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PubMed2003

Is there still an indication for nursing patients with prolonged neutropenia in protective isolation?. An evidence-based nursing and medical study of 4 years experience for nursing patients with neutropenia without isolation.

UNLABELLED: Patients with severe neutropenia due to high-dose chemotherapy and/or total-body irradiation are at risk of serious infections and are frequently nursed in strict protective isolation. This is a costly procedure and results in a psychological burden for the patient and its significance has been debated for a long time. The introduction of very potent systemic antibiotics, antibiotic prophylaxis, haematopoietic growth factors and peripheral stem cell transplantation might have decreased the need for it. We performed a systematic literature review and conducted a medical/nursing guideline study. In the literature we searched especially for prospective randomised studies. Only six were found, these were prospective randomised studies and contradicted each other on the usefulness of protective isolation. In an initiative aimed at promoting evidence-based care, we conducted a combined medical and nursing guideline study consisting of three parts: (1) inventory of (inter) national guidelines; (2) analysis of potential sources of infection; and (3) follow-up study post-implementation of new guidelines. RESULTS: (1) The practices in different centres in Europe appeared to vary widely. (2) Micro-organisms spread easily, especially if hands are not adequately dried. Isolation does not prevent this. Based on these findings we decided to stop protective isolation. This change of policy was combined with a campaign for optimal hygiene and introduction of hand alcohol. (3) We monitored the incidence of febrile neutropenia, infections and use of systemic antibiotics and antifungals in a 3-year period without protective isolation and compared this with the findings in the preceding 3 years with isolation. No significant differences in infections and mortality were found. We concluded that abandoning protective isolation combined with increased hygienic measures in nursing of patients with severe neutropenia does not increase the risk of infections, but improves the quality of care and patient satisfaction and reduces costs.

Adult↗
PubMed1993

European isolation and confinement study. Attention during isolation and confinement.

The aim of this study was to examine the effect of isolation and confinement on selective attention. The experiments were carried out on six specially selected male subjects. The subjects were isolated in a hyperbaric chamber complex at a low overpressure for a period of 28 days. Distribution of attention between two tasks, visual search and orientation of attention to symbolic and automatic cues were studied. The results showed that 4 weeks of isolation and confinement do not significantly modify visual search and the capacity to execute two tasks simultaneously. In the double task experiment there was a clear improvement of performance during isolation and the post-isolation period. However, the development of a remarkably large difference between subjects was found. Orientation of attention to automatic cues gave results comparable to those obtained under normal conditions. Valid trials (stimulus flash and cue in same box) were faster than both neutral (cue in all boxes) and invalid trials (stimulus flash and cue in different boxes). Orientation of attention to symbolic cues also produced this effect. However, the "meridian effect" (increased reaction time when the stimulus is in the opposite half of the visual field as cue), which is constantly observed under normal conditions, was absent during isolation. The absence of the meridian effect is interpreted as a change in the subject's strategy to allocate attention. It is proposed that the absence of the meridian effect indicates an initial deficit of attentional capacities during isolation and confinement.

Adult↗
PubMed1996

Calcium content and respiratory control index of isolated skeletal muscle mitochondria: effects of different isolation media.

Calcium (Ca) content measured with graphite furnace atomic absorption spectrometry and polarographical measurement of respiratory control index (RCI) were performed on isolated skeletal muscle mitochondria. Four different isolation media were used in order to develop a method for isolating physiologically intact mitochondria in small samples with an endogenous Ca content as close as possible to in vivo conditions. With ruthenium red in the isolation medium, the mean Ca content decreased fourfold to 19.3 +/- 6.8 nmol/mg protein and RCI increased about 25% to 6.9 +/- 1.1 compared with a standard medium. With EGTA or EGTA plus ruthenium red, the mean Ca content decreased further to 5.8 +/- 1.0 and 5.1 +/- 0.9 nmol/mg protein and the mean RCI values increased to 8. 4 +/- 1.2 and 8.8 +/- 1.3, respectively. Isolated mitochondria from human muscle samples using EGTA and ruthenium red in the isolation medium had mean Ca values of 11.0 +/- 0.9 nmol/mg protein and mean RCI values of 12.2 +/- 1.6. The data indicate that the Ca concentration in the skeletal muscle mitochondria is inversely proportional to RCI, and the mitochondrial functional property is significantly improved upon lowering the intramitochondrial Ca accumulation by the incorporation of a chelating agent (EGTA) and a potent Ca antagonist, ruthenium red, in the isolation media.

