A new method for the simultaneous analysis of growth and death of immunophenotypically defined cells in culture

BACKGROUND

Internal standards have been used in flow cytometry methods to enumerate lymphoid subsets and hemopoietic progenitor cells ex vivo. However, the currently available methods cannot be readily applied to the analysis of cultured cells because of the frequent occurrence of cell death during in vitro assays.

METHODS

This paper reports a new method for the enumeration of both viable and nonviable cells in culture. Cells were counted with the aid of an internal reference standard of microbeads, and live versus dead cell discrimination was performed using 7-amino-actinomycin D which allows the double staining of surface antigens.

RESULTS

The method is more precise, accurate and sensitive than either conventional light microscopy-based or automated cell counting. Additionally, it may be used to accurately measure the number of apoptotic cells in a culture.

RESULTS

Through the enumeration of surviving cells it is demonstrated that, when applied to the study of mitogen-activated T lymphocytes, current flow cytometry techniques (which do not use internal standards) for the study of the viability and apoptosis overestimate the fraction of viable cells and underestimate both the fraction of dead and apoptotic cells.

CONCLUSIONS

The new method overcomes these limitations and is of use in the in vitro study of cell growth and apoptosis.

Chicken anemia virus and fowl adenoviruses: association to induce the inclusion body hepatitis/ hydropericardium syndrome

The effects of a simultaneous and/or a subsequent coinfection with chicken anemia virus (CAV) isolate 10343 and fowl adenovirus (FAV) isolate 341 in specific-pathogen-free light chickens were evaluated. The simultaneous coinfection was conducted by the intramuscular route, whereas the subsequent coinfection trial considered FAVs administered orally. In trial 1, 20-day-old chickens simultaneously coinfected with CAV (10343) and FAV (341) intramuscularly (i.m.) showed 55% mortality and characteristic signs and lesions of inclusion body hepatitis/hydropericardium (IBH/HPS). In contrast, birds singly infected with FAV i.m. showed 10% mortality due to IBH/HPS. Trial 2 showed that birds receiving FAV 341 orally at day 7 post-CAV intramuscular infection (group A) developed a mild form of IBH/HPS with presence of inclusion bodies (INIBs) in 60% of the group and virus-neutralizing antibodies against FAV 341. Group B (FAV orally 14 days after CAV) showed significant decreased weight gain, nonspecific microscopic lesions in the liver, spleen, bursa, and thymus, and an antibody response against FAV 341. However, no INIBs could be detected in the hepatocytes of these chickens. Group C (FAV orally 35 days after CAV) showed nonspecific histopathologic changes in the liver and no antibody response to FAV. The oral single infection with FAV isolate 341 induced neither mortality nor macroscopic lesions of IBH/HPS in the birds. The present results corroborate previous reports on pathogenicity of Chilean FAV isolates, which suggest that synergism with other viruses or prior immunosuppression is necessary to produce IBH/HPS in chickens. These results also suggest that the susceptibility of chickens to FAV oral infection resulting in IBH/HPS varies throughout the course of CAV infection.

Contamination of peritoneal dialysis fluid by filamentous fungi

Peritonitis is a frequent complication in peritoneal dialysis. It may be caused by contamination of the dialysis tubing or by extension of the catheter exit site. Gram-positive bacteria are the most common organism, accounting for 60% of all documented cases of continuous ambulatorial peritonitis dialysis. Fungi are isolated from to 1-15% of cases. Forty-nine out of 490 bottles containing fluid for peritoneal dialysis were randomly selected for microbiological analysis in São Paulo, Brazil. In this report the contamination of peritoneal dialysis fluid by Chaetomium globosum and Chrysonilia sitophila is reported.

Oculocardiac reflex in sedated patients having laser in situ keratomileusis

PURPOSE

To eliminate stress as a variable in assessing the frequency of the oculocardiac reflex during laser in situ keratomileusis (LASIK).

SETTING

Merida Ophthalmological Hospital and Oftalmedica, Mexico City, Mexico.

METHODS

A pulse oximeter registered the heart rate of 30 sedated patients having LASIK. Sedation was accomplished with a combination of midazolam and fentanyl. The heart rate was noted before and during suction. The results in 1 eye of each patient were recorded. Oculocardiac reflex was defined as a decrease of 10% or more of the basal heart rate.

