Decoding cerebro-spinal signatures of human behavior: application to motor sequence learning

Mapping the neural patterns that drive human behavior is a key challenge in neuroscience. Even the simplest of our everyday actions stem from the dynamic and complex interplay of multiple neural structures across the central nervous system (CNS). Yet, most neuroimaging research has focused on investigating cerebral mechanisms, while the way the spinal cord accompanies the brain in shaping human behavior has been largely overlooked. Although the recent advent of functional magnetic resonance imaging (fMRI) sequences that can simultaneously target the brain and spinal cord has opened up new avenues for studying these mechanisms at multiple levels of the CNS, research to date has been limited to inferential univariate techniques that cannot fully unveil the intricacies of the underlying neural states. To address this, we propose to go beyond traditional analyses and instead use a data-driven multivariate approach leveraging the dynamic content of cerebro-spinal signals using innovation-driven coactivation patterns (iCAPs). We demonstrate the relevance of this approach in a simultaneous brain-spinal cord fMRI dataset acquired during motor sequence learning (MSL), to highlight how large-scale CNS plasticity underpins rapid improvements in early skill acquisition and slower consolidation after extended practice. Specifically, we uncovered cortical, subcortical and spinal functional networks, which were used to decode the different stages of learning with a high accuracy and, thus, delineate meaningful cerebro-spinal signatures of learning progression. Our results provide compelling evidence that the dynamics of neural signals, paired with a data-driven approach, can be used to disentangle the modular organization of the CNS. While we outline the potential of this framework to probe the neural correlates of motor learning, its versatility makes it broadly applicable to explore the functioning of cerebro-spinal networks in other experimental or pathological conditions.

Epidemiology and outcomes of hospital-acquired bloodstream infections in intensive care unit patients: the EUROBACT-2 international cohort study

PURPOSE

In the critically ill, hospital-acquired bloodstream infections (HA-BSI) are associated with significant mortality. Granular data are required for optimizing management, and developing guidelines and clinical trials.

METHODS

We carried out a prospective international cohort study of adult patients (≥ 18 years of age) with HA-BSI treated in intensive care units (ICUs) between June 2019 and February 2021.

RESULTS

2600 patients from 333 ICUs in 52 countries were included. 78% HA-BSI were ICU-acquired. Median Sequential Organ Failure Assessment (SOFA) score was 8 [IQR 5; 11] at HA-BSI diagnosis. Most frequent sources of infection included pneumonia (26.7%) and intravascular catheters (26.4%). Most frequent pathogens were Gram-negative bacteria (59.0%), predominantly Klebsiella spp. (27.9%), Acinetobacter spp. (20.3%), Escherichia coli (15.8%), and Pseudomonas spp. (14.3%). Carbapenem resistance was present in 37.8%, 84.6%, 7.4%, and 33.2%, respectively. Difficult-to-treat resistance (DTR) was present in 23.5% and pan-drug resistance in 1.5%. Antimicrobial therapy was deemed adequate within 24 h for 51.5%. Antimicrobial resistance was associated with longer delays to adequate antimicrobial therapy. Source control was needed in 52.5% but not achieved in 18.2%. Mortality was 37.1%, and only 16.1% had been discharged alive from hospital by day-28.

CONCLUSIONS

HA-BSI was frequently caused by Gram-negative, carbapenem-resistant and DTR pathogens. Antimicrobial resistance led to delays in adequate antimicrobial therapy. Mortality was high, and at day-28 only a minority of the patients were discharged alive from the hospital. Prevention of antimicrobial resistance and focusing on adequate antimicrobial therapy and source control are important to optimize patient management and outcomes.

Lung Ultrasound-Guided Fluid Management versus Standard Care in Surgical ICU Patients: A Randomised Controlled Trial

The value of lung ultrasound (LU) in assessing extravascular lung water (EVLW) was demonstrated by comparing LU with gold-standard methods for EVLW assessment. However, few studies have analysed the value of B-Line score (BLS) in guiding fluid management during critical illness. The purpose of this trial was to evaluate if a BLS-guided fluid management strategy could improve fluid balance and short-term mortality in surgical intensive care unit (ICU) patients. We conducted a randomised, controlled trial within the ICUs of two university hospitals. Critically ill patients were randomised upon ICU admission in a 1:1 ratio to BLS-guided fluid management (active group) or standard care (control group). In the active group, BLS was monitored daily until ICU discharge or day 28 (whichever came first). On the basis of BLS, different targets for daily fluid balance were set with the aim of avoiding or correcting moderate/severe EVLW increase. The primary outcome was 28-day mortality. Over 24 months, 166 ICU patients were enrolled in the trial and included in the final analysis. Trial results showed that daily BLS monitoring did not lead to a different cumulative fluid balance in surgical ICU patients as compared to standard care. Consecutively, no difference in 28-day mortality between groups was found (10.5% vs. 15.6%, p = 0.34). However, at least 400 patients would have been necessary for conclusive results.