Adult↗
PubMed2000

Guanarito virus (Arenaviridae) isolates from endemic and outlying localities in Venezuela: sequence comparisons among and within strains isolated from Venezuelan hemorrhagic fever patients and rodents.

Despite intensive surveillance, Venezuelan hemorrhagic fever (VHF), caused by Guanarito (GTO) virus, has been detected in only a small region of western Venezuela. To determine whether VHF is associated with a particular regional GTO virus strain(s), 29 isolates from rodents and humans throughout the surrounding regions were analyzed by partial sequencing of the nucleocapsid protein gene. Phylogenetic trees delineated nine distinct GTO genotypes that differ by 4-17% in nucleotides and up to 9% in amino acid sequences; most appeared to be restricted to discrete geographic regions, although a few genotypes were isolated in several locations. Each genotype included at least one strain recovered from a rodent, but only two genotypes were isolated from VHF cases. The presence outside of the endemic/epidemic region of two genotypes isolated also from VHF cases suggests that human pathogenic viruses occur outside of the endemic zone, but do not frequently infect people and/or cause apparent disease there. VHF does not appear to be associated with a GTO virus genotype that is restricted to a certain rodent species. When quasispecies diversity was examined, rodent isolates had higher sequence variation than human isolates. One rodent isolate included a mixture of two phylogenetically distinct genotypes, suggesting a dual infection.

Animals↗
PubMed2000

Isolation, cloning, and complete nucleotide sequence of a phenotypically distinct Brazilian isolate of human T-lymphotropic virus type II (HTLV-II).

Analysis of human T-lymphotropic virus type II (HTLV-II) isolates from North America and Europe have demonstrated the existence of two molecular subtypes of the virus, HTLV-IIa and HTLV-IIb. Recently, studies on HTLV-II infections in Brazil have revealed isolates that are related phylogenetically to the HTLV-IIa subtype but have a HTLV-IIb phenotype with respect to the transactivating protein, tax. To more clearly define this relationship, HTLV-II was isolated from peripheral blood of an IVDA from Sao Paulo, Brazil (SP-WV), and the complete provirus was cloned and sequenced. Comparison of HTLV-II(SP-WV) nucleotide sequences to other available complete HTLV-II proviral sequences revealed that HTLV-II(SP-WV) is most closely related to HTLV-II(Mo), the prototypic HTLV-IIa subtype sequence. Phylogenetic analysis of LTR, env, and tax regions unequivocally demonstrated that HTLV-II(SP-WV) and all other Brazilian sequences examined are members of the IIa subtype. The predicted amino acid sequences of the major coding regions of HTLV-II(SP-WV) are also most closely related to HTLV-II(Mo), with the important exception of tax. The tax protein encoded by HTLV-II(SP-WV) is 96-99% identical to the tax of IIb isolates and is similar in that it has an additional 25 amino acids at the carboxy-terminus compared to the HTLV-II(Mo) tax with which it shares 91% identity. Analysis of tax stop codon usage of a number of HTLV-IIa isolates from North American, Europe, and Brazil demonstrated that isolates from the last region appear to be unique in their extended tax phenotype. It could be demonstrated that the extended tax proteins in the HTLV-IIb and Brazilian isolates had equivalent ability to transactivate the viral LTR, and studies with deletion mutants indicated that the extended C-terminus is not essential for transactivation. In contrast, the HTLV-IIa tax was found to have a greatly diminished ability to transactivate the viral LTR, which appeared to be a consequence of reduced expression of the protein. The studies show that although the Brazilian strains do not represent an entirely new subtype based on nucleotide sequence analysis they are a phenotypically unique molecular variant within the HTLV-IIa subtype.

Brazil↗
PubMed1996

Complete nucleotide sequence of the Japanese isolate S of beet necrotic yellow vein virus RNA and comparison with European isolates.