RESULTS

Fourteen patients (46.7%) had a 10% or more decrease in heart rate when suction was applied. Ten of the 14 had a decrease in heart rate between 10% and 19%, 3 between 20% and 29%, and 1 of more than 30%. Two patients (6.6%) had an increase in the basal heart rate of more than 10%.

CONCLUSIONS

The findings suggest that the oculocardiac reflex occurs more frequently in sedated patients than in nonsedated patients.

Epstein-Barr virus-associated gastric carcinoma in Mexico: analysis of 135 consecutive gastrectomies in two hospitals

Epstein-Barr virus (EBV) has been implicated in the genesis of gastric carcinoma. The presence of clonal episomal viral forms in the nuclei of neoplastic gastric epithelial cells suggests that viral infection occurs before the development of gastric carcinoma. Mexico is a country at high risk for gastric cancer-it is the second cause of death among patients who die of cancer in that country. A series of 135 consecutive non-selected gastrectomies from two hospitals in Mexico City were analyzed to search for EBV in gastric carcinomas. EBV-encoded small non-polyadenylated RNA (EBER) in situ hybridization was performed on 5-microm paraffin-embedded tissue sections. Age, gender, anatomical site, histological type, and invasiveness of gastric carcinomas were obtained from the records in the corresponding Departments of Pathology. Eleven (8.15%) of the 135 cases were EBER-1-positive gastric carcinomas. Six occurred in males and five in females. In three women, the neoplasia was localized in the antrum. Five of the 11 cases were lymphoepithelioma-like carcinomas and, in two of them, an unusual foreign body-type inflammation was observed. Environmental factors could influence the distinctive pathologic features of EBV-associated gastric carcinoma in the Mexican population.

Defective proliferative response of T lymphocytes from patients with inactive systemic lupus erythematosus

OBJECTIVE

To further define the pattern of alterations in the activation and apoptosis of T lymphocytes in patients with inactive systemic lupus erythematosus (SLE) through analysis of a large series of individuals.

METHODS

We isolated CD2+ peripheral blood lymphocytes (PBL) from 41 patients with inactive SLE and analyzed their proliferative and apoptotic responses to polyclonal activation.

RESULTS

In 19 of 41 (47%) patients, a low proliferative response to polyclonal mitogens was found. This defective response was inversely associated with an increased apoptotic response and increased expression of CD95 and CD45RO antigens.

CONCLUSION

We found that 2 groups of patients with inactive disease can be defined according to the functional behavior of their T lymphocytes, as defined by the proliferative and apoptotic responses to mitogenic signals.

High prevalence of a 30-base pair deletion in the Epstein-Barr virus (EBV) latent membrane protein 1 gene and of strain type B EBV in Mexican classical Hodgkin's disease and reactive lymphoid tissue

