Altered fear processing in adolescents with a history of severe childhood maltreatment: an fMRI study

BACKGROUND

Children with a history of maltreatment suffer from altered emotion processing but the neural basis of this phenomenon is unknown. This pioneering functional magnetic resonance imaging (fMRI) study investigated the effects of severe childhood maltreatment on emotion processing while controlling for psychiatric conditions, medication and substance abuse.

METHOD

Twenty medication-naive, substance abuse-free adolescents with a history of childhood abuse, 20 psychiatric control adolescents matched on psychiatric diagnoses but with no maltreatment and 27 healthy controls underwent a fMRI emotion discrimination task comprising fearful, angry, sad happy and neutral dynamic facial expressions.

RESULTS

Maltreated participants responded faster to fearful expressions and demonstrated hyper-activation compared to healthy controls of classical fear-processing regions of ventromedial prefrontal cortex (vmPFC) and anterior cingulate cortex, which survived at a more lenient threshold relative to psychiatric controls. Functional connectivity analysis, furthermore, demonstrated reduced connectivity between left vmPFC and insula for fear in maltreated participants compared to both healthy and psychiatric controls.

CONCLUSIONS

The findings show that people who have experienced childhood maltreatment have enhanced fear perception, both at the behavioural and neurofunctional levels, associated with enhanced fear-related ventromedial fronto-cingulate activation and altered functional connectivity with associated limbic regions. Furthermore, the connectivity adaptations were specific to the maltreatment rather than to the developing psychiatric conditions, whilst the functional changes were only evident at trend level when compared to psychiatric controls, suggesting a continuum. The neurofunctional hypersensitivity of fear-processing networks may be due to childhood over-exposure to fear in people who have been abused.

Grey matter volume and thickness abnormalities in young people with a history of childhood abuse

BACKGROUND

Childhood abuse is associated with abnormalities in brain structure and function. Few studies have investigated abuse-related brain abnormalities in medication-naïve, drug-free youth that also controlled for psychiatric comorbidities by inclusion of a psychiatric control group, which is crucial to disentangle the effects of abuse from those associated with the psychiatric conditions.

METHODS

Cortical volume (CV), cortical thickness (CT) and surface area (SA) were measured in 22 age- and gender-matched medication-naïve youth (aged 13-20) exposed to childhood abuse, 19 psychiatric controls matched for psychiatric diagnoses and 27 healthy controls. Both region-of-interest (ROI) and whole-brain analyses were conducted.

RESULTS

For the ROI analysis, the childhood abuse group compared with healthy controls only, had significantly reduced CV in bilateral cerebellum and reduced CT in left insula and right lateral orbitofrontal cortex (OFC). At the whole-brain level, relative to healthy controls, the childhood abuse group showed significantly reduced CV in left lingual, pericalcarine, precuneus and superior parietal gyri, and reduced CT in left pre-/postcentral and paracentral regions, which furthermore correlated with greater abuse severity. They also had increased CV in left inferior and middle temporal gyri relative to healthy controls. Abnormalities in the precuneus, temporal and precentral regions were abuse-specific relative to psychiatric controls, albeit at a more lenient level. Groups did not differ in SA.

CONCLUSIONS

Childhood abuse is associated with widespread structural abnormalities in OFC-insular, cerebellar, occipital, parietal and temporal regions, which likely underlie the abnormal affective, motivational and cognitive functions typically observed in this population.

Immunolocalization of myocilin protein in the anterior eye of normal and primary open-angle glaucomatous dogs

OBJECTIVE

The presence of myocilin was investigated in a colony of Beagles, a canine model for inherited primary open-angle glaucoma (POAG). The myocilin protein was localized in the normal and glaucomatous canine eyes by immunohistochemistry and immunocytochemistry.

METHODS

Paraffin- and plastic-embedded specimens from the anterior uveas of 10 Beagles with inherited glaucoma (3 months to 13 years old) and 6 age-matched normal dogs were sectioned, and were then incubated with primary antibody, rabbit polyclonal antihuman MYOC IgG, overnight at 4 degrees C. Specimens were incubated with secondary antibody with one of the following: biotinylated link followed by peroxidase-labeled streptavidin and then by substrate-chromogen for light microscopy; fluorescent marker Texas red; or 18 nm colloidal gold-labeled goat antirabbit IgG for transmission electron microscopy.