Influence of aerobic exercise training on the neural correlates of motor learning in Parkinson's disease individuals

Background

Aerobic exercise training (AET) has been shown to provide general health benefits, and to improve motor behaviours in particular, in individuals with Parkinson's disease (PD). However, the influence of AET on their motor learning capacities, as well as the change in neural substrates mediating this effect remains to be explored.

Objective

In the current study, we employed functional Magnetic Resonance Imaging (fMRI) to assess the effect of a 3-month AET program on the neural correlates of implicit motor sequence learning (MSL).

Methods

20 healthy controls (HC) and 19 early PD individuals participated in a supervised, high-intensity, stationary recumbent bike training program (3 times/week for 12 weeks). Exercise prescription started at 20 min (+ 5 min/week up to 40 min) based on participant's maximal aerobic power. Before and after the AET program, participants' brain was scanned while performing an implicit version of the serial reaction time task.

Results

Brain data revealed pre-post MSL-related increases in functional activity in the hippocampus, striatum and cerebellum in PD patients, as well as in the striatum in HC individuals. Importantly, the functional brain changes in PD individuals correlated with changes in aerobic fitness: a positive relationship was found with increased activity in the hippocampus and striatum, while a negative relationship was observed with the cerebellar activity.

Conclusion

Our results reveal, for the first time, that exercise training produces functional changes in known motor learning related brain structures that are consistent with improved behavioural performance observed in PD patients. As such, AET can be a valuable non-pharmacological intervention to promote, not only physical fitness in early PD, but also better motor learning capacity useful in day-to-day activities through increased plasticity in motor related structures.

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Three months of aerobic exercise training (AET) improves fitness in PD patients.

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Effects of AET on cognitive and motor skills in PD were evaluated concurrently.

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Some executive functions and procedural learning capacity improved after AET.

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Striatum, hippocampus and cerebellar brain plasticity was observed after AET.

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AET can be used as a non-pharmacological intervention to improve functioning in PD.

Schizophrénie et violence : rôle de l’impulsivité, étude en imagerie fonctionnelle

De nombreuses études ont montré qu’il y a une association entre les comportements violents et le fait d’avoir un diagnostic de schizophrénie (Sz) [1,2]. Cependant, il a aussi été démontré que seulement une minorité des patients sera violente . Plusieurs études ont considéré ces phénomènes afin de mieux identifier les personnes à risque et, par la suite, des échelles d’évaluation où l’on retrouve des facteurs de risque psychosociaux ont été développées. Bien qu’intéressantes, ces échelles demeurent imparfaites pour déterminer le risque . Face à cette situation, la neurobiologie du risque a commencé à se développer, mais encore peu d’études ont examiné les corrélats neuronaux de la violence dans cette population, et particulièrement, en ce qui concerne les facteurs liés à l’expérience émotionnelle et au contrôle pulsionnel. Notre équipe a donc réalisé deux études d’imagerie par résonance magnétique fonctionnelle (IRMf) chez cette population. Les résultats de ces 2 études seront présentés. Brièvement, le projet portant sur l’expérience des émotions négatives a montré une hyperactivation du cortex cingulaire antérieur dorsal chez les patients Sz violents (SzV), comparativement aux patients Sz non violents (SzNV) et aux témoins sains (TS). Il s’agit d’un résultat intéressant puisque cette zone est impliquée dans la régulation émotionnelle. Les résultats préliminaires de la deuxième étude montrent, en utilisant une tâche de prise de risque, que les patients SzV ont des activations importantes dans le système de récompense du cerveau lors de la réception d’une récompense en argent (x = −24 ; y = −13 ; z = 13 ; p < 0,001 ; 3080 mm3), comparativement aux patients SzNV et aux TS. Les résultats de nos deux premières études montrent ainsi qu’une spécificité neurobiologique existe chez les patients violents en ce qui a trait à la régulation émotionnelle et à l’activation du système de récompense.

