Pulmonary manifestations of AIDS: review of 106 episodes

We reviewed the clinical records and chest radiographs of all patients admitted to our institution between 1982 and 1984 who had pulmonary disease and who were later proved to have acquired immunodeficiency syndrome (AIDS) (95 patients). Diffuse parenchymal lung disease was the most common finding. These infiltrates were usually interstitial and caused by Pneumocystis carinii pneumonia or P. carinii combined with cytomegalovirus infection. Focal, multilobar, interstitial infiltrates were also often seen and usually caused by P. carinii or P. carinii and cytomegalovirus infections. Rarely, well-defined, multiple, interstitial nodules less than 10 mm in diameter were the only or predominant characteristic and were seen only in association with Mycobacterium tuberculosis or Cryptococcus neoformans infections or Kaposi sarcoma. Hilar or mediastinal adenopathy occurred in 17 of the 21 patients with M. tuberculosis or C. neoformans infections. In contrast, only 4% of patients with P. carinii infections presented with these findings. We also found that hilar or mediastinal adenopathy was not significantly associated with peripheral adenopathy. Lung cavitation, pleural effusion, or a normal chest radiograph was uncommon.     

Differential effects of mepacrine, chloroquine and hydroxychloroquine on superoxide anion generation, phospholipid methylation and arachidonic acid release by human blood monocytes

The 4-aminoquinolines chloroquine (CQ) and hydroxychloroquine (HCQ), and previously the 9-aminoacridine mepacrine (quinacrine) (MP), have been widely used in the treatment of inflammatory disorders such as rheumatoid arthritis and systemic lupus erythematosus. Their effects are believed to be mediated through phagocytic cells but the precise biochemical basis remains uncertain. We have investigated the effects of these drugs on monocyte superoxide anion (SO) generation elicited by 5 different stimuli-opsonised zymosan (STZ), FMLP, A23187, TPA and fluoride--and sought correlations with effects on two processes which have been linked with monocyte activation, namely arachidonate (AA) release and transmethylation of phosphatidyl ethanolamine (PE) to phosphatidylcholine (PC). In all experiments conditions were adjusted to achieve leucocyte concentrations of drug comparable to those found during in vivo therapy. Neither CQ nor HCQ had any marked effect on SO release induced by TPA, A23187 or fluoride ion, excluding a significant effect on protein kinase C (PKC), calmodulin-dependent kinase(s) or the membrane-bound, superoxide generating NADP(H) oxidase. In contrast MP inhibited the response to TPA and A23187. Each drug also had different effects on surface receptor-dependent responses; thus HCQ inhibited FMLP- but not STZ-induced SO release, whereas CQ and MP inhibited the response to both stimuli. Each drug also displayed different effects on AA release and phospholipid (PL)-methylation; MP and HCQ, but not CQ, inhibited STZ-stimulated AA release while MP and CQ but not HCQ inhibited basal rates of PL-methylation in mononuclear cells (MNC). However, only MP inhibited PL-methylation in an enriched monocyte population. We conclude that despite their close structural similarity, MP, CQ and HCQ each have different metabolic effects and their actions cannot simply be attributed to inhibition of lysosomal functions. Other possible mechanisms of action are discussed. The selective effects of each drug also provide further evidence for multiple pathways of monocyte activation.     

Venezuelan equine encephalitis virus vectors expressing HIV-1 proteins: vector design strategies for improved vaccine efficacy

A live virus vaccine vector has been constructed from a molecularly cloned attenuated strain of Venezuelan equine encephalitis virus (VEE). High levels of foreign protein expression are regulated by an additional copy of the 26 S viral subgenomic RNA promoter. The position of this additional promoter and foreign gene in the VEE genome was predicted to have a major influence on expression level of the heterologous protein. Two sites in the genome were tested to determine the optimal site for expression of the matrix/capsid (MA/CA) coding region of human immunodeficiency virus (HIV-1). One vector contained the additional promoter and the MA/CA genes immediately downstream of the VEE E1 gene at the 3' end of the genome. In the second vector, the additional promoter was introduced immediately upstream from the authentic 26 S subgenomic promoter. Significantly higher levels of MA/CA were expressed from the downstream vector compared to the upstream vector. However, the stability of expression for both vectors was similar following passage in baby hamster kidney cells (BHK) cells. In BALB/c mice, the two vectors elicited similar levels of cellular immune responses to MA/CA as determined by bulk cytotoxic T-lymphocyte assays and precursor frequency analysis, but the humoral response induced by the downstream vector was significantly stronger. At 11 months post boosting with the downstream vector, serum antibody levels against HIV MA/CA were undiminished, and MA/CA specific CTLp were detectable in all mice tested. These findings suggest that VEE vectors can be optimized to elicit strong, balanced and long-lived immune responses to foreign viral proteins.     