RESULTS

With normal, pre- and early glaucomatous canine specimens, cell membranes of smooth muscle cells of the iris and ciliary body stained positively, as well as most resident stromal and vascular endothelial cells. The cytoplasm of cells within the nonpigmented ciliary epithelium of the ciliary body processes stained intensely, being weaker along the pars plana. Trabecular meshwork (TM) cells and surrounding extracellular matrix labeled, as well as the sclera adjacent to the angular aqueous plexus. In specimens with moderate and advanced glaucoma, greater intensity of staining was observed within TM cells and adjacent sclera, and portions of the nonpigmented epithelium of the ciliary processes. Fibrinous material labeled intensely within the posterior chamber.

CONCLUSIONS

Myocilin in the normal and glaucomatous canine eye was successfully immunolocalized. These findings with regard to the normal eye are nearly identical to those previously reported in humans, and support the original hypothesis that there is an increase in both accumulation and localization of myocilin in glaucomatous canine eyes. It also supports the possibility that changes in the activity of myocilin within the aqueous humor outflow pathway of individuals with spontaneous glaucoma are associated with the rise of intraocular pressure and subsequent development of this disease, but may not be the primary event in the initial raise in intraocular pressure in POAG in the Beagle.

Contrast?Enhanced Cardiac Magnetic Resonance in a Patient with Familial Isolated Ventricular Non?compaction

Isolated ventricular non-compaction (IVNC) is an idiopathic form of cardiomyopathy. Recent clinical reports have suggested that this form of cardiomyopathy is more frequently associated with complications of congestive heart failure, thromboembolism and malignant ventricular arrhythmias. Contrast enhanced cardiac magnetic resonance imaging with its excellent spatial resolution, its large field of view and its ability to demonstrate thrombus and myocardial scar is an excellent modality to non-invasively assess patients with this form of cardiomyopathy. This paper presents a case of familial isolated ventricular non-compaction. We describe the echocardiographic, X-ray angiographic and cardiac MRI findings. Cine imaging using a steady-state free precession sequence (BFFE) was performed in axial and short axis planes. Left ventricular (LV) mass was estimated both with and without the incorporation of trabeculations from a contiguous stack of short axis images. Trabecular mass was expressed as a percentage of total left ventricular mass. We compared trabecular mass: total LV mass in 10 patients with dilated cardiomyopathy. The mean percentage trabecular mass: LV mass in dilated cardiomyopathy was 11.3% (range 1.5%-19%), and this differed significantly from the trabecular mass of the noncompaction patient (two-tailed Mann-Whitney test, p = 0.028). Trabecular mass of greater than 20% of total myocardial mass may be a useful index to suggest the diagnosis of IVNC. Gadolinium was administered (0.1 mmol/kg). Qualitative analysis of first pass perfusion suggested reduced trabecular perfusion. Early imaging with an inversion recovery sequence and a fixed long inversion time did not demonstrate LV thrombus. Late imaging with the same sequence (TI = 280-300 msec) did not demonstrate myocardial fibrosis.

Effects of a functional therapy program on motor abilities of children with cerebral palsy

BACKGROUND AND PURPOSE

The purpose of this study was to determine whether the motor abilities of children with spastic cerebral palsy who were receiving functional physical therapy (physical therapy with an emphasis on practicing functional activities) improved more than the motor abilities of children in a reference group whose physical therapy was based on the principle of normalization of the quality of movement.

SUBJECTS

The subjects were 55 children with mild or moderate cerebral palsy aged 2 to 7 years (median=55 months).

METHODS

A randomized block design was used to assign the children to the 2 groups. After a pretest, the physical therapists for the functional physical therapy group received training in the systematic application of functional physical therapy. There were 3 follow-up assessments: 6, 12, and 18 months after the pretest. Both basic gross motor abilities and motor abilities in daily situations were studied, using the Gross Motor Function Measure (GMFM) and the self-care and mobility domains of the Pediatric Evaluation of Disability Inventory (PEDI), respectively.