Varicella zoster virus in human and rat tissue specimens

The limited supple of appropriate tissues for study has been an impediment to investigations of varicella zoster virus (VZV) latency. Human dorsal root ganglia (DRG) harboring latent virus are not plentiful and are not amenable to manipulation for studying the events surrounding the establishment, maintenance, and cessation of latency. An alternative to studies in human DRG is the rat model of latency, which appears to provide a reliable method of investigating VZV latency. Other alternatives include studies in other human tissues involved in VZV pathogenesis. In order to improve our understanding of the establishment and cessation of latency, we performed comparative immunohistochemical analysis of chickenpox and zoster skin lesions. This analysis revealed that during primary infection and reactivation productive VZV infection occurs in a variety of cell types and that the major VZV DNA binding protein, ORF29p, is present in peripheral axons early during the course of chickenpox. VZV latency was studied in the rat model by in situ hybridization and compared with similar studies performed in human DRG containing latent virus, confirming that VZV DNA persists in the same sites in DRG of the two species.

Essential role played by the C-terminal domain of glycoprotein I in envelopment of varicella-zoster virus in the trans-Golgi network: interactions of glycoproteins with tegument

Varicella-zoster virus (VZV) is enveloped in the trans-Golgi network (TGN). Here we report that glycoprotein I (gI) is required within the TGN for VZV envelopment. Enveloping membranous TGN cisternae were microscopically identified in cells infected with intact VZV. These sacs curved around, and ultimately enclosed, nucleocapsids. Tegument coated the concave face of these sacs, which formed the viral envelope, but the convex surface was tegument-free. TGN cisternae of cells infected with VZV mutants lacking gI (gI(Delta)) or its C (gI(DeltaC))- or N-terminal (gI(DeltaN))-terminal domains were uniformly tegument coated and adhered to one another, forming bizarre membranous stacks. Viral envelopment was compromised, and no virions were delivered to post-Golgi structures. The TGN was not gI-immunoreactive in cells infected with the gI(Delta) or gI(DeltaN) mutants, but it was in cells infected with gI(DeltaC) (because the ectodomains of gI and gE interact). The presence in the TGN of gI lacking a C-terminal domain, therefore, was not sufficient to maintain enveloping cisternae. In cells infected with intact VZV or with gI(Delta), gI(DeltaN), or gI(DeltaC) mutants, ORF10p immunoreactivity was concentrated on the cytosolic face of TGN membranes, suggesting that it interacts with the cytosolic domains of glycoproteins. Because of the gE-gI interaction, cotransfected cells that expressed gE or gI were able to target truncated forms of the other to the TGN. Our data suggest that the C-terminal domain of gI is required to segregate viral and cellular proteins in enveloping TGN cisternae.

Open reading frame S/L of varicella-zoster virus encodes a cytoplasmic protein expressed in infected cells

We report the discovery of a novel gene in the varicella-zoster virus (VZV) genome, designated open reading frame (ORF) S/L. This gene, located at the left end of the prototype VZV genome isomer, expresses a polyadenylated mRNA containing a splice within the 3' untranslated region in virus-infected cells. Sequence analysis reveals significant differences between the ORF S/Ls of wild-type and attenuated strains of VZV. Antisera raised to a bacterially expressed portion of ORF S/L reacted specifically with a 21-kDa protein synthesized in cells infected with a VZV clinical isolate and with the original vaccine strain of VZV (Oka-ATCC). Cells infected with other VZV strains, including a wild-type strain that has been extensively passaged in tissue culture and commercially produced vaccine strains of Oka, synthesize a family of proteins ranging in size from 21 to 30 kDa that react with the anti-ORF S/L antiserum. MeWO cells infected with recombinant VZV harboring mutations in the C-terminal region of the ORF S/L gene lost adherence to the stratum and adjacent cells, resulting in an altered plaque morphology. Immunohistochemical analysis of VZV-infected cells demonstrated that ORF S/L protein localizes to the cytoplasm. ORF S/L protein was present in skin lesions of individuals with primary or reactivated infection and in the neurons of a dorsal root ganglion during virus reactivation.

