoptotic index (AI) in 50 nasopharyngeal carcinomas was compared with various histopathological features and clinical stage. Also, the AI was correlated with p53, bcl-2 and Ki67 expression by immunohistochemistry. In histopathological studies, the AI was significantly higher in mixed cellular type (MC) than in keratizing squamous cell type (KS) and spindle cell type (SC) (P < 0.001) which worsens prognosis. In tumour stage analyses, AI was higher in early stage (stage 2 and 3) than in high stage (stage 4). In addition, there was a significant correlation between the AI and p53 expression (P < 0.001) but not with proliferative activity (P = 0.15). In NPC containing p53 protein positive tumour cells, there was a significantly higher apoptotic rate.

CONCLUSIONS

These findings indicate that apoptosis is related to type and stage of nasopharyngeal carcinoma. They also confirm the role of p53 in regulating tumour apoptosis.

Self-organizing arterial pressure pulse classification using neural networks: theoretical considerations and clinical applicability

A self-organizing classification system for the arterial pressure pulse based on the ART2 (adaptive resonance theory) network was developed. The system consists of a preprocessor and an ART2 recognition network. The preprocessor removes the arterial pressure pulse servo component signals from Finapres, detects the systolic pressure points and divides the acquired signals into minimal cardiac cycles. The ART2 network input is the minimal cardiac cycle detected by the preprocessor. The classification results can be used to assist physicians in evaluating the signs of abnormal and normal autonomic control and has shown its clinical applicability for the examination of the autonomic nervous system.

Uneven myocardial hypothermia among cardiac chambers during hypothermic myocardial preservation

During the development of methods to protect the heart from ischaemic injury, attention has been focused on protection of the left ventricle. In an attempt to assess right heart preservation. 55 consecutive patients undergoing open heart surgery were studied. Mean aortic cross-clamp time was 59.3 +/- 29.4 min. Temperature probes were inserted into the right atrium (RA), right ventricle (RV), and left ventricle (LV). During cardioplegia, the mean myocardial temperatures of RA, RV and LV were 19.1 degrees +/- 4.1 degrees C, 12.7 degrees +/- 4.8 degrees C and 7.3 degrees +/- 3.4 degrees C, respectively. Of the LV temperature measurements, 67.2% were 10 degrees C or lower. By contrast, 94.1% of RA measurements and 58.5% of RV measurements were above 10 degrees C. The inhomogeneity of chamber temperatures was observed irrespective of the patient's disease or age and whether the atrium or right ventricle were open or not. Hearts with mitral regurgitation (MR), in contrast to mitral stenosis and stenoinsufficiency, had higher LV temperatures, similar to those in the RV. We conclude that there is uneven hypothermia among the three cardiac chambers during hypothermic cardioplegic arrest, regardless of disease states except MR and regardless of age and procedure performed.

Influencing factors and ambulation outcome in patients with dual disabilities of hemiplegia and amputation

OBJECTIVE

To determine the ambulatory outcome and predictive factors of successful ambulation training in patients with both hemiplegia and lower extremity amputation.

DESIGN

A retrospective study.

SETTING

A rehabilitation center of a university hospital.

PATIENTS

Twenty-three patients with dual disabilities consecutively admitted to the rehabilitation center from 1984 to 1994.

MAIN OUTCOME MEASURES

Ambulatory outcome was measured using physical therapists' and physicians' notes at discharge or the last available clinical visit. Ambulation ability was graded as community and noncommunity ambulation, which included indoor ambulation and nonambulation. Several clinical features were reviewed to assess their association with ambulation outcome.

RESULTS

About two thirds of the 23 patients could be trained to be ambulatory: 10 (43.8%) achieved community ambulation and 5 (21.7%) achieved indoor ambulation. Of the clinical factors, only mental status showed a statistically significant association with good ambulation outcome (p<.05). When odds ratios were considered, several factors, including mild motor involvement, transtibial amputation, amputation before cerebrovascular accident, age younger than 60 years, and the presence of ipsilateral hemiplegia and amputation, showed trends toward association with increased ambulation achievement, although these associations were not statistically significant.