RESULTS

Both groups had improved GMFM and PEDI scores after treatment. No time x group interactions were found on the GMFM. For the PEDI, time x group interactions were found for the functional skills and caregiver assistance scales in both the self-care and mobility domains.

DISCUSSION AND CONCLUSION

The groups' improvements in basic gross motor abilities, as measured by the GMFM in a standardized environment, did not differ. When examining functional skills in daily situations, as measured by the PEDI, children in the functional physical therapy group improved more than children in the reference group.

Characterization of Gac1p, a regulatory subunit of protein phosphatase type I involved in glycogen accumulation in Saccharomyces cerevisiae

GAC1 and GLC7 encode regulatory and catalytic subunits, respectively, of a type 1 phosphatase (PP1) in Saccharomyces cerevisiae that controls glycogen synthesis by regulating the phosphorylation state of glycogen synthase (Gsy2p). To investigate the role of Gac1p in this process, a set of GAC1 deletions were tested for their ability to complement a gac1 null mutation and to associate with Glc7p and with Gsy2p. The N-terminal 93 amino acids of Gaclp are necessary and sufficient for the interaction with Glc7p, whereas a region spanning residues 130-502 is required for Gsy2p binding. Both domains are required for full activity in vivo, although the Glc7p-binding domain retains some residual activity and can alter the phosphorylase a phosphatase activity of Glc7p in vitro. Further mutational analysis showed that Val71 and Phe73 of Gaclp are necessary for binding to Glc7p, while Asn356 and Tyr357 of Gaclp are necessary for binding to Gsy2p. These results suggest that Gac1p targets PPI to its substrate Gsy2p and that Gac1p may alter the catalytic activity of PP . Our data also show that overexpression of Gac1p affects glucose repression and ion homeostasis, two additional targets of GLC7, suggesting that multiple regulatory subunits compete for Glc7p binding in vivo.

Comparison of the inactivation of canine and bovine parvovirus by freeze-drying and dry-heat treatment in two high purity factor VIII concentrates

The inactivation of bovine parvovirus (BPV) and canine parvovirus (CPV) by freeze-drying and terminal dry-heat treatment at 80 degrees C for 72 h has been investigated in two high purity factor VIII concentrates. In one product, CPV was slightly more resistant to freeze-drying compared to BPV, i.e. 0.7 vs. 1.4 log. However, BPV was substantially more resistant to heat-treatment compared to CPV, i.e. 1.3 vs. > 3.1 log inactivation after 72 h at 80 degrees C. In a second product, CPV was also slightly more resistant to freeze-drying than BPV, i.e. 0.2 vs. 1.3 log inactivation. However, heat-treatment gave essentially similar inactivation for both viruses, i.e. 2.8-3.4 log after 72 h at 80 degrees C. In conclusion, the resistance of these parvovirus models is dependent both on the type of virus and on the specific product involved.

Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease. PART-2 Collaborative Research Group. Prevention of Atherosclerosis with Ramipril

OBJECTIVES

The primary objective of this study was to investigate the effects of the angiotensin-converting enzyme (ACE) inhibitor, ramipril, on carotid atherosclerosis in patients with coronary, cerebrovascular or peripheral vascular disease.

BACKGROUND

Angiotensin-converting enzyme inhibitors have been shown to reduce the risk of coronary events in various patient groups and to prevent the development of atherosclerosis in animal models. It has been hypothesized that the clinical benefits of ACE inhibitors may, therefore, be mediated by effects on atherosclerosis.

METHODS

Six hundred seventeen patients were randomized in equal proportions to ramipril (5-10 mg daily) or placebo. At baseline, two years and four years, carotid atherosclerosis was assessed by B-mode ultrasound, and left ventricular mass was assessed by M-mode echocardiography.

RESULTS

Blood pressure (BP) was reduced by a mean of 6 mm Hg systolic and 4 mm Hg diastolic in the ramipril group compared with the placebo group (p<0.001). There was no difference between groups in the changes in common carotid artery wall thickness (p = 0.58) or in carotid plaque (p = 0.93). Left ventricular mass index decreased by 3.8 g/m2 (4%) in the ramipril group compared with the placebo group (2p = 0.04).