Depending on geographic location and patient age Hodgkin's disease (HD) is associated with Epstein-Barr virus (EBV), mostly type A EBV, in 20% to 100%. The highest prevalence occurs in children of developing countries. Molecular analysis of the oncogene coding for the latent membrane protein 1 (LMP-1) revealed a 30-base pair (bp) deletion in up to 46% of EBV-positive HD. We investigated the presence of EBV in a series of Mexican classical HD (n = 57) and reactive lymphoid tissues (n = 20) from a private and a public hospital with special emphasis on the prevalence of the 30-bp deletion and the type of EBV. EBV infection was analyzed at the cellular level by Epstein-Barr encoded early RNA transcripts (EBER) in situ hybridization (ISH) and by LMP-1 protein immunohistochemistry (IHC). Molecular analysis of the LMP-1 gene configuration was performed by polymerase chain reaction (PCR) with primers spanning the site of the deletion and subsequent Southern and/or dot blot hybridization using wild-type and deletion-specific probes. The prevalence of type A and type B EBV was investigated by PCR-analysis for divergence in the coding region of Epstein-Barr nuclear antigen (EBNA)-2. EBV was detected in Hodgkin- and Reed-Sternberg cells (H-RS) by LMP-1 IHC and/or EBER ISH in 35/57 (61%) Mexican HD including 18/32 (56%) with nodular sclerosis, 15/20 (75%) with mixed cellularity and 2/4 (50%) with lymphocyte depletion. In addition, LMP-1 gene sequences were detected by PCR in 9 cases of HD without LMP/EBER expression by H-RS cells and in 17/20 (85%) reactive lymph nodes, supposedly originating from rare latently infected B cells. Surprisingly, the 30-bp LMP-1 deletion was found in 28/35 (80%) EBV-positive HD. This deletion, however, was also found in all 9 (100%) HD with H-RS cells negative for EBV and in 10/17 (59%) reactive lymph nodes. Thus, the overall LMP-1 del prevalence in reactive tissue is 73% (19/26). Typing of EBV was successful in 26 cases of EBV-positive HD, 10 of these were infected by type B EBV (38%). Of the reactive lymphoid tissue, 9 (47%) were infected by type A, and 10 (53%) by type B; All 20 cases (100%) associated with type B, whether neoplastic or reactive, displayed the LMP-1 del variant compared with 18/25 (72%) infected by type A EBV. To our knowledge, this is the highest incidence for both the LMP-1 deletion variant and the infection by type B EBV in HD reported so far worldwide. Our data suggest that EBV infection contributes to the pathogenesis of the majority of Hodgkin's disease cases in Mexico. The specific tumorigenic role of the LMP-1 deletion variant, however, is doubtful with regard to its high frequency in nonneoplastic lesions. Moreover, type B infection frequently occurs in Mexican HD and reactive lymphoid tissue and is consistently associated with the deletion variant pointing to a pathogenetic role of this combined genotype.

An epidemic outbreak of Malassezia folliculitis in three adult patients in an intensive care unit: a previously unrecognized nosocomial infection

BACKGROUND

Malassezia is a lipophilic fungus commonly found in normal human skin. Infection of the hair follicle by Malassezia furfur occurs in patients with predisposing factors such as diabetes or immunosuppression, or who are undergoing antibiotic treatment. Malassezia furfur folliculitis is an infrequent nosocomial infection which may be associated with fomite transmission.

METHODS

We reviewed the clinical files of three adult patients from an intensive care unit (ICU) who simultaneously developed folliculitis through Malassezia infection. We specifically analysed predisposing factors, possible transmission modes, characteristics of skin lesions, results of biopsies and cultures, treatment, and patient outcome.

RESULTS

The three male patients were in neighboring beds and they all had factors that predisposed them to underlying immunosupression. Simultaneously, and within hours of each other, they developed erythematous follicular papules and pustules on the face and chest. The skin biopsies revealed an acute folliculitis with abundant round to oval yeasts of up to 5 microm in diameter. Stains for fungi (Schiff's peryodic acid, Grocott and silver methenamine) revealed numerous unipolar budding yeasts without hyphae, consistent with M. furfur. Conventional cultures were negative. The diagnosis of folliculitis by M. furfur was established and antifinigal treatment initiated, with adequate outcome of the dermatosis. After this outbreak, the aseptic and hygienic measures of the health care personnel of the ICU were reviewed and corrected.

CONCLUSIONS

The simultaneous emergence of this superficial infection by M. furfur suggests fomite participation. This dermatomycosis is an infrequent nosocomial infection in adults, which to our knowledge has not been previously reported.

Prevention by a silymarin/phospholipid compound of ethanol-induced social learning deficits in rats

We explored the possibility that silymarin (SY), a fraction from Silybum marianum, might protect against the effects of in utero exposure to ethanol upon subsequent social memory function. Three groups of 8 pregnant female Sprague-Dawley rats each were provided with a liquid diet containing 35% ethanol derived calories (EDC). One experimental group received a daily subcutaneous injection of 400 mg/kg SY, the second, a 400 mg/kg oral dose of SY, a third group was maintained on the 35% EDC diet. A fourth group served as the pair-fed control group. The liquid diet regimen was maintained throughout pregnancy. Rats pups were fostered by dams in a fifth group that had been maintained on rat chow. At 90 days the pups were tested for social memory. Social recognition scores recorded for the ethanol pups were significantly poorer than those observed in both SY/ethanol groups and the chow group.