The complete nucleotide sequences of beet necrotic yellow vein virus RNA-1 to RNA-4 of the Japanese isolate S (BNYVV-S) were determined and compared with those of French isolate (BNYVV-F2). The nucleotide sequences of the two isolates were very similar, differing by only 1.7% (RNA-1), 4.1% (RNA-2), 2.9% (RNA-3) and 3.6% (RNA-4), respectively. The differences of the amino acid sequences of the two isolates depended upon the open reading frames (ORF) as follows: P237, 1.4%; P22 (coat protein), 2.1%; 54k ORF, 3.4%; P42, 0.5%; P13, 1.7%; P15, 3.0%; P14, 7.0% P25, 6.4%; P31, 3.5%. Comparison of the coat protein and triple gene block (P42, P13 and P15) regions of RNA-2 with other isolates revealed that BNYVV-S was much more similar to the Yugoslavian isolate (BNYVV-Yu2) than to BNYVV-F2. The nucleotide differences between BNYVV-S and BNYVV-Yu2 were less than 1%. Based upon the grouping of BNYVV variants reported by Kruse et al. [10], BNYVV-S is thus considered to belong to the A type along with BNYVV-Yu2, whereas BNYVV-F2 is classified in the B type. Our data suggest that the Japanese isolate S may have been derived from European countries other than France or Germany.

Amino Acid Sequence↗
PubMed2001

The partial sequencing of the genomic RNA of a UK isolate of Pepino mosaic virus and the comparison of the coat protein sequence with other isolates from Europe and Peru.

A 3599 nucleotide portion of the genomic RNA of a UK isolate of Pepino mosaic virus (PepMV), isolated from tomato, has been sequenced (Accession No. AF340024). The region sequenced includes the 3'-end of the RNA polymerase, the triple gene block (TGB), the coat protein (CP) and 3' untranslated region (UTR). In addition, the CP sequences of another 15 PepMV isolates, including 14 European tomato isolates and a Peruvian pepino isolate, have been determined and compared. This analysis shows that all the tomato isolates share over 99% identity, but only between 96-97% identity with the Peruvian pepino isolate.

Amino Acid Sequence↗
PubMed2006

Serotype and antimicrobial resistance patterns of Streptococcus pneumoniae isolated from Taiwanese children: comparison of nasopharyngeal and clinical isolates.

This report describes the serotypes and antimicrobial resistance patterns of 860 strains of Streptococcus pneumoniae isolated from nasopharyngeal (NP) carriers and clinical specimens collected from Taiwanese children during the years 1997 to 2003. The 6 most common serotypes/groups were 23F, 19F, 6B, 14, 6A, and 3. These accounted for 652/716 (91.1%) of the NP and 131/144 (91.0%) of the clinical isolates. Serotype 23F was the most common isolate in the NP carriers (25.7%, 184/716). Serogroup14 was most common in the clinical isolates (29.2%, 42/144) and the most frequent invasive isolate (43.4%, 33/76). It was more frequently associated with invasive infection than all other serotypes/groups (odds ratio = 7.2; 95% confidence interval, 4.16-12.46; P < .0001). Resistance to macrolides was high in all serotypes/groups, which ranged from 70% to 97%. Resistance to penicillin varied among the 6 leading serotypes/groups, ranging from 3% in serogroup 3 to 99% in serotype 19F. Serotype 23F was most likely to be multidrug resistant to penicillin, macrolides, and chloramphenicol compared with all others (107/150 [71%] versus 105/461 [23%], P < .0001). The potential coverage by the pentavalent and heptavalent vaccines was 83% for all isolates, but was significantly lower for NP than clinical isolates (81% versus 92%, P< .01). These findings provide baseline data to compare trends in the distribution of pneumococcal serotypes and antibiotic resistance patterns with the introduction of childhood pneumococcal vaccination in Taiwan and other countries.

Adolescent↗
PubMed2006

Left superior vena cava isolation in patients undergoing pulmonary vein antrum isolation: impact on atrial fibrillation recurrence.

BACKGROUND: A persistent left superior vena cava (SVC) can be an arrhythmogenic source in patients with atrial fibrillation (AF) through connections from the coronary sinus (CS) and the left atrium (LA). The left SVC can be electrically isolated. However, little clinical data about the impact of left SVC disconnection on AF outcome are available. We report on six patients with left SVC and recurrent AF. OBJECTIVES: The purpose of this study was to assess the impact of left SVC isolation on AF recurrence. METHODS: Six patients (4 men and 2 women; age 50 +/- 6.4 years) with symptomatic drug-refractory AF and persistent left SVC presented to our laboratory for treatment. Four of the patients had left SVC isolation only because there was no conduction recovery in the pulmonary veins (PVs) after several previous procedures. RESULTS: Conduction between the left SVC and the CS and LA was documented, as was spontaneous ectopies in three patients that degenerated into AF in one patient. Isolation of the left SVC was successful in all patients. Isolation was relatively easy to perform (10.25 +/- 1.6 minutes), with no complications. After follow-up of 13 +/- 7.4 months, all patients were in sinus rhythm and free from AF without antiarrhythmic drugs. CONCLUSION: This study stresses the importance of looking for unusual sources of AF in patients presenting for repeat procedures or in those in whom the PVs have been ruled out as a source triggering AF. We present clinical evidence that in patients with AF and left SVC, isolation of the PVs only may not be sufficient to suppress AF. Thus, diagnosis and isolation of the left SVC appears critical to preventing AF recurrence in patients with AF when ablation is considered.

