IDEC-C2B8 anti-CD20 (rituximab) immunotherapy in patients with low-grade non-Hodgkin's lymphoma and lymphoproliferative disorders: evaluation of response on 48 patients

This study focused on the efficacy of IDEC-C2B8 (chimeric anti-CD20) immunotherapy relative to specific subtypes of low-grade lymphoproliferative disorders/non-Hodgkin's lymphomas (LPD/NHL). Forty-eight patients with resistant or relapsed disease completed the IDEC-C2B8 infusion schedule of 375 mg/m2/wk x 4 wk. The LPD/NHL subtypes included: (a) follicular centre cell lymphoma (FCC) in 22 patients; (b) mantle cell lymphoma (MCL) in 10; (c) 1 diffuse large cell lymphoma (DLCL); and (d) the category of small lymphocytic lymphoma/chronic lymphocytic leukaemia (SLL/CLL) and related disorders in 15 patients. No patient obtained a complete remission. Ten patients (21%) achieved partial remission: 6 FCC, 2 MCL, 1 DLCL and 1 patient from the SLL/CLL group. Twenty-eight patients had stable disease and 10 progressed during immunotherapy. In patients with CLL and MCL in leukaemic phase, there was no correlation between the marked decrease in circulating neoplastic cells following antibody infusions and amelioration of the tumour burden. The results suggest that the subtype of LPD/NHL and the intensity of CD20 on the tumour cells influence the effectiveness of IDEC-C2B8. The antibody was most efficacious against FCC lymphoma. The efficacy (at the dose schedule of 375 mg/m2/wk x 4) against MCL and SLL/CLL appeared to be limited, however.

A review of the present status of lymphatic filariasis in Vietnam

Establishing the current status of an infectious disease forms the starting point of any attempt at parasite control. Although data on the prevalence and distribution of lymphatic filariasis exist for Vietnam from the early 1900s, the present situation regarding the disease is less well-known. Here, we review the results of recent surveys conducted by the Institute of Malariology, Parasitology and Entomology, Hanoi, to update the existing information on filariasis epidemiology and distribution for this country. The present results are from surveys carried out on some 135,000 individuals in 24 provinces of Vietnam. The highest prevalences of microfilaraemia (primarily Brugia malayi ) are observed in lowland areas of the Red River Delta and in Quang-binh Province where the survey results show microfilaraemia (mf) prevalences in the range of 0.9-5.5%. The most common type of chronic clinical manifestation is shown to be leg elephantiasis. A significant finding is that an overall decrease in mf prevalence was observed to occur in five communities which were surveyed twice over an 11-21-year period, even though no interventions were carried out between the two surveys. The changes are probably caused by environmental changes, such as increased standards of housing and drainage. Studies on the effect of selective chemotherapy and mass chemotherapy using diethylcarbamazine showed reductions in community mf prevalences of 69 and 72-88%, respectively. Furthermore, cats do not appear to represent significant reservoirs of infection. These findings of geographical restriction of infection, effective and well-tolerated drug therapy, low significance of animal reservoirs, together with the existence of an effective national health network, suggest a good prognosis for the control of filariasis in this country.

Evaluation of the injured wrist on the field and in the office

The wrist is a common site of injury in sports, both acute and chronic. Evaluation of wrist injuries requires knowledge of anatomy kinematics, attention to the mechanism of injury, the intensity of training, and a focus on the physical examination for specific injuries.

[Access to health care for destitute persons at Public Assistance Hospitals in Paris]

All legal French residents are entitled to health care. The 1992 regulatory measures, which create a contractual agreement between the government and public medical institutions, aim at facilitating access to health care by resolving the financial obstacles to accessing health care. The Assistance Publique-Hôpitaux de Paris (AP-HP) has set up a medical reception center in several hospitals since 1993. This system is integrated in the general structure of each hospital: in some cases, there is a single and centralized unit; in other cases, all departments of the hospital, including the emergency room, are involved in caring for destitute patients. Whatever the type of the structure may be, social workers are a key element to helping the patients recover their social rights. Thirty to seventy-percent of patients visiting these centers regain access to social and health care coverage. The epidemiological survey of the active file of patients revealed that 70% are male, more than 50% are non-French nationals, half of which do not have legal immigration status in France. Homeless people represent 40 to 80% of the population. The average age is around 35. The number of medical visits varies greatly from one hospital to another and range from 20 to 60 per month. The reasons for visiting the center and the identified medical disorders are strongly related to the patients' life conditions and vary significantly with the risk factors related to the social and economic situation. The frequency of some diseases (psychiatric disorders, tuberculosis, infections by the HIV and HCV) is higher in this population than in general population. Delayed visits to the medical center represents a severity factor. The hospitals' mission statement is not only to ensure that patients facing a precarious social and professional situation have equal access to health care, but also to help such patients recover their social rights, facilitate their integration in the society and fight against social exclusion.