CONCLUSIONS

The results provide no support for the hypothesis that reduced atherosclerosis is responsible for the beneficial effects of ACE inhibitors on major coronary events. It is more likely that the benefits are due to lower BP, reduced left ventricular mass or other factors such as reversal of endothelial dysfunction.

Effects of lowering average of below-average cholesterol levels on the progression of carotid atherosclerosis: results of the LIPID Atherosclerosis Substudy. LIPID Trial Research Group

BACKGROUND

Cholesterol lowering in patients with above-average cholesterol levels has been shown to reduce the progression of atherosclerosis and lower the risk of coronary heart disease events. However, there has been uncertainty about the effects of cholesterol lowering in patients with average or below-average cholesterol levels.

METHODS AND RESULTS

In this study, 522 patients with a history of myocardial infarction or unstable angina and with baseline levels of total cholesterol between 4 and 7 mmol/L (mean, 5.7 mmol/L) were randomized to treatment with a low fat diet plus pravastatin (40 mg daily) or to a low fat diet plus placebo. Treatment with pravastatin reduced the levels of total cholesterol by 19%, LDL cholesterol by 27%, apolipoprotein B by 19%, and triglycerides by 13% (all 2P<.0001) and increased apolipoprotein A1 and HDL cholesterol levels by 4% (both 2P<.0005), in comparison with placebo. Carotid atherosclerosis was assessed from B-mode ultrasound measurements of the common carotid artery. After 4 years, mean carotid wall thickness had increased by 0.048 mm (SE=0.01) in the placebo group and declined by 0.014 mm in the pravastatin-treated group (SE=0.01) (2P for difference <.0001). The effect of treatment on wall thickness was similar in three groups classified by tertiles of total cholesterol at baseline, with mean levels of 4.8, 5.7, and 6.6 mmol/L, respectively (2P for interaction >.8).

CONCLUSIONS

Treatment with pravastatin reduced the development of carotid atherosclerosis among patients with coronary heart disease and a wide range of pretreatment cholesterol levels. Treatment with this agent prevented any detectable increase in carotid wall thickening over 4 years of follow-up.

Long-term effects of continuous combined HRT on bone turnover and lipid metabolism in postmenopausal women

This study was undertaken to investigate the effect of 10 years of hormone replacement therapy (HRT) on bone turnover and lipid metabolism in postmenopausal women. The single-centre trial was initiated as a 1-year, double-masked, randomized, parallel-group study of continuous combined HRT with 2 mg 17 beta-estradiol and 1 mg norethisterone acetate administered once daily with or without 1 mg estriol. Following preliminary results which showed no difference between the addition and omission of estriol, patients continued on an open-label extension phase of continuous combined HRT without estriol for a further 9 years. Of the 52 women who entered the original double-masked study, 32 entered the open-label extension phase. The 10-year analysis was based on 27 patients. Major increases in bone mineral density (BMD) of the lumbar spine were seen during the first 3 years of treatment, remaining statistically significant compared with baseline at all visits throughout the 10-year follow-up (p < or = 0.025). Statistical modelling confirmed that there were no decreases in BMD after these initial increases. BMD remained 5.5% higher than baseline values after 10 years of continuous combined HRT. Mean total cholesterol levels were significantly reduced after 10 years of therapy (p = 0.012), with no significant changes in serum triglyceride and low-density lipoprotein (LDL)-cholesterol levels from baseline values at this time. High-density lipoprotein (HDL)-cholesterol levels, however, were reduced by 15.4% (p < 0.001). In conclusion, 10 years of continuous combined HRT resulted in a significant and sustained increase in BMD. This treatment regimen therefore appears to be well suited for the long-term prevention of osteoporosis in postmenopausal women.