CONCLUSION

Impaired mental status seemed to be the most influential negative predictive factor of achieving community ambulation. If subjects with dual disabilities are properly selected, satisfactory results of ambulation training will be obtained.

Pharmacological effects of an aldehyde type alpha/beta-adrenoceptor blocking agent with vasodilating properties

KMUP 880723 (0.5, 1.0, and 3.0 mg/kg, iv) produced dose-dependent hypotensive and bradycardia responses in pentobarbital-anesthetized Wistar rats. KMUP 880723 (1.0 mg/kg, iv) also markedly inhibited both the tachycardia effects induced by (-)isoproterenol and arterial pressor responses induced by phenylephrine. In the isolated Wistar rat right atria, left atria, and guinea pig tracheal strips, KMUP 880723 competitively antagonized the (-)isoproterenol-induced positive chronotropic effects, inotropic effects, and tracheal relaxation effects in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol suggested that KMUP 880723 was a beta(1)/beta(2)-adrenoceptor competitive antagonist. The apparent pA(2) values were 6.89+/-0.10 in the right atria, 7.02+/-0.09 in the left atria, and 6.59+/-0.11 in the trachea, indicating that KMUP 880723 was a nonselective beta-adrenoceptor blocker. In thoracic aorta experiments, KMUP 880723 also produced a competitive antagonism of norepinephrine-induced contraction with a pA(2) value of 7.14+/-0.06. In isolated rat thoracic aorta, KMUP 880723 more potently relaxed the contractions induced by norepinephrine (3 x 10(-6) M) than those by high K(+) (75 mM). In the radioligand-binding assay, the pK(i) values of [3H]CGP-12177 binding to rat ventricle and lung membranes were 6.56 and 6.40, respectively, and the value of [3H]prazosin binding to rat brain membranes was 6.66. These results further confirmed the alpha/beta-adrenoceptor blocking activities of KMUP 880723 reported in the functional studies. We conclude that KMUP 880723 is a nonselective beta-adrenoceptor antagonist with alpha-adrenoceptor blocking-associated vasorelaxant activity.

Highly efficient beamline and spectrometer for inelastic soft X-ray scattering at high resolution

The design, construction and commissioning of a beamline and spectrometer for inelastic soft X-ray scattering at high resolution in a highly efficient system are presented. Based on the energy-compensation principle of grating dispersion, the design of the monochromator-spectrometer system greatly enhances the efficiency of measurement of inelastic soft X-rays scattering. Comprising two bendable gratings, the set-up effectively diminishes the defocus and coma aberrations. At commissioning, this system showed results of spin-flip, d-d and charge-transfer excitations of NiO. These results are consistent with published results but exhibit improved spectral resolution and increased efficiency of measurement. The best energy resolution of the set-up in terms of full width at half-maximum is 108 meV at an incident photon energy tuned about the Ni L3-edge.

Objective auscultation for traditional chinese medical diagnosis using novel acoustic parameters

The goal of this work is to propose novel acoustic parameters of voice for the purpose of providing a quantitative analysis of auscultation in traditional Chinese medical diagnosis. There is rare amount of available literature related to this topic. Four novel acoustic parameters, the average number of zero-crossings, the variations in local peaks and valleys, the variations in first and second formant frequencies, and the spectral energy ratio, are presented to analyze and identify the characteristics among non-vacuity, qi-vacuity, and yin-vacuity subjects. Among these acoustic parameters, two temporal parameters, the average number of zero-crossings and the variations in local peaks and valleys, outperformed other parameters in classifying both non-vacuity and deficient subjects. The spectral energy ratio was adequate for the classification between qi-vacuity and yin-vacuity patients. This research is a first step in an ongoing effort to modernize the auscultation in traditional Chinese medical diagnosis.