Granulocyte colony-stimulating factor (G-CSF) transiently suppresses mitogen-stimulated T-cell proliferative response

Granulocyte colony-stimulation factor (G-CSF) is a cytokine that selectively promotes growth and maturation of neutrophils and may modulate the cytokine response to inflammatory stimuli. The purpose of this study was to examine the effect of G-CSF on ex vivo peripheral blood mononuclear cell (PBMC) functions. Ten patients with breast cancer were included in a clinical trial in which r-metHuG-CSF was administered daily for 5 days to mobilize peripheral blood stem cells. Ten healthy women were also included as controls. Our data show that G-CSF treatment induces an increase in peripheral blood leucocyte, neutrophil, lymphocyte and monocyte counts. We have found a modulation in the percentages of CD19+, CD45+ CD14+, CD4+ CD45RA+ and CD4+ CD45RO+ cells in PBMC fractions during G-CSF treatment. We have also found a significant reduction in the proliferative response of PBMC to mitogenic stimulation that reverted 14 days after the fifth and the last dose of G-CSF. Furthermore, it was not associated with significant changes in the pattern of cytokine production. The mechanism of this immunoregulatory effect is probably indirect since G-CSF receptor has not been found in T lymphocytes. This mechanism and its potential clinical applications remain to be elucidated.

Protective effects of the flavonoid mixture, silymarin, on fetal rat brain and liver

We investigated the possibility that the flavonoid mixture, silymarin (SY), administered as the compound Silymarin Phytosome (PHYTO), could protect the fetus from maternally ingested EtOH. Seventy-six female rats were randomly assigned to one of seven groups: pair-fed control; chow fed control; EtOH; and four groups receiving EtOH and PHYTO in varying dosages. All groups except the chow-fed control were maintained on a liquid diet. On day 1 of pregnancy the dams began the treatment protocol. On day 21 of pregnancy the rats were sacrificed and the fetuses removed. Gamma glutamyl transpeptidase (GGTP) activity was determined for liver and brain tissue from both the fetuses and the dams. GGTP activity in the EtOH/silymarin treatment groups did not differ significantly from that observed for the pair-fed control group. The observed GGTP activity levels for the EtOH-only group were significantly higher than those attained by the pair-fed control group. Although GGTP activity did not vary significantly with the quantity of PHYTO administered, as PHYTO dose was increased, GGTP activity decreased.

The association between CD2+ peripheral blood lymphocyte subsets and the relapse of bladder cancer in prophylactically BCG-treated patients

We investigated the potential existence of differences in the distribution of T-lymphocyte subsets and in the proliferative response of these CD2+ cells to polyclonal mitogens in patients with transitional cell bladder carcinoma (SBTCC) treated with prophylactic intracavitary instillations of bacillus Calmette-Guerin (BCG) according to their clinical response to this treatment. Before BCG treatment, different subset distribution (CD8+ and CD3+ CD56+), activation antigen expression (CD3+ HLA- DR+) and proliferative response to mitogenic signals were found in CD2+ cells from SBTCC patients prophylactically treated with BCG who remained free of disease or those who had recurrence of tumour. Otherwise, the prophylactic intracavitary BCG instillations in SBTCC patients are associated with a transitory variation of T-lymphocyte subset distribution (CD4 and CD8) and activation antigens expression (CD25).

Abnormal functional behavior of peripheral blood mononuclear cells from Hashimoto's disease patients. Immunomodulatory effects of cyclosporin A

In vitro studies of activation and proliferation induced by mitogens in the presence of Cyclosporin A (CsA) and or cytokines were carried out to determine the effects of CsA and cytokines on mitogen activated peripheral blood mononuclear cells (PBMC) from thirteen Hashimoto's disease patients (HP) and ten healthy controls. The proliferative response (PR) of PBMC from HP to mitogens at 7 days of culture was higher than in controls. Interleukin 2 (IL-2) addition significantly increased the PR in phytohemagglutinin-stimulated PBMC from HP, but not in controls. CsA inhibited in a dose dependent manner the PR, as well as the expression of activation antigens induced by mitogens in both groups of subjects, but PBMC from HP were sensitive to CsA at lower doses than those that were effective on PBMC from controls. Both IL-2 or IL-4 overcame the inhibitory effect of CsA on PBMC from HP and controls. Conversely, IL-10 or IFN-alpha addition increases the inhibitory effect of CsA on the PR of PBMC from both HP and controls. We conclude that PBMC from Hashimoto's disease patients shown an abnormal pattern of PR that is associated to increased PR to mitogens and higher sensitivity to immunomodulatory effects of IL-2 and CsA.