Phylogenetic relationships in the Crassulaceae inferred from chloroplast DNA restriction-site variation

A restriction-site analysis of chloroplast DNA from 44 species, representing 19 genera and all six subfamilies of the Crassulaceae was conducted using 12 restriction endonucleases. A total of 969 variable sites was detected, 608 of which were phylogenetically informative and used in parsimony analysis. Estimated values of nucleotide sequence divergence were used to construct a distance tree by the neighbor-joining method. Maximum sequence divergence in the family was ~7%. Different tree inference methods yielded only moderately different topologies. The amount of support for the monophyletic groups obtained in the Wagner parsimony analysis was evaluated by bootstrap and decay analysis. There is very strong support for a basal division of the family, which separates the monophyletic subfamily Crassuloideae from all other taxa. Four of the six traditionally recognized subfamilies are indicated to be polyphyletic. These include the Cotyledonoideae, Sempervivoideae, Sedoideae, and Echeverioideae. The Kalanchoideae and the genera Cotyledon and Adromischus exhibit low levels of cpDNA sequence divergence relative to one another, suggesting a relatively recent radiation. The genera Sedum and Rosularia are indicated to be polyphyletic. Sedum comprises sister taxa of most of the other genera of the family.

Management of acute myocardial infarction in Auckland

AIM

To analyse the utilisation of therapies in coronary care units for patients with acute myocardial infarction.

METHODS

An evaluation form was completed prospectively by a designated nurse in each coronary care unit of the four Auckland hospitals in 1993.

RESULTS

One thousand and eighty one patients who were admitted with definite or probable acute myocardial infarction had a coronary care unit stay of 63.4 (SD 49.3) hours, and hospital stay of 7.3 (5.1) days. The mortality for definite myocardial infarction was 13.7% (< 70 years 7.1%). Coronary angiography was performed on 10% of patients during their hospital admission, and 4.9% underwent revascularisation. Thrombolytic therapy was administered to 52% (495/948) of patients with definite infarction and 4% had contraindications. Patients aged > or = 70 years (47% vs 55% p = 0.02) or diabetics (46% vs 56%, p = 0.04) were less likely to receive thrombolysis. The utilisation of aspirin and oral beta-blockers was 86% and 40%, respectively, in patients with definite infarction and both were used less frequently in patients > or = 70 years. Intravenous beta-blockers were administered to < 1% of patients. Angiotensin converting enzyme (ACE) inhibitors were prescribed in 21%, intravenous or long acting nitrates in 41% and calcium antagonists in 14%; the latter two therapies were used more frequently in patients > or = 70 years. There was no evidence of gender or ethnic bias for either investigation or treatment.

CONCLUSION

On the basis of results of recent clinical trials, there may be under utilisation of some treatments for acute myocardial infarction including aspirin, thrombolytic therapy, beta-blockers and ACE inhibitors, while calcium antagonists may be over used.

In vivo assessment of the atrophogenic potency of mometasone furoate, a newly developed chlorinated potent topical glucocorticoid as compared to other topical glucocorticoids old and new

Topical glucocorticoids still belong to the most important medications available in dermatotherapy. The clinical use of topical glucocorticoids, however, nowadays is limited by the fear of side-effects both systemic and local, especially skin atrophy. The purpose of this study was to assess the atrophogenicity potential of newly developed topical glucocorticoids which were said to show an increased benefit-risk ratio. The test preparations comprised mometasone furoate, the corresponding vehicle, prednicarbate and hydrocortisone. They were applied once or twice daily for 6 weeks in healthy volunteers. Skin thickness was assessed weekly by using high frequency pulsed ultrasound. Clinically, none of the volunteers showed any sign of overt skin atrophy. Skin thickness, however, was reduced to a certain extent with all trial preparations including the base preparation. As to be expected from previous experiments the results for hydrocortisone and prednicarbate did not differ significantly from the ones for the base preparation. Interestingly, the same applied to mometasone furoate. These findings, together with the other available data, give evidence of an increased benefit-risk ratio as compared to previous medium potent topical glucocorticoids. This might be of particular interest facing psoriasis vulgaris where an antiproliferative activity of a drug is needed.

Absence of hepatitis A virus transmission by high-purity solvent detergent treated coagulation factor concentrates in Scottish haemophiliacs

Recent reports of hepatitis A virus (HAV) infection in haemophiliacs receiving high-purity solvent detergent (HP.SD) treated factor VIII concentrates have brought into question the efficacy of this virucidal method for inactivating HAV. To assess whether HAV may have been transmitted by HP.SD concentrates, we compared seroprevalence in haemophiliacs with different disease severity, sought evidence of seroconversion to HAV since introduction of HP.SD products, and directly examined concentrates for HAV RNA by PCR. Our data suggest that Scottish haemophiliacs are not being infected with HAV by HP.SD concentrates produced initially by CRTS Lille and presently by PFC Edinburgh and supplied by the Scottish National Blood Transfusion Service (SNBTS).