In vitro and in vivo evaluations of a hydrophilic 64Cu-bis(thiosemicarbazonato)-glucose conjugate for hypoxia imaging

A water-soluble glucose conjugate of the hypoxia tracer 64Cu-diacetyl-bis(N4-methylthiosemicarbazone) (64Cu-ATSM) was synthesized and radiolabeled (64Cu-ATSE/A-G). Here we report our initial biological experiments with 64Cu-ATSE/A-G and compare the results with those obtained for 64Cu-ATSM and 18F-FDG. METHODS: The uptake of 64Cu-ATSE/A-G and 64Cu-ATSM into HeLa cells in vitro was investigated at a range of dissolved oxygen concentrations representing normoxia, hypoxia, and anoxia. Small-animal PET with 64Cu-ATSE/A-G was performed in male BDIX rats implanted with P22 syngeneic carcinosarcomas. Images of 64Cu-ATSM and 18F-FDG were obtained in the same model for comparison. RESULTS: 64CuATSE/A-G showed oxygen concentration-dependent uptake in vitro and, under anoxic conditions, showed slightly lower levels of cellular uptake than 64Cu-ATSM; uptake levels under hypoxic conditions were also lower. Whereas the normoxic uptake of 64Cu-ATSM increased linearly over time, 64Cu-ATSE/A-G uptake remained at low levels over the entire time course. In the PET study, 64CuATSE/A-G showed good tumor uptake and a biodistribution pattern substantially different from that of each of the controls. In marked contrast to the findings for 64Cu-ATSM, renal clearance and accumulation in the bladder were observed. 64Cu-ATSE/A-G did not display the characteristic brain and heart uptake of 18F-FDG. CONCLUSION: The in vitro cell uptake studies demonstrated that 64Cu-ATSE/A-G retained hypoxia selectivity and had improved characteristics when compared with 64Cu-ATSM. The in vivo PET results indicated a difference in the excretion pathways, with a shift from primarily hepatointestinal for 64Cu-ATSM to partially renal with 64Cu-ATSE/A-G. This finding is consistent with the hydrophilic nature of the glucose conjugate. A comparison with 18F-FDG PET results revealed that 64Cu-ATSE/A-G was not a surrogate for glucose metabolism. We have demonstrated that our method for the modification of Cu-bis(thiosemicarbazonato) complexes allows their biodistribution to be modified without negating their hypoxia selectivity or tumor uptake properties.     

Precise intraoperative location of gastrointestinal bleeding with a hand-held counter. Work in progress

The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.     

Anti-Sc1 in pregnancy

Anti-Sc1 was detected in a gravida-2 patient at 12 weeks' gestation. At 29 weeks, the antibody was found to be of the IgG3 subclass with a titer of 16, score 36, by the indirect antiglobulin test, and it produced 7 percent lysis by antibody-dependent cellular cytotoxicity (ADCC) assay, a finding that suggested an unaffected fetus. The titer remained constant throughout the pregnancy, as did the IgG subclass and activity in the ADCC assay. At delivery of the full-term infant, the cord hemoglobin was 13.5 g per dL and the direct antiglobulin test was positive (3+) with anti-IgG. The infant did not require transfusion. A sample taken 9 weeks after delivery showed 44 percent lysis in the ADCC assay. The anti-Sc1 titer was 32, score 65.     

Longitudinal study of urinary albumin excretion in young diabetic patients--Wessex Diabetic Nephropathy Project.

AIMS: This study was established to follow changes in albumin/creatinine ratio (ACR) and to determine the prevalence and degree of progression of microalbuminuria (MA) or of clinical proteinuria (CP) in children with Type 1 diabetes. The study has investigated subjects for up to 12 years in establishing the correlation between MA and gender, age, duration of diabetes and glycated haemoglobin (HbA1c). The study has defined clinical cut-offs for MA in daytime clinic urine samples in young diabetic subjects. METHODS: Three hundred and sixty-one patients were involved in the study, with 221 (61.2%) having over six sets of data. Urine samples were collected at routine annual clinic visits and analysed without prior freezing for ACR. Blood samples were taken for HbA1c measurement. Data including sex, age and duration of diabetes were recorded. RESULTS: A random clinic ACR of < 4.5 mg/mmol (males) and 5.2 mg/mmol (females) creatinine was used as the 'clinical cut-off' to define the presence of MA. The presence of MA was independent of HbA1c and duration of diabetes but appeared be associated with the adolescent years (> 10 years). There was little evidence of progression from normoalbuminuria to MA, or from MA to CP. Of patients aged 10-18 years, 30.9% of males and 40.4% of females had one or more episodes of MA. CONCLUSIONS: Persistent MA and random episodes of MA or CP may be associated with the adolescent years but not with duration of diabetes. Further study will reveal if the substantial increases in ACR sometimes seen during adolescence are predictive of diabetic nephropathy. Clinical cut-offs of < 4.5 and < 5.2 mg/mmol creatinine for males and females, respectively, are suggested for the interpretation of changes in ACR in random urine samples in young people with Type 1 diabetes.     

Development of the Antinuclear and Anticytoplasmic Antibody Consensus Panel by the Association of Medical Laboratory Immunologists

The Association of Medical Laboratory Immunologists (AMLI) have developed a panel of antinuclear and anticytoplasmic antibody consensus sera that can be useful for enzyme immunoassay (EIA), Ouchterlony, and immunofluorescence assay methods. It was developed to assist in the evaluation of newly available EIA methods for the detection of autoantibodies. The panel of sera was evaluated in several clinical laboratories and a large number of laboratories owned by manufacturers of clinical autoantibody testing kits. The majority of sera performed well for the EIAs in both the clinical laboratories and the manufacturers' laboratories, but some samples had discrepant results. A major source of discrepancy is the current inability of the EIA results to be directly compared in a quantitative way as no standardization exists. The evaluation demonstrated lower sensitivity of detection by the Ouchterlony method. The limited evaluation of the sera with immunoblotting and Western blotting did not show good agreement with other methods. Further work must be done to standardize blotting methods prior to their use in routine clinical testing. The sera are now available to vendors and clinical laboratories for use in the detection of SS-A, SS-B, Sm, U1-RNP, Scl-70, Jo-1, double-stranded DNA, and centromere antibodies. The availability of the consensus sera will help evaluate and improve the EIA methods currently being used.