A comprehensive knowledge-based system for laboratory hematology

The Coulter FACULTY knowledge-based systems, Professor Petrushka for peripheral blood interpretation, Professor Fidelio for flow cytometry immunophenotyping and Professor Belmonte for bone marrow reporting, have been installed in several hospitals in Spain, Portugal and the United Kingdom. In Spain and Portugal, the systems are part of the IZASA-Coulter CITOTECA workstation, which includes a video camera for capturing microscopic images and a networkable laboratory information system supporting color reports. At the Royal Hospitals Trust (St. Bartholomew's Hospital and The Royal London Hospital, London, UK), networked workstations are available and the system is used daily to generate bone marrow reports in the hematology laboratories. There have been considerable benefits from adopting Coulter FACULTY for bone marrow reporting, including faster turnaround time, improved quality of the reports and cost savings.

Fast separation of underivatized carbohydrates by coelectroosmotic capillary electrophoresis

A method for the rapid quantitative analysis of underivatized acidic sugars, monosaccharides and disaccharides using coelectroosmotic capillary electrophoresis was developed. Indirect UV detection at 254 nm using sorbate as background electrolyte was employed for monitoring the analytes. A highly alkaline pH value of the electrolyte system was chosen in order to achieve an electrophoretic mobility of the saccharides towards the anode. A dynamic reversal of the electroosmotic flow and, by this means, a codirectional movement of the negatively charged analytes and the electroosmotic flow is accomplished by employing a polycationic surfactant (hexadimethrine bromide), which is added to the background electrolyte. To further improve the resolution of specific carbohydrates, acetone is used as organic modifier. A practical application of the developed method for the fast determination of fructose, glucose, and sucrose in various soft drinks is provided.

Haematological validation of a computer-based bone marrow reporting system

AIMS

To prove the safety and effectiveness of "Professor Belmonte", a knowledge-based system for bone marrow reporting, a formal evaluation of the reports generated by the system was performed.

METHODS

Three haematologists (a consultant, a senior registrar, and a junior registrar), none of whom were involved in the development of the software, compared the unedited reports generated by Professor Belmonte with the original bone marrow reports in 785 unselected cases. Each haematologist independently graded the quality of Belmonte's reports using one of four categories: (a) better than the original report (more informative, containing useful information missing in the original report); (b) equivalent to the original report; (c) satisfactory, but missing information that should have been included; and (d) unsatisfactory.

RESULTS

The consultant graded 64 reports as more informative than the original, 687 as equivalent to the original, 32 as satisfactory, and two as unsatisfactory. The senior registrar considered 29 reports to be better than the original, 739 to be equivalent to the original, 15 to be satisfactory, and two to be unsatisfactory. The junior registrar found that 88 reports were better than the original, 681 were equivalent to the original, 14 were satisfactory, and two were unsatisfactory. Each judge found two different reports to be unsatisfactory according to their criteria. All 785 reports generated by the computer system received at least two scores of satisfactory or better.

CONCLUSIONS

In this representative study, Professor Belmonte generated bone marrow reports that proved to be as accurate as the original reports in a large university hospital. The haematology knowledge contained within the system, the reasoning process, and the function of the software are safe and effective for assisting haematologists in generating high quality bone marrow reports.