Trafficking of varicella-zoster virus glycoprotein gI: T(338)-dependent retention in the trans-Golgi network, secretion, and mannose 6-phosphate-inhibitable uptake of the ectodomain

The trans-Golgi network (TGN) is putatively the site where varicella-zoster virus is enveloped. gE is targeted to the TGN by selective retrieval from the plasmalemma in response to signaling sequences in its endodomain. gI lacks these sequences but forms a complex with gE. We now find that gI is targeted to the TGN and plasma membrane when expressed in Cos-7 cells; nevertheless, surface labeling revealed that gI is not retrieved from the plasma membrane. TGN targeting of gI depended on the T(338) of its endodomain and was lost when T(338) was deleted or mutated to A, S, or D. The endodomain of gI was sufficient, if it contained T(338), to target a fusion protein containing the ectodomain of the human interleukin-2 receptor to the TGN. A truncated protein consisting only of the gI ectodomain was secreted and taken up by nontransfected cells. This uptake of the secreted gI ectodomain was blocked by mannose 6-phosphate. Following cotransfection, both gI and gE were retrieved to the TGN from the plasma membrane in 26.7% of cells, neither gI nor gE was internalized in 18.3%, and gE was retrieved to the TGN while gI remained at the plasma membrane in 55%. We suggest that the T(338) of its endodomain is necessary to retain gI in the TGN; moreover, because gI and gE interact, the signaling sequences of each glycoprotein reinforce one another in ensuring that both glycoproteins are concentrated in the TGN yet remain on the cell surface.

Varicella-zoster virus proteins in skin lesions: implications for a novel role of ORF29p in chickenpox

Skin biopsy samples from varicella-zoster virus (VZV)-infected patients examined by immunohistochemistry demonstrated VZV replication in nonepithelial cell types. ORF29p, a nonstructural nuclear protein, was found in nerves of two of six patients with chickenpox. In tissue culture, ORF29p was secreted by VZV-infected fibroblasts. Extracellular ORF29p can be taken up through endocytosis by human neurons, implying a novel role for this protein in pathogenesis.

Evidence of latent varicella-zoster virus in rat dorsal root ganglia

Latent varicella-zoster virus (VZV) was studied in ganglia of rats that had been inoculated subcutaneously with either a high-passaged wild-type, a low-passaged wild-type, or the vaccine strain of virus using in situ hybridization. Nine of 11 rats injected with virus and no control rats developed serum VZV antibodies as demonstrated by fluorescent antibody membrane antigen. Polymerase chain reaction 2 weeks following inoculation did not detect viremia in the rats. VZV was detected by in situ hybridization in ganglia of 10 of the 11 infected rats but not in ganglia of the control rats. The distribution of VZV DNA is identical to that seen in humans; satellite cells and neurons contain VZV DNA. Although all animals received unilateral injections of virus, VZV DNA was in ipsilateral and contralateral ganglia in 6 animals, suggesting that virus replication and viremia had occurred.

Intracellular transport of varicella-zoster glycoproteins

Previous observations have established that varicella-zoster virus (VZV) is enveloped in the trans-Golgi network (TGN) in cultures infected with VZV and that the glycoprotein gE is targeted to the TGN by a signal sequence (AYRV) and an acidic TGN signal patch in its cytosolic domain. Neither sequence is present in other VZV glycoproteins. Like gE, gI was targeted to the TGN when it was expressed in transfected cells, suggesting that gI also contains TGN targeting information (colocalized with gE and the AP-1 adaptin complex). In contrast, gB, gC, gH, and gL immunoreactivities were not detected in the TGN when they were expressed individually in transfected cells. In VZV-infected cells, gE, gI, gH, and gL were all concentrated in the TGN. Since VZV glycoproteins that lack targeting sequences (gB, gC, gH, and gL) concentrated in the TGN of infected cells, it is proposed that gE and gI, which have such sequences, serve as navigator glycoproteins, forming complexes that direct the signal-deficient glycoproteins to the TGN.

Congenital varicella-zoster virus infection and Barrett's esophagus

Congenital varicella syndrome is a rare complication of varicella-zoster virus (VZV) infection during pregnancy. An infant was exposed to VZV at 18.5 weeks of gestation and had eye and skin abnormalities at birth and persistent feeding difficulties, prompting esophageal biopsies at 12 days and 20 and 20.5 months of age. Esophageal tissues demonstrated specialized intestinal metaplasia (Barrett's esophagus). VZV DNA (in situ hybridization) and proteins (immunohistochemistry and polymerase chain reaction) were found in esophageal epithelial cells adjacent to the Barrett's lesion. Immediate-early 63 protein (IE63) of VZV was demonstrated in the day 12 specimen, and IE62 and the late VZV glycoprotein E (gE) were found in the 20-month specimen. Clinical and endoscopic improvement followed fundoplication and acyclovir therapy, but VZV DNA and IE62 persisted in esophageal tissue. These findings associate VZV with specialized intestinal metaplasia within the esophagus and suggest a novel site for either latent or active VZV infection.