Atrial Fibrillation↗
PubMed2004

Beta-lactam susceptibilities and prevalence of ESBL-producing isolates among more than 5000 European Enterobacteriaceae isolates.

In vitro susceptibility to 15 beta-lactam antibiotics was evaluated using Enterobacteriaceae isolated during the SENTRY Antimicrobial Surveillance Program. Piperacillin/tazobactam was the most active penicillin against Escherichia coli, Proteus mirabilis, Klebsiella oxytoca and Klebsiella pneumoniae (94.9%, 98.3%, 87.4% and 82.9% of isolates susceptible). Of the cephalosporins, cefepime was most effective against Escherichia coli, Proteus mirabilis and Enterobacter cloacae (99.2%, 96.3% and 95.2% of isolates susceptible, respectively) and cefoxitin against Klebsiella oxytoca and Klebsiella pneumoniae (98.6% and 95.6% of isolates susceptible). Carbapenems had excellent activity (> or =99.5% of all isolates). ESBL-production was confirmed with the ESBL-Etest and disk diffusion test in 1.3% of Escherichia coli isolates, 18.4% of Klebsiella pneumoniae, 12.6% of Klebsiella oxytoca and 5.3% of Proteus mirabilis isolates.

Aztreonam↗
PubMed1994

[Characterization of fungi isolated from woody-chip piles, especially thermophilic and thermotolerant isolates].

Samples were taken in order to isolate fungi from four woodychip piles (three of these were treated with liquid manure) from different depths. 39 species of 121 isolates could be determined. They represent 28 genera. Aspergillus fumigatus, Trichoderma reseei, Corynascus sespedonium and Mucor hiemalis were isolated most frequently. The isolates were examined for their temperature requirements. Following the definitions of Hawskworth (1983) they could be classified into the three groups of "thermophilic" (28 isolates), "thermotolerant" (29 isolates) and "mesophilic" (64 isolates) fungi. The temperature requirements for sporulation were also examined. Partly sporulation could be observed within more restricted temperature borders than growth but optimal sporulation occurs within wider temperature areas than optimal growth. The optimal sporulation-temperature was defined as the temperature at which sporulation began fastest.

Fungi↗
PubMed2003

Isolation of Mycoplasmas from nasal swabs of calves affected with respiratory diseases and antimicrobial susceptibility of their isolates.

Nasal swabs of 293 calves were examined for Mycoplasma. The samples were collected from calves affected with respiratory diseases on 71 farms in various parts of Japan between 1996 and 1997. Mycoplasma bovirhinis was isolated from 47 of 293 calves (16.0%). Mycoplasma alkalescens, M. bovis, M. arginini, M. bovigenitalium and Acholeplasma spp. were isolated from 19 (6.5%), seven (2.4%), four (1.4%), four (1.4%) and 18 (6.1%) calves, respectively. Pasteurella multocida and P. haemolytica were isolated from 60% of Mycoplasma-positive calves. However, other bacteria were not isolated from calves. To evaluate the antimicrobial susceptibility of their isolates, 68 M. bovirhinis, 21 M. alkalescens and 10 M. bovis strains were examined for 12 antimicrobial agents. All isolates showed higher susceptibility to tiamulin than to the other drugs used in the study. However, erythromycin had no effect on any of the Mycoplasma strains studied. The field isolates were less susceptible than the type strains to some drugs, such as spiramycin, oxytetracycline and tylosin.

Animals↗
PubMed2000

Bordetella holmesii isolated from a patient with sickle cell anemia: analysis and comparison with other Bordetella holmesii isolates.