Comparison of tests for the lupus anticoagulant and antiphospholipid antibodies in systemic lupus erythematosus

A variety of laboratory assays are used to screen for the presence of the lupus anticoagulant. Six commonly used coagulation tests, and the ELISA assay for antiphospholipid antibody using three different substrate phospholipids, have been evaluated in 110 patients with systemic lupus erythematosus or lupus-like disease. One or more coagulation assays was abnormal in 41% (45/110) of the patients. No individual test detected more than 78% of these abnormalities, indicating that a single phospholipid based coagulation test cannot be used to screen for a possible lupus anticoagulant. A combination of Actin FSL, DTTA and DRVVT detected all the abnormalities. The most sensitive two-test combination was Actin FSL and DRVVT. Approximately half (56%) of the patients with a positive clotting test had an abnormal antiphospholipid antibody assay. A similar proportion (58%) of the aPL positive patients had a prolonged coagulation test. The marked discordance between the coagulation assays and a positive antiphospholipid antibody test further complicates the laboratory definition of this abnormality, at least in patients with systemic lupus erythematosus.

Molecular evolution of noncoding regions of the chloroplast genome in the Crassulaceae and related species

Universal primers were used for PCR amplification of three noncoding regions of chloroplast DNA (cpDNA) in order to study sequence-length variation in the Crassulaceae and in related species. Several length mutations were observed that are of diagnostic value for evolutionary relationships in the Crassulaceae and the Saxifragaceae. Length variation and sequence divergence in the intergenic spacer between the trnL (UAA) 3' exon and the trnF (GAA) gene among 15 species were studied in detail by nucleotide-sequence analysis. A total of 50 insertion/deletion mutations were observed, accounting for a spacer-length variation in the range of 228-360 bp. Eighteen short direct repeat motifs (4-11 bp) and two inverted repeat motifs (7-11 bp) were found to be associated with length variation. Phylogenetic analysis of the sequence data indicated a pattern of relationships that was largely consistent with a previous analysis of cpDNA restriction-site variation. Evaluation of the level of homoplasy in insertion/deletion mutations within a phylogenetic framework revealed that only 1 out of 34 length mutations longer than 2 bp must have had multiple origins. The feasibility of the noncoding chloroplast DNA regions for molecular evolutionary studies is discussed.

Effect of monosaccharides during severe dry heat treatment of coagulation factor VIII concentrates

During product development of a factor VIII concentrate (Dutch blood banks) the conversion from unsterilized to autoclaved freeze-drying buffer caused impaired product characteristics after severe dry heat treatment (80 degrees C for 72 h). Analysis of the freeze-drying buffers showed the presence of fructose and glucose in heated buffers, resulting from hydrolysis of sucrose. The detrimental effect of glucose and fructose on solubility, yield of factor VIII and color of the heat-treated product was confirmed by freeze-drying and heating products spiked with increasing levels of these monosaccharides. The effect of the use of freeze-drying buffers autoclaved with and without sucrose was examined in two other factors VIII concentrates, S(8) and Z8 (Protein Fractionation Centre, Edinburgh, UK). If sucrose was present during autoclaving of the buffer, a slightly lower yield over freeze-drying and 80 degrees C heat treatment was observed. Since glucose is present as a substrate in the medium for the host cells during cultivation of viruses, its potential effect on the 80 degrees C heated product (Dutch blood banks) was examined during the validation study of the inactivation of HIV-1 and Sindbis. The cultivation cycles for the virus inocula were simulated and residual glucose levels measured. In the supernatant medium of the host cell culture used for the propagation of Sindbis no residual glucose was found. Glucose however was found in the supernatant medium of the host cell culture for propagation of HIV-1, and therefore small molecular weight substances were removed from the actual HIV-1 inoculum by ultrafiltration.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of polymerase chain reaction and an infectivity assay for human immunodeficiency virus type 1 titration during virus inactivation of blood components

Three examples of human plasma-derived concentrates, intermediate-purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV-1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus-inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.