Simulation of the enzyme reaction mechanism of malate dehydrogenase

A hybrid numerical method, which employs molecular mechanics to describe the bulk of the solvent-protein matrix and a semiempirical quantum-mechanical treatment for atoms near the reactive site, was utilized to simulate the minimum energy surface and reaction pathway for the interconversion of malate and oxaloacetate catalyzed by the enzyme malate dehydrogenase (MDH). A reaction mechanism for proton and hydride transfers associated with MDH and cofactor nicotinamide adenine dinucleotide (NAD) is deduced from the topology of the calculated energy surface. The proposed mechanism consists of (1) a sequential reaction with proton transfer preceding hydride transfer (malate to oxaloacetate direction), (2) the existence of two transition states with energy barriers of approximately 7 and 15 kcal/mol for the proton and hydride transfers, respectively, and (3) reactant (malate) and product (oxaloacetate) states that are nearly isoenergetic. Simulation analysis of the calculated energy profile shows that solvent effects due to the protein matrix dramatically alter the intrinsic reactivity of the functional groups involved in the MDH reaction, resulting in energetics similar to that found in aqueous solution. An energy decomposition analysis indicates that specific MDH residues (Arg-81, Arg-87, Asn-119, Asp-150, and Arg-153) in the vicinity of the substrate make significant energetic contributions to the stabilization of proton transfer and destabilization of hydride transfer. This suggests that these amino acids play an important role in the catalytic properties of MDH.

Effects of earplugs on catecholamine and cortisol excretion in noise-exposed textile workers

To investigate physiological and psychological effects of industrial noise, a survey was performed on 50 female workers exposed to machinery noise [93-100 dB(A)] (noise group) and 25 female workers in less-noisy environments [71-75 dB(A)] (control group) in a textile factory in Vietnam. Urine was collected for analysis of catecholamines and cortisol. The subjects were also asked to fill out a questionnaire. Each subject was examined over 2 working days. The workers in the noise group were asked to put earplugs in their ears during the working hours of the 2nd day. On the 1st day without earplugs, urinary excretion of catecholamines in the noise group were greater than those in the control group. Cortisol in urine showed a similar tendency. Differences in catecholamine excretion between the noise group and the control group decreased on the 2nd day when the earplugs were used for attenuation of noise level in the noise group. Frequency of subjective fatigue symptoms was lower on the 2nd day than that on the 1st day in noise group, while the control group showed almost no day-difference. The results indicate that the catecholamine response to noise in workers was reduced through the use of earplugs.

Multiparameter case studies using knowledge-based systems in hematology

Knowledge-based systems in diagnostic medicine are often used for teaching medical decision making. We have extended the educational value of our suite of hematology decision support systems (peripheral blood analysis, flow cytometry immunophenotyping and DNA analysis, and bone marrow morphology) by creating case studies in a hypertext format. The case studies use the knowledge-based system screens as a background. Digitized images of blood and bone marrow smears from the teaching cases can be accessed on-line. The case studies, which are designed primarily for technologists and physicians, emphasize the proper multiparameter approach to hematopathology diagnosis.

Chronic lymphocytic leukemia with an interfollicular architecture: avoiding diagnostic confusion with monocytoid B-cell lymphoma

Certain low grade B-cell lymphoproliferative disorders can be mistaken for each other morphologically, particularly when there is partial lymph node involvement. We encountered two cases of chronic lymphocytic leukemia, in which the interfollicular growth pattern and the pale appearance of the neoplastic proliferation in the lymph nodes led to a misclassification as monocytoid B-cell lymphoma. The correct diagnosis was established, however, when the lymph node morphology was carefully reexamined, with the knowledge of the clinical history, peripheral blood findings, and bone marrow data. The immunophenotype of the neoplastic cells in the peripheral blood (CD5, CD23, weak fluorescence intensity of surface immunoglobulin and CD22) and the lymph node immunohistochemistry (weak L26 staining, strong MT1 positivity) confirmed the diagnosis of chronic lymphocytic leukemia. These two cases demonstrate the necessity of a systematic approach to lymph node morphology and the utility of a multiparameter approach in the diagnosis of lymphoproliferative disorders.

Are normative expert systems appropriate for diagnostic pathology?