Eradication therapies for Helicobacter pylori

Eradication therapies for Helicobacter pylori evolved from monotherapy, through dual therapies and finally to bismuth-based triple therapies by the mid-1980s. The advent of proton pump inhibitors (PPI) and clarithromycin added a new impetus in the development of newer and often more effective regimens. Following large numbers of therapeutic trials, two broad groups of therapies stand out which consistently achieve over 90% eradication. Both are PPI-based. PPI/amoxycillin/clarithromycin twice daily therapy is the simplest but perhaps the most expensive. The 7-day quadruple (quad) therapy, consisting of a PPI and bismuth/tetracycline/metronidazole, is rapidly emerging as the "all rounder" therapy able not only to overcome metronidazole and clarithromycin resistance but to also have a consistently high eradication rate of well over 90%. Extensive clinical use of older and cut-down versions of combination therapies is resulting in a rising population of treated patients who continue to be infected with H. pylori, often resistant to further eradication attempts. Failure to recognise the need to use regimens which achieve high first-time eradication success will lead inexorably to an enlarging pool of patients with resistant strains and "difficult-to-eradicate" H. pylori.

[Cutaneous histoplasmosis in nine patients with AIDS]

In AIDS patients the diagnosis of systemic mycosis is a clinical challenge. When cutaneous affection occurs, the diagnosis is difficult because of the non-specific clinical findings. We describe nine patients with AIDS and cutaneous histoplasmosis as the initial clinical manifestation. These patients were diagnosed from 1987 to 1998. In all the diagnosis of histoplasmosis was done by skin biopsy and fungal isolation. The main skin lesions were papules combined with pustules or nodules in 6 of 9 patients, ulcers (1/9), erythematous plaques (1/9) and nodules (1/9). Head and trunk were the main anatomical locations of the lesions. All had fever, 7/9 had liver and spleen enlargement and 5/9 had weight loss. At the time of diagnosis all patients had a low CD4+ lymphocyte counts with a mean of 47 cells/microL. Amphotericin B was the initial treatment followed by itraconazole. Five patients died, one day after diagnosis and four after 5, 8, 11 and 12 months. Four are alive at 3, 3, 19 and 26 months of follow-up.

CONCLUSIONS

In AIDS patients the skin involvement by histoplasmosis should always be included among the differential diagnoses specially in patients with face and trunk papules and fever and hepatosplenomegaly. Skin and bone marrow cultures were the most reliable diagnostic methods, but skin biopsy was the fastest procedure.

Primary intestinal non-Hodgkin's lymphoma and Epstein-Barr virus: high frequency of EBV-infection in T-cell lymphomas of Mexican origin

Epstein-Barr virus is universally associated with endemic Burkitt's lymphoma (BL) and undifferentiated nasopharyngeal carcinoma and can be detected in a significant proportion of cases of Hodgkin's disease (HD) and peripheral T-cell lymphoma, but only rarely in sporadic B-NHL. The frequency of EBV-positivity in certain neoplasms shows important geographic variations. Both HD and sporadic BL from Latin America have shown higher rates of EBV-association than cases from Western countries. In T-NHL, the frequency of EBV-positivity is influenced by the site of the primary tumor and the phenotype of the neoplastic cells. Nasal and nasal-type T-NHL, which show a T/NK-cell phenotype with expression of CD56 are virtually always EBV-associated, whereas only a proportion of nodal, gastrointestinal and pulmonary T-NHL are EBV-infected. A recent investigation of primary intestinal lymphomas of Mexican origin demonstrated EBV-positivity in all examined cases of T-NHL and BL and a proportion of other B-NHLs. The presence of EBV was independent of the presence or absence of enteropathy. Two of 6 cases studied showed CD56 expression. The high rate of EBV-positivity independent of histologic subtype is in contrast to the low to intermediate rates of EBV-positivity found in cases of intestinal T-NHL from Western countries and indicates that geographic differences in the frequency of EBV-association of lymphoid neoplasms might also extend to a fraction of peripheral T-cell lymphomas.