OBJECTIVES: To analyze a Bordetella holmesii isolate from a patient with sickle cell anemia and to compare it with other B. holmesii strains and isolates and with strains of B. pertussis and B. bronchiseptica, two well-characterized species of the Bordetella genus. METHODS: The bacteriological characteristics and proteins produced by the B. holmesii isolate and the reference strain (ATCC 51541) were analyzed and compared with those of B. pertussis and B. bronchiseptica using sera from patients infected with B. pertussis, B. bronchiseptica or B. holmesii. RESULTS: The bacteriological characteristics of the B. holmesii isolate studied here were similar to those of the B. holmesii reference strain and other isolates. Some of the proteins produced by B. holmesii isolates were similar to those produced by B. pertussis and B. bronchiseptica, but none of these proteins was similar to the toxins and adhesins involved in the pathogenicity of B. pertussis and B. bronchiseptica. The phenotypic diversity of the proteins produced by B. holmesii isolates and the reference strain was striking. CONCLUSIONS: Our results suggest that either, the expression of B. holmesii proteins is regulated as in B. pertussis and B. bronchiseptica, with the B. holmesii strain exhibiting different phases, or the proteins produced in B. holmesii are different.

Adhesins, Bacterial↗
PubMed2005

Left atrial flutter following pulmonary vein antrum isolation with radiofrequency energy: linear lesions or repeat isolation.

INTRODUCTION: Left atrial flutter (LAFL) is a known complication of pulmonary vein isolation. Treatment of this arrhythmia currently involves both linear lesions as well as re-isolation. However, it is unknown if re-isolation alone is sufficient to prevent recurrence. This study reviews the incidence of LAFL following segmental PV antrum isolation (PVAI) in a large patient population and evaluates if re-isolation alone is sufficient to prevent recurrence. METHODS AND RESULTS: Seven hundred thirty-seven patients underwent PVAI. Twenty-three patients (3.1%) developed post-PVAI LAFL. All patients underwent a second procedure in which only repeat PVAI was done. During the second procedure, all flutter circuits were electroanatomically mapped. All patients were followed at 3, 6, and 12 months. All 23 patients demonstrated recovery in one or more PV. After repeat isolation of the PVs, 61% of patients were arrhythmia free off all antiarrhythmic drugs. A relationship between the presence/absence of pre-existing left atrial (LA) scar was observed. Of the 11 patients with pre-existing LA scar, 36% remained arrhythmia free off antiarrhythmic drugs. In contrast, of the 12 patients without pre-existing LA scar, 83% remained arrhythmia free off antiarrhythmic drugs (P = 0.03). CONCLUSION: Among patients with LAFL following PVAI, re-isolation alone is sufficient in preventing recurrence in patients without pre-existing LA scar. Patients with pre-existing LA scar tend to have recurrence requiring further ablation including linear lesions, and continue to need antiarrhythmic medications.

Atrial Fibrillation↗
PubMedDate not supplied

Production of muraminidase-released protein (MRP), extracellular factor (EF) and suilysin by field isolates of Streptococcus suis capsular types 2, 1/2, 9, 7 and 3 isolated from swine in France.

A total of 323 isolates of Streptococcus suis recovered from diseased or healthy pigs in France were serotyped. The presence of virulence-related proteins, Muraminidase-Released Protein (MRP), Extracellular Factor (EF) and Suilysin was also studied in 122 isolates of capsular types 2, 1/2, 9, 7 and 3 to evaluate their implication in virulence of S. suis. Capsular types 2, 1/2, 9, 7 and 3 were the most frequently detected (93%), with 69% for the capsular type 2 alone. Capsular types 2, 1/2, 9, 7, 3, 1, 4, 8, 18, 10 and 12 were isolated from diseased pigs, whereas types 2, 7, 9, 1/2, and 3 originated from the nasal cavities or tonsils of healthy animals. Most of the S. suis type 2 isolates recovered from diseased pigs carried MRP+ EF- Suilysin- (46%) or MRP+ EF+ Suilysin+ (28%) phenotypes. The MRP+ EF- Suilysin- phenotype was also detected in 67% of S. suis type 2 strains isolated from healthy pigs. The production of the virulence-related proteins was less frequently found in S. suis types 1/2, 9, 7 and 3 recovered either from diseased or healthy pigs. In this study, all the capsular type 1/2 strains were MRP+ EF- Suilysin- and all the S. suis type 7 harboured an MRP- EF- Suilysin- phenotype. The MRP- EF- Suilysin- phenotype was found in S. suis types 2, 3, 7 and 9 isolated from septicaemia, meningitis, pneumonia, and pleurisy. These results suggest that the presence of these proteins should not be used as a single condition for classifying the virulence of a field isolate in France.