Conceptual models for diagnostic reasoning proposed in the medical literature are presented to stimulate discussion about the issue of the appropriateness of probabilistic knowledge-based systems for medical diagnosis. Evidence is presented to corroborate the authors' view that diagnosis is a problem-solving task, rather than a decision-making task. In the authors' opinion, probabilistic reasoning is better suited to situations dealing with choices for clinical intervention, rather than to those dealing with determining the correct diagnosis. A critique is given of a diagnostic Bayesian expert system for lymph node pathology. In empirical studies, diagnostic Bayesian systems have been shown to typically list the correct diagnosis as the program's first choice 60% to 70% of the time. One reason for this undistinguished level of diagnostic performance is that Bayesian systems are not designed to represent and use knowledge the same way that an expert does.

Balloon dissection facilitated laparoscopic extraperitoneal hernioplasty

BACKGROUND

With the goals of minimizing perioperative morbidity and obtaining direct inguinal access without transgressing the peritoneal cavity, we developed a balloon dissection device to facilitate laparoscopic extraperitoneal hernioplasty.

PATIENTS AND METHODS

We have performed balloon facilitated dissection on 113 patients (105 males) on an outpatient basis. Some patients were repaired under regional anesthesia. A total of 150 hernias have been repaired: 72 indirect, 70 direct, 3 scrotal, 2 sliding, 2 spigelian, and 1 femoral.

RESULTS

Mean operating time was 60 minutes. All patients were ambulatory on discharge. Half reported minimal or no immediate postoperative pain. Over 80% had only minimal irritation or discomfort on the third postoperative day. Nearly 60% returned to work within 2 weeks. None required hospital readmission for an immediate complication of hernioplasty. With a mean follow-up of 6.3 months, only three recurrences are reported. Except for one persistent neuropathy which resolved after staple removal, there were no significant complications.

CONCLUSIONS

We conclude that balloon dissection facilitates laparoscopic extraperitoneal hernioplasty and obviates the need for general anesthesia. Our approach minimizes perioperative pain. It can be done on an outpatient basis and permits prompt return to full activity including physical work.

Potential diagnostic pitfalls caused by blood film artifacts in prolymphocytic leukaemia. Observations in two cases

The diagnosis of lymphoproliferative disorders is based on a combined evaluation of the clinical, immunological and morphological findings. Cytological details may vary with the quality of the smear. We report two cases of prolymphocytic leukaemia in which cytoplasmic hairs or protrusions were observed when the films were not dried quickly. In one case the artifacts led to an initial erroneous interpretation of hairy cell leukaemia 'variant'. The cytoplasmic outline was smooth in both cases when the smears were immediately fan-dried. The findings underscore the necessity of high standards of excellence, even for the simple technique of blood film preparation, in order to avoid undesirable artifacts which may result in diagnostic misinterpretation.

Multiparameter interpretative reporting in diagnostic laboratory hematology

Accurate diagnosis and classification of hematologic malignancies (acute leukemias and chronic lymphoproliferative disorders) requires a multiparameter approach including peripheral blood analysis, bone marrow examination, and immunophenotyping. We have designed knowledge-based computer systems for interpretation of the hemogram and peripheral blood smears, analysis of flow cytometric immunophenotyping panels, and morphologic assessment of bone marrow specimens. The 3 modules share a relational database which includes pertinent clinical history in addition to the laboratory results. The bone marrow module automatically writes a complete interpretative report with a final diagnosis by searching all of the databases for appropriate clinical, peripheral blood, and immunophenotyping information. The ability of the 3 modules to interact, and the quality of the interpretative reports were tested on 100 consecutive patients with leukemia. The final diagnosis made by the bone marrow system agreed with the hospital diagnosis in 94 cases and the authors' interpretation in 99 of 100 cases.

A knowledge-based system for the interpretation of flow cytometry data in leukemias and lymphomas