Aberrant intracellular localization of Varicella-Zoster virus regulatory proteins during latency

Varicella-Zoster virus (VZV) is a herpesvirus that becomes latent in sensory neurons after primary infection (chickenpox) and subsequently may reactivate to cause zoster. The mechanism by which this virus maintains latency, and the factors involved, are poorly understood. Here we demonstrate, by immunohistochemical analysis of ganglia obtained at autopsy from seropositive patients without clinical symptoms of VZV infection that viral regulatory proteins are present in latently infected neurons. These proteins, which localize to the nucleus of cells during lytic infection, predominantly are detected in the cytoplasm of latently infected neurons. The restriction of regulatory proteins from the nucleus of latently infected neurons might interrupt the cascade of virus gene expression that leads to a productive infection. Our findings raise the possibility that VZV has developed a novel mechanism for maintenance of latency that contrasts with the transcriptional repression that is associated with latency of herpes simplex virus, the prototypic alpha herpesvirus.

In situ hybridization detection of varicella zoster virus in paraffin-embedded skin biopsy samples

BACKGROUND

When virologic and molecular diagnostic techniques are unavailable, the diagnosis of varicella zoster virus (VZV) infection depends on clinical criteria and histologic evaluation of skin biopsy specimens or Tzank preparations. These methods can misdiagnose chickenpox and zoster, particularly when the clinical manifestations are atypical.

OBJECTIVE

To improve diagnosis in these settings, we developed an in situ hybridization technique for the detection of VZV utilizing a fluorescein-labeled oligonucleotide probe visualized with anti-fluorescein alkaline phosphatase-conjugated antibody.

STUDY DESIGN

We retrospectively examined 26 paraffin-embedded skin biopsy specimens with histologic features consistent with VZV or herpes simplex virus (HSV) infection and 11 control cases by in situ hybridization. In situ hybridization for VZV and HSV-1 was compared with polymerase chain reaction (PCR) for VZV and HSV-1 and clinical and histologic examination.

RESULTS

Thirteen of the 26 study cases and two of the 11 control cases were positive for VZV by in situ hybridization. When compared with PCR, in situ hybridization was 92% sensitive and 88% specific. When compared with clinical diagnosis, in situ hybridization was 86% sensitive and 87% specific. All cases of chickenpox had VZV-positive inflammatory cells in the dermis but this finding was less frequent among the cases of zoster.

CONCLUSIONS

This in situ hybridization technique is a sensitive and specific method for the diagnosis of VZV in skin lesions that is applicable to most histopathology laboratory settings. In addition, in situ hybridization reveals individual infected cells and may provide insight into the pathogenesis of VZV skin infection.

Primary characterization of a herpesvirus agent associated with Kaposi's sarcomae

Detection of novel DNA sequences in Kaposi's sarcoma (KS) and AIDS-related body cavity-based, non-Hodgkin's lymphomas suggests that these neoplasms are caused by a previously unidentified human herpesvirus. We have characterized this agent using a continuously infected B-lymphocyte cell line derived from an AIDS-related lymphoma and a genomic library made from a KS lesion. In this cell line, the agent has a large episomal genome with an electrophoretic mobility similar to that of 270-kb linear DNA markers during clamped homogeneous electric field gel electrophoresis. A 20.7-kb region of the genome has been completely sequenced, and within this region, 17 partial and complete open reading frames are present; all except one have sequence and positional homology to known gammaherpesvirus genes, including the major capsid protein and thymidine kinase genes. Phylogenetic analyses using both single genes and combined gene sets demonstrated that the agent is a gamma-2 herpesvirus (genus Rhadinovirus) and is the first member of this genus known to infect humans. Evidence for transient viral transmission from infected to uninfected cells is presented, but replication-competent virions have not been identified in infected cell lines. Sera from patients with KS have specific antibodies directed against antigens of infected cell lines, and these antibodies are generally absent in sera from patients with AIDS without KS. These studies define the agent as a new human herpesvirus provisionally assigned the descriptive name KS-associated herpesvirus; its formal designation is likely to be human herpesvirus 8.