Rank dependent seasonal levels of IGF-1, cortisol and reproductive hormones in male pudu (Pudu puda)

We tested the following hypothesis: when two pudu males share a single pen throughout the year, the dominant animal will have a higher level of IGF-1 than its subordinate pen mate, particularly during the period of increased social friction (e.g. rut and establishment of territories). To test this hypothesis, we used data from six adult males maintained at the University of Concepión, Chile (latitude 36.6 degrees S), and analysed them from the males' dominance point of view. Two males plus eight to ten females were kept in one pen and although we did not specifically measure dominance, the rank position was obvious from frequent encounters between the bucks. Three consecutive blood samples were taken monthly over the period of 1 year. In addition to IGF-1, we also analysed seasonal levels of testosterone, cortisol, prolactin, LH and FSH. The analysis revealed that IGF-1 levels of dominant males were significantly higher than those of subordinate males from September to November (the second part of the antler growing period and time of establishing territories). Testosterone levels were higher and FSH levels were lower in dominant males during the rut. Levels of prolactin were higher in dominant animals in November (summer). Cortisol and LH did not show any significant differences between dominant and subordinate males. This data provides the first evidence indicating the possible link between dominance and blood levels of IGF-1. The functional explanation of such links is discussed.

[Quality control of 135 histopathological reports of colo-rectal carcinoma]

OBJECTIVE

To evaluate the information content in our surgical pathology reports of colon and rectum carcinoma.

SETTING

A third level hospital.

DESIGN

Consecutive surgical reports from 1988 to 1994 were retrieved. The gross and histological variables with prognostic relevance according to the TNM system were registered using a checklist with standardized variables as proposed by two groups of pathologists. The adequacy of our reports was surveyed counting the number of histopathological variables in relation to the 11 prognostic parameters that must be included in routine surgical reports of large colon carcinomas.

RESULTS

The surgical reports were 135. The histologic type, tumor grade and histological tumor invasion were provided in most of the reports. In 90% the lymph node characteristics were described and 85% had gross and histologic margin assessment. But other variables were poorly informed, i.e. vascular invasion was informed in one case (0.7%).

CONCLUSIONS

Our surgical reports were considered adequate as 113/135 (84%) recorded more than eight prognostic variables. Insufficient data were: 1) a poor gross description; 2) lack of tumor grading in 12%; and 3) omission of anatomic site in 29%.

Post-transplantation lymphoproliferative disorders in Mexico: an aggressive clonal disease associated with Epstein-Barr virus type A

Post-transplantation lymphoproliferative disorders (PT-LPDs) are a complication of immunosuppression with variable clinical behavior and frequent Epstein-Barr virus (EBV) association. There is geographic variation in the association of EBV with certain tumors and a lack of studies of PT-LPDs from developing countries, so we decided to study in detail a series of PT-LPDs from Mexico to identify similarities and differences between populations in Mexico and those in Europe and the United States. We used paraffin-embedded tissue from eight PT-LPDs (six from men, two from women) that arose after renal transplantation. Clinical data, morphologic features, and clonality on the basis of immunoglobulin (Ig) light chain restriction, as well as polymerase chain reaction (PCR) for Ig heavy chain genes, were studied. The presence of EBV was investigated with PCR, immunohistochemical analysis for latent membrane protein (LMP)-1, and in situ hybridization for EBV early RNA transcripts. In addition, the subtype of EBV based on the EBNA 2A and 2B genes and the presence of a 30-bp deletion in the LMP-1 gene were investigated by PCR. Seven (87.5%) of eight cases presented with gastrointestinal involvement; five patients died. Three cases were polymorphic PT-LPDs, four were monomorphic large cell lymphomas (one diffuse large cell, three immunoblastic), and one was unclassifiable. All showed a B-cell phenotype, with a clonal population demonstrated in seven of the eight cases. Tumor cells expressed EBERs in all of the cases and LMP-1 in six of seven evaluable cases. Seven of seven cases showed EBV subtype A. Two (25%) of eight cases had the 30-bp LMP-1 deletion. This study shows that PT-LPDs in Mexico are clonal disorders associated with EBV subtype A. In contrast to series from Europe and the United States, our cases showed a significantly higher incidence of gastrointestinal tract involvement (P < .001), and a lower incidence of the 30-bp LMP-1 deletion, although this was not statistically significant (P < .28).

