Altered Connectivity in Autistic Adults during Complex Facial Emotion Recognition: A Study