Flow cytometry immunophenotyping and analysis of DNA ploidy and proliferative activity have become extremely helpful techniques for diagnosing and subclassifying hematopoietic cell populations in a modern, full-service hematopathology laboratory. The number of physicians with special training in the interpretation of these studies is limited. A knowledge-based computer system has been designed to aid in the interpretation of immunophenotyping and DNA flow cytometry results in hematopoietic disease. The system, known as "Professor Fidelio," is a heuristic classification system that reasons on the basis of defined diagnostic patterns. In this study, Fidelio was tested as a stand-alone system on 366 specimens from two large tertiary medical centers. Fidelio's interpretation was considered to be appropriate in all cases. In 300 of 366 (82%) specimens, the system's interpretation agreed with the diagnosis of record. Many of the disagreements could be traced to errors in the recording of the original diagnosis and minor differences in diagnostic criteria between Fidelio's knowledge base and the criteria in use at the medical centers. When used in a stand-alone mode, Fidelio's interpretation was less specific than the diagnosis of record in certain lymphoproliferative disorders that require morphologic information for subclassification. Professor Fidelio is one module in a workstation for the diagnostic hematology laboratory. This workstation is designed for interpretive reporting, education, and database functions for clinical research. Clinical and morphologic information are shared between Fidelio and the other modules for peripheral blood analysis, bone marrow morphology, and lymph node interpretation by means of a relational database. The system will be useful in hospitals that lack individuals specially trained in flow cytometry.(ABSTRACT TRUNCATED AT 250 WORDS)

An unusual pattern of lymph node involvement in mycosis fungoides simulating neoplastic follicles

We describe an unusual pattern of lymph node involvement in a case of mycosis fungoides. The neoplastic proliferation formed pale nodules composed of small, irregular lymphoid cells, features that, on routine paraffin sections, suggested neoplastic follicles and a B-cell phenotype. The correct diagnosis was established by immunohistochemical studies that demonstrated a T-cell phenotype. Polymerase chain reaction for rearrangement of the T-cell receptor gamma gene confirmed that the proliferation was monoclonal. This case demonstrates that both architectural pattern and cytologic features may be unreliable in predicting immunologic phenotype. Immunologic marker studies and careful attention to the clinical history are vital to classify lymphoproliferative disorders correctly.

Castleman's disease. Differences in follicular dendritic network in the hyaline vascular and plasma cell variants

Twenty-seven cases of the hyaline vascular variant and 10 cases of the plasma cell variant of Castleman's disease were studied with the paraffin resistant monoclonal antibodies Ki-FDC1p and/or Ki-M4p against follicular dendritic cells. Studies with the monoclonal antibody Ki-M9, for the detection of sinus lining cells, were also performed on the available frozen tissue in four cases of the hyaline vascular variant. In nine of the 10 plasma cell variant cases, the predominant type of follicular dendritic cell network was similar to that seen in normal or reactive germinal centres. In contrast, the hyaline vascular variant demonstrated either an expanded, disrupted, follicular dendritic cell network (10 cases) or multiple tight collections of follicular dendritic cells (16 cases). Sinus lining cells were not detected in the four cases studied. The difference in the predominant type of dendritic meshwork is an additional distinguishing feature to separate the plasma cell and hyaline vascular variants of Castleman's disease. The patterns of dendritic network seen in the hyaline vascular type, together with the absence of sinus lining cells, appear to favour the hamartoma theory proposed for this variant.

An expert system for the interpretation of flow cytometric immunophenotyping data

The development of high-grade non-Hodgkin's lymphomas in HIV-positive patients and patients with acquired immune deficiency syndrome (AIDS) is a well known phenomenon. The proper classification of these neoplasms often requires a multiparameter approach, including the interpretation of a large panel of immunologic markers analyzed by flow cytometry. The availability of individuals with the required expertise to properly interpret these marker studies is limited. For this reason, we have designed an expert system to automate the analysis of immunophenotyping panels in both HIV-related and non-HIV-related hematopoietic neoplasms. The expert system, which we call "Professor Fidelio", runs on IBM-compatible computers under Windows 3.0. The system is designed to accept any number of markers studied from a repertoire of 35 markers. Professor Fidelio functions on the basis of heuristic classification of defined diagnostic patterns. Nine specific patterns (Stem Cell, Myeloid and/or Monocytic, Erythroid, Megakaryocytic, Immature B-cell, Immature T-cell, Mature B-cell, Mature T-cell, and Plasma cell) and one "non-specific" pattern have been agreed upon. Fidelio's knowledge base contains the definitions of each of these patterns and the heuristics for excluding patterns when an incomplete panel of markers is performed. The inference engine interprets the findings (including the age of the patient) and reports the patterns which are matched, the differential diagnosis, the suggested diagnosis from the list of differentials if the marker studies are specific, and recommendations for additional tests which may be valuable in establishing the diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunological priming attenuates the in vivo pathophysiological response to lipopolysaccharide. Comparison of cytokine production, tissue injury, and lethality in complete Freund's adjuvant-primed mice and in unprimed mice