Animals↗
PubMed1998

The clinical indications for identical pathogenesis of isolated and non-isolated testicular relapses in acute lymphoblastic leukaemia.

In the present population-based study, we compared the clinical data of testicular relapses with and without concurrent bone marrow relapse and clinical data of the relapses in other locations among boys with acute lymphoblastic leukaemia (ALL), in order to study the possible evidence of early sequestration and local regulation of leukaemic lymphoblast in the testis of humans. The results suggest that the pathogenesis of isolated testicular relapse (T) and testicular relapse with a concurrent bone marrow relapse (T + BM) is likely to be similar. Isolated and non-isolated testicular relapses appeared late after the achievement of remission (T 34 +/- 16 months, T + BM 32 +/- 15 months) in ALL compared to relapses in other locations (CNS 23 +/- 11 months, BM 25 +/- 19 months). The better prognosis after testicular relapses (estimated second event free survival probability, 2-EFS: T 0.63, T + BM 0.32) compared to bone marrow relapse (2-EFS: BM 0.13) further suggests that testicular relapse with a concurrent bone marrow relapse possibly originates from the isolated testicular relapse, and that the isolated testicular relapse is a separate entity and not a manifestation of systemic recurrence. Higher frequencies of isolated and non-isolated testicular relapses (T 9%, T + BM 5%) were observed among boys with onset of ALL in early puberty (10-12 y) compared to those among younger (T 4%, T + BM 2%) and older (T 0%, T + BM 0%) boys. The late occurrence, the possible association with hormonal maturation and the good prognosis after testicular relapses suggest a possible local regulation of the residual leukaemic lymphoblast in human testis.

Adolescent↗
PubMed2000

Genomic differences in Streptococcus pyogenes serotype M3 between recent isolates associated with toxic shock-like syndrome and past clinical isolates.

Genomic differences among past Streptococcus pyogenes serotype M3 strains isolated in 1973 and before from patients with streptococcal pharyngitis, recent (1990s) serotype M3 clinical isolates from patients with pharyngitis, and recent M3 isolates from patients with toxic shock-like syndrome were investigated by restriction landmark genomic scanning and by modified random-amplified polymorphic DNA-polymerase chain reaction. Similar polymorphic DNA fragments were identified between the older M3 isolates and the recent isolates; also, the recent M3 clinical isolates from patients with pharyngitis were genetically indistinguishable, by the methods used, from the M3 isolates of patients with toxic shock-like syndrome. Although nucleotide sequences of these regions showed no apparent homology with known virulence factors, the DNA fragments could distinguish the recent M3 strains from the past strains. These results suggested that the recent strains have emerged because of genetic divergence.

Humans↗
PubMed2004

HIV type 2 primary isolates induce a lower degree of apoptosis "in vitro" compared with HIV type 1 primary isolates.

To determine whether subtypes of HIV-1 and HIV-2 vary in their ability to induce T cell apoptosis in vitro, human peripheral blood mononuclear cells (PBMC) from healthy donors and CEM.NKR-CCR5 cells were infected with a variety of HIV-1 and HIV-2 isolates in vitro. Apoptotic cell levels and chemokine and cytokine production were analyzed. Significant variations in cytopathic effects following in vitro infection with primary isolates of HIV-1 or HIV-2 subtypes were observed in PBMCs. The percent of apoptotic cells from each individual ranged from 2 to 78% after HIV-1 infection and from 0 to 28% after HIV-2 infection (p < 0.01). We did not observe significant differences in the degree of apoptosis induced among cells infected with different HIV-1 group M subtypes or group O virus, nor among cells infected with different HIV-2 isolates. However, HIV-2 induced significantly lower degree of apoptosis overall in PBMC and CEM.NKR-CC5 cells when compared with HIV-1 subtypes (p < 0.0001). No significant differences were observed in the production of chemokines, such as RANTES, MIP-1alpha, and MIP-1beta, and cytokines, such as TNF-alpha and TNF-beta when PBMC cultures were infected with different HIV-1 subtype viruses, or HIV-2 isolates. In conclusion, HIV-2 isolates induced significantly lower levels of T cell apoptosis in both PBMC and CEM.NKR-CCR5 cells than HIV-1 isolates. No differences in T cell apoptosis levels were seen between different subtypes of HIV-1 group M or group O isolates. This is consistent with the mild clinical course of infection with HIV-2 that has been reported relative to that observed with HIV-1.

Apoptosis↗