Reactivated and latent varicella-zoster virus in human dorsal root ganglia

Ganglia obtained at autopsy were examined by in situ hybridization from one patient with zoster (also called herpes zoster or shingles), two varicella-zoster virus (VZV)-seropositive patients with clinical evidence of zoster, one VZV-seronegative child, and one fetus. Ganglia positive for VZV had a hybridization signal in both neuronal and nonneuronal satellite cells. Ganglia obtained from the fetus and from the seronegative infant were consistently negative for VZV. Two striking observations were evident regarding the presence of VZV DNA in ganglia obtained from the individual with zoster at the time of death. First, ganglia innervating the sites of reactivation and ganglia innervating adjacent sites yielded strongly positive signals in neurons and satellite cells, whereas ganglia from distant sites were rarely positive. Second, VZV DNA was found in both the nuclei and the cytoplasm of neurons innervating areas of zoster. However, in neurons innervating zoster-free areas, VZV DNA was found only in the nucleus of neurons and their supporting satellite cells. Immunohistochemistry with a fluorescent monoclonal antibody to the VZV glycoprotein gpI, a late virus protein, revealed a positive signal in the cytoplasm of ganglia with clinical evidence of reactivation. These results illustrate that both neuronal and satellite cells become latently infected following primary VZV infection. The presence of VZV DNA and gpI in the cytoplasm of neurons demonstrates productive infection following reactivation at the site of latency.

Evaluation of the Hybrid Capture human papillomavirus deoxyribonucleic acid detection test

OBJECTIVE

Our purpose was to evaluate the sensitivity and accuracy of a new, nonradioactive human papillomavirus deoxyribonucleic acid detection method.

STUDY DESIGN

Cervical samples from 520 women were assayed for human papillomavirus deoxyribonucleic acid with both the Hybrid Capture test and polymerase chain reaction.

RESULTS

Human papillomavirus deoxyribonucleic acid was detected with Hybrid Capture in 106 (42%) of 254 samples from women with no evidence of cervical intraepithelial neoplasia and 211 (79%) of 266 with cervical intraepithelial lesions or cervical cancer. There was a good correlation between Hybrid Capture and polymerase chain reaction. Hybrid Capture correctly identified 92% of samples found to contain a human papillomavirus type with a high or intermediate oncogenic risk with polymerase chain reaction. Although Hybrid Capture can quantify the amount of human papillomavirus deoxyribonucleic acid present in a sample, no correlation was observed between the relative amount of human papillomavirus deoxyribonucleic acid detected with Hybrid Capture and the grade of cervical lesion.

CONCLUSION

The Hybrid Capture test is a sensitive and accurate method for identifying human papillomavirus types of high and intermediate oncogenic risk in clinical specimens.

Human papillomavirus infection in human immunodeficiency virus-seropositive women

OBJECTIVE

To compare the prevalence of human papillomavirus (HPV) infections in women who are seropositive and seronegative for human immunodeficiency virus (HIV), and to determine if associations between HPV and cervical disease are altered in HIV-seropositive women.

METHODS

In this cross-sectional study, 344 HIV-seropositive and 325 HIV-seronegative women underwent colposcopy and HPV DNA testing.

RESULTS

Human immunodeficiency virus-seropositive women were more likely than HIV-seronegative women to have HPV DNA of any type detected (60 versus 36%, P < .001). Infections with HPV type 16 (27 versus 17%, P < .05), type 18 (24 versus 9%, P < .05), and more than one type of HPV (51 versus 26%, P < .05) were also more common in HIV-positive women. Although both latent HPV infection and HPV infections associated with cervical intraepithelial neoplasia (CIN) were more prevalent in the HIV-seropositive group, the ratio between these two types of infections was altered markedly in the HIV-seropositive women. Human immunodeficiency virus-seropositive women who were HPV-infected were significantly more likely to have CIN than were HPV-infected HIV-seronegative women, an increase observed at all levels of immunosuppression. Analysis of specific HPV types associated with latent HPV infection and CIN indicated that HIV seropositivity only minimally alters the known associations between specific types of HPV and cervical disease.