Previous reports have indicated that immunological priming of animals will result in increased cytokine production and enhanced susceptibility to the toxicity of cytokines. We primed mice with complete Freund's adjuvant and challenged 2 weeks later with 1 mg/mouse of lipopolysaccharide. Primed mice produced less tumor necrosis factor than naive mice (35 +/- 8 vs 108 +/- 20 ng/ml) and also less interleukin-6 (182 +/- 37 vs 6.39 +/- 155 ng/ml). Leukopenia developed only in the naive mice. Although neutropenia and lymphocytosis developed in both groups, the alterations manifested themselves more quickly in primed mice. Primed mice had substantially greater pulmonary neutrophil sequestration determined both enzymatically and histologically but no lung damage. However, primed mice had significantly less small bowel damage than naive mice. Mortality was substantially reduced in primed mice compared with unprimed mice. These results demonstrate that immunological priming in vivo decreases cytokine production in response to lipopolysaccharide challenge, decreases organ injury, and reduces mortality.

Costimulation of cutaneous T-cell lymphoma cells by interleukin-7 and interleukin-2: potential autocrine or paracrine effectors in the Sézary syndrome

PURPOSE

To examine interleukin-7 (IL7)- and interleukin-2 (IL2)-induced proliferation of Sézary lymphoma cells and to consider if an autocrine or paracrine growth-stimulatory circuit involving IL7 exists in the Sézary syndrome (SS).

MATERIALS AND METHODS

Fresh Sézary lymphoma cells were maintained in short-term culture in the presence of cytokines, and growth was measured by incorporation of (3H)-thymidine (TdR). Expression of IL7 and IL7 and IL2 receptors (IL7-R and IL2-R, respectively) was assessed by polymerase chain amplification of first-strand complementary DNA (RT-PCR), by affinity cross-linking of radioactive iodine-125-IL7, and by dual-color fluorescence-activated cell analysis. IL-7 production was measured by immunoassay.

RESULTS

Sézary lymphoma cells from seven patients showed synergistic (five of seven) or additive (two of seven) proliferation when cultured in the presence of IL2 and IL7, as compared with culture with either cytokine alone. Two patients with evidence of synergistic stimulation of [3H]-TdR incorporation showed IL7-R gene expression by RT-PCR and IL7 affinity cross-linking. Incubation of all seven patients' cells with IL7 induced coexpression to varying degrees of IL7-R and IL2-R. Sézary lymphoma cells from at least three of five patients studied expressed IL7 mRNA, and skin from three of five patients studied, as well as normal skin, expressed IL7 mRNA by RT-PCR.

CONCLUSION

Sézary lymphoma cells respond by proliferation to IL7 plus IL2, and in some instances produce IL7. Therapeutic maneuvers should be pursued to take advantage of this potential autocrine or paracrine growth-stimulatory mechanism.

A clinical database as a component of a diagnostic hematology workstation

A clinical database was designed as part of a comprehensive workstation for diagnostic laboratory hematology. The database stores coded findings pertinent to hematologic disorders including inherited abnormalities, previous surgery, malignancies, current therapy, and laboratory test results. The workstation includes knowledge-based systems for peripheral blood analysis, flow cytometry studies, and bone marrow morphology. The peripheral blood system renders an interpretive report based on data from a complete blood count with manual review of a blood smear by a technologist. The flow cytometry module interprets the immunophenotyping and DNA content results, and correlates them with the clinical findings and the peripheral blood data. The bone marrow system bases its report on all of the available information including the morphologic review of the bone marrow specimen by a physician, the peripheral blood data, immunophenotype, and clinical/laboratory findings. Before generating an interpretive report, each of the knowledge-based systems automatically searches the clinical database for specific information pertinent to the findings in the case. Since the workstation must function in situations where access to distributed databases is not feasible or not yet practical, a data entry module with a graphical user interface has been created.