Gene transfer via pollen-tube pathway for anti-fusarium wilt in watermelon

In order to obtain transgenic fusarium wilt resistant watermelon plants, squash DNA was introduced into the ovaries of watermelon plants via the pollen-tube pathway. The introduction of foreign genes into ovaries was accomplished using co-transformation with the CaMV35S-GUS as a marker. Transformed watermelon plants contained integrated copies of the GUS activity and the seeds of transformed progeny produced a blue color when stained with 5-bromo-4-chloro-3-indolyl glucuronide, whereas seeds from untransformed control plants did not. Of 200 transformed seedlings, ten were wilt resistant. The presence of the GUS activity in the genome of stable transgenic seedlings was confirmed by Southern blot analysis. Furthermore, the generation of random amplified polymorphic DNA (RAPD) fingerprints using primers with embedded restriction sites showed amplification products unique to these transgenic plants. Primers OPA-1 and OPA-9 gave distinct band patterns of genomic DNA using the polymerase chain reaction.

Lack of CYP3A4 inhibition by grapefruit juice and ketoconazole upon clozapine administration in vivo

The drug-food and drug-drug interaction between grapefruit juice (GFJ) and ketoconazole (KETO) was evaluated in schizophrenic patients given a single dose of clozapine (CLZ). CLZ is metabolized primarily by CYP isozymes 3A4 and 1A2 to two principal metabolites, desmethylclozapine (DCLZ) and clozapine N-oxide (CNO). GFJ and KETO are well known potent CYP 3A4 inhibitors in the gastrointestinal tract and hepatic isozymes, respectively. Twenty-one schizophrenic patients participated in the co-administration of CLZ 50 mg and GFJ. After a one-week washout, five patients were given double the GFJ (HGFJ) dose for 7 consecutive days. In another group of five patients, ketoconazole (KETO) 400 mg was given for 7 consecutive days. At the end of the 7-day period for both groups, CLZ was coadministered with the HGFJ and KETO groups. CLZ, DCLZ and CNO were assayed by HPLC. GFJ, HGJF and ketoconazole failed to significantly change CLZ disposition. Metabolites DCLZ and CNO concentrations remained unchanged during the study. The only exception was decreased Cmax in DCLZ and CNO concentrations. These results indicate that CYP 3A4 inhibition may not be clinically significant compared to CYP 1A2, as previous studies show a dramatic increase in CLZ plasma concentrations with fluvoxamine (CYP 1A2 inhibitor). The reasons for the lack of drug-food and drug-drug interactions with CLZ and CYP 3A4 inhibitors can be explained by the higher Ki values for gastrointestinal and hepatic CYP 3A4 isozymes.

Alteration of mitogenic responses of mononuclear cells by anti-ds DNA antibodies resembling immune disorders in patients with systemic lupus erythematosus

Anti-double-stranded DNA antibodies (anti-DNA) purified from pooled active SLE sera by lambda phage DNA-affinity chromatography was found to affect phytohemagglutinin (PHA) and pokeweek mitogen (PWM)-induced responses of normal mononuclear cells. Anti-DNA at a concentration of 0.25 mg/ml (equivalent to 21 units/ml of DNA binding activity) significantly suppressed the PHA-induced [3H]thymidine incorporation of mononuclear cells in 3 days of culture but had no effect on 5-day and 7-day cultures. In contrast, a biphasic effect of anti-DNA on PWM response was found such that early phase (3-day culture) was inhibited whereas late phase (from 5 days to 9 days of culture) was enhanced by the antibodies. Anti-DNA also increased the immunoglobulin synthesis by PWM-stimulated B cells. The inhibition of PHA response in 3-day culture by anti-DNA is not due to changes in T cell subpopulations. Because interleukin 1 (10 units/ml) could restore the PHA response, it appears that anti-DNA suppressed the IL-1 production by monocyte/macrophage. The biphasic effect of anti-DNA on PWM response is the result of monocyte impairment and B cell stimulation by the antibodies. In the early phase (on day 3) the inhibition would seem to be due to impairment of accessory cell function by anti-DNA, though in late phase (after day 5) the anti-DNA may stimulate B lymphocytes to incorporate more thymidine in the presence of PWM. These biological effects of anti-DNA in vitro resemble the in vivo immunologic disorders in patients with SLE, in that impaired cell-mediated immunity and B cell hyperactivity are frequently observed.