CONCLUSION

Human papillomavirus infections are more common among HIV-seropositive women at all levels of immunosuppression. However, relationships between HIV and HPV are complex and cannot be explained completely by an increased susceptibility to new HPV infections in the immunosuppressed patient.

A polymerase chain reaction-enzyme-linked immunosorbent assay method for detecting human papillomavirus in cervical carcinomas and high-grade cervical cancer precursors

OBJECTIVE

To develop and evaluate a novel polymerase chain reaction (PCR)-enzyme-linked immunosorbent assay (ELISA)-based method for detecting high-oncogenic-risk human papillomaviruses (HPV).

METHODS

An HPV assay based on PCR amplification of a region of the E6 open reading frame and ELISA detection of PCR products that specifically identify high-oncogenic-risk HPV types (eg, types 16, 18, 31, 33, 35, 39, 45, 56, 58, and 65) was developed. Dacron swabs were used to obtain samples from the cervices of 371 women referred for colposcopy. The swabs were analyzed using the PCR-ELISA method. The results of HPV DNA testing were then compared with the results of a repeat Papanicolaou smear and cervical biopsy obtained at the same visit.

RESULTS

The sensitivity of the PCR-ELISA HPV test for detecting invasive cervical cancer or high-grade squamous intraepithelial lesions (SIL) was 90%. High-oncogenic-risk HPVs were detected in six of seven women with biopsy-confirmed invasive cervical cancer, 74 of 81 women with biopsy-confirmed high-grade SIL, 58 of 128 women with biopsy-confirmed low-grade SIL, and 46 of 155 women with no evidence of cervical disease by colposcopy and cervical biopsy. When used in conjunction with a repeat Papanicolaou test, 97% of the women with invasive cervical carcinoma and high-grade SIL lesions were identified.

CONCLUSION

The PCR-ELISA-based HPV detection provides the potential for an automated, rapid, and sensitive test for cervical cancer and high-grade cervical lesions.

Differentiation of Nocardia from rapidly growing Mycobacterium species by PCR-RFLP analysis

The nucleotide sequences from a region of the groEL gene from one Nocardia asteroides and from several species of Mycobacterium were determined and found to be highly homologous. Based on these homologies, we developed a rapid method capable of differentiating between these two genera. The method is based on restriction fragment-length polymorphism (RFLP) analysis of DNA amplified from the groEL gene that is highly conserved between mycobacteria and nocardiae. When the groEL gene from species of these genera is enzymatically amplified by the polymerase chain reaction (PCR), a 422-bp fragment is generated. Correlation of the restriction endonuclease digestion patterns of the amplification products with reference and/or biochemically characterized clinical samples enabled us to establish RFLP profiles for ten species of Mycobacterium and five species of Nocardia. When a portion of the groEL gene from each of these organisms is digested with the restriction endonuclease Hae III, that organism is readily assigned to one of these two genera on the basis of the derived RFLP patterns. The utility of this approach was examined by testing 105 pure cultures from samples previously identified by routine culture techniques for the presence of groEL DNA sequences of mycobacterial or nocardial origin. This analysis correctly identified the organism in all samples tested. In summary, PCR-RFLP analysis provides a rapid and sensitive method for the differentiation of Nocardia species from rapidly growing Mycobacterium species.

A PCR strategy that differentiates two alleles for a single base insertion within a T repeat

PCR amplification with modified primers, in combination with BcgI restriction fragment length polymorphism analysis, allowed us to differentiate a string of 7 Ts present in exon 7 of the 21-hydroxylase gene of man from the 8 Ts present in exon 7 of its pseudogene. This approach can substitute for hybridization with oligonucleotides, or for sequence analysis, when an allele containing a multiple repeated nucleotide sequence is to be differentiated from one with a different number of the identical nucleotide.

Relationship of human papillomavirus type to grade of cervical intraepithelial neoplasia

OBJECTIVE--To determine the relationship of human papillomavirus (HPV) type to grade of cervical intraepithelial neoplasia (CIN) in a large series of cases. DESIGN--A survey of HPV types in CIN lesions detected using a new, highly accurate method for typing HPV that is based on restriction fragment length polymorphism analysis of amplimers produced during polymerase chain amplification of the conserved L1 region of HPV using consensus primers. SETTING--Private gynecologists' offices and inner-city colposcopy clinics. PATIENTS--A convenience sample of 276 HPV DNA-positive cervical biopsy specimens or samples from patients undergoing colposcopy for abnormal Papanicolaou smears. INTERVENTION--None. MAIN OUTCOME MEASURE(S)--Human papillomavirus type(s). RESULTS--Cervical intraepithelial neoplasia 1 lesions were relatively heterogeneous with regard to associated HPV types. Nineteen percent of CIN 1 lesions were associated with HPV types 6 or 11; 29% contained HPV types 16, 18, or 33; and 19% were associated with "novel types" of HPV. It was also found that 22% of CIN 1 lesions were associated with more than one HPV type. In contrast to CIN 1, both CIN 2 and CIN 3 were relatively homogeneous with regard to associated HPV types. Eighty-eight percent of CIN 2 and 3 lesions contained HPV types 16, 18, or 33. Unlike CIN 1 lesions, which often contained multiple types of HPV, only 7% of CIN 2 and 3 lesions were associated with multiple HPV types. CONCLUSIONS--Cervical intraepithelial neoplasia should be classified into two separate categories--low-grade and high-grade CIN. Since only 29% of low-grade lesions are associated with HPV types 16, 18, or 33, HPV type could potentially play a role in determining the most appropriate clinical management of patients with low-grade CIN. However, prospective follow-up studies of lesional behavior based on HPV type are required before clinical recommendations can be made.

Typing of human papillomaviruses by polymerase chain reaction amplification with L1 consensus primers and RFLP analysis

Human papillomaviruses (HPV) cause benign and malignant lesions of the epithelial and mucosal surfaces. Certain virus types are associated with cervical carcinomas, while others are associated with benign condylomata. We have developed a rapid method for determining HPV type that is based on restriction fragment length polymorphism (RFLP) analysis within the L1 region of HPVs that is amplified by PCR using the consensus primers described by Manos et al. Analysis of the product generated by PCR amplification of plasmids containing cloned HPV genomes and of 88 clinical specimens, known to contain HPV viral DNA by previous hybridization analysis, revealed that this method is useful for typing HPV sequences amplified from a variety of sources including cervical lavages, fresh tissue, and paraffin-embedded formalin-fixed biopsy material. The method can differentiate between most known types of HPV and discriminate between infections with single, multiple or novel HPV types. A high correlation (86%) was obtained when this method was compared with PCR amplification and Southern blot hybridization analysis of PCR product, or Southern blot hybridization analysis of total genomic DNA. Differences in typing occurred mostly for specimens that contained multiple or new/unknown HPV types. However, RFLP typing easily identified repeated patterns for new HPV types that were not detected by the other methods. In summary, PCR-RFLP typing is a sensitive and specific method to identify and characterize rapidly HPV DNA in clinical specimens from a variety of sources.

Restriction fragment length polymorphism of polymerase chain reaction products from vaccine and wild-type varicella-zoster virus isolates

The nucleotide changes that result in two restriction endonuclease polymorphisms that differentiate wild-type varicella-zoster virus (VZV) from the vaccine strain were determined. Oligonucleotide primers that flank these sites were used to amplify the intervening sequences with the polymerase chain reaction to identify VZV DNA in clinical isolates. Restriction enzyme digestion of the amplification products distinguished vaccine and wild-type genomes from one another. This study confirms the feasibility of amplifying VZV sequences so that they may be detected in clinical specimens and provides a molecular epidemiological approach to strain identification of VZV in vesicular lesions.

Biologic properties and nucleotide sequence analysis of human papillomavirus type 51

Human papillomaviruses (HPVs) may be grouped according to the site from which they are isolated and the disease with which they are associated. We recently identified and cloned HPV type 51 (HPV-51) from a low-grade precancerous lesion (G. Nuovo, E. DeVilliers, R. Levine, S. Silverstein, and C. Crum. J. Virol. 62:1452-1455, 1988). Molecular epidemiologic analysis of cervical lesions, including condylomata and low- and high-grade precancers, revealed that HPV-51 was present in about 5% of the samples we examined. We have now determined the complete nucleotide sequence of this virus and compared it with other sequenced HPVs. Our analysis reveals that the 7,808-bp genome is composed of eight open reading frames which are encoded on the same strand and that this virus is most closely related to HPV-31. Sequence comparisons place this virus in the group of high-risk viruses (those with an increased risk of progressing to malignancy) along with HPV-16, -18, -31, and -33. Morphologic transformation experiments demonstrated that HPV-51 had transformation potential and that transformed cells contained RNAs homologous to E6 and E7.