Altered pattern of cytokine production by peripheral blood CD2+ cells from B chronic lymphocytic leukemia patients

To determine if activation-induced cytokine production is altered in CD2+ lymphocytes from B-CLL patients, cytokine levels were determined by ELISA in supernatants of PHA-stimulated cultures of CD2+ cells from 33 B-CLL patients and 22 healthy controls. The production of Interferon gamma (IFN-gamma) and Tumor Necrosis Factor (TNF-alpha) by mitogen-activated CD2+ lymphocytes from B-CLL patients was higher than that found in healthy controls, while no differences were found in TNF-beta production. IFN-gamma and TNF-alpha levels determined at 72 h in PHA-stimulated CD2+ cell cultures from B-CLL patients statistically correlated with the percentages of CD3+CD45RO+ and CD3-CD56+ lymphocytes, respectively. Although there were differences in the production kinetics of interleukins (ILs) 2 and 4 between B-CLL patients and the healthy controls, no differences were found at the time when the levels of both interleukins peak. The production of both IFN-gamma and IL-4 by PHA-stimulated CD2+ lymphocytes from non-smouldering B-CLL patients was significantly higher than that from smouldering B-CLL patients while no significant differences were found in the production of IL-2, TNF-alpha, and TNF-beta between the two B-CLL patient groups. These data suggest that functional alterations in the production of cytokines by CD2+ cells from B-CLL patients could help to explain the expansion of leukemic cells in B-CLL patients.

Study of the diagnostic value of strontium, chloride, haemoglobin and diatoms in immersion cases

Tests of haemoglobin (Hb), strontium (Sr) and chloride (Cl), as well as diatoms, toxicological and pathological studies were performed in biological samples from 133 immersion fatalities occurred since 1991 to 1996 in central and northern Spain. Hb, Sr, and Cl where analyzed in blood samples where increasing decomposition could be demonstrated in most of the cases. The samples were frequently accompanied with well documented forensic reports, including autopsies findings and other circumstances of the death. The goal of our study is to evaluate the difference of blood Sr concentration between the left and right side of the heart (LVSr-RVSr) as a marker of drowning. For this purpose, the cases investigated were classified in 'typical drowning' (TD) cases and 'atypical drowning' (AD) cases. This last group was used as a control. The comparison of the LVSr-RVSr between TD and AD cases was highly significant (P = 0.0002) in blood specimens extracted from cases occurred in putative drowning media where Sr concentration was higher than 800 micrograms/l. No significant differences were found comparing neither Cl nor Hb biventricular concentrations between TD and AD cases in blood samples extracted from bodies found in both fresh and seawater.

Morphological variants of leukemic cells in B chronic lymphocytic leukemia are associated with different T cell and NK cell abnormalities

B chronic lymphocytic leukemia (B-CLL) is a heterogeneous disease. The different morphological variants of leukemic B cells appear to define different clinical groups of patients. Several abnormalities have been found in T lymphocytes and natural killer (NK) cells from B-CLL patients. We have investigated the phenotypic and functional characteristics of purified CD2+ cells from B-CLL patients at Binet's stage A and classified according to the neoplastic B lymphocyte morphology criteria: 32 patients with typical B-CLL and 12 patients with atypical B-CLL. Forty-three age and sex matched healthy controls were also studied. In fresh purified CD2+ cells from typical B-CLL patients, percentages of CD4+, CD4+CD45RA+, CD8+CD45RA+ T lymphocytes and CD3-CD56+ (NK) cells were significantly higher than those found in atypical B-CLL patients. However, in DC2+ cells from typical B-CLL patients, percentages of CD3+, CD3+DR+, CD8+, CD4+CD45RO+, and CD3+CD56+ cells were significantly lower than those found in atypical B-CLL patients. Increased percentage of NK cells was only found in typical B-CLL patients. The proliferative response and the production of interleukin (IL)-2 and IL-4 by phytohemagglutinin (PHA) stimulated CD2+ cells were significantly higher in typical B-CLL patients than in atypical B-CLL patients. We concluded that different patterns of phenotypic and functional alterations in the T lymphocytes and NK cells of B-CLL patients are found in patients with typical or atypical B-CLL defined according to the morphology of the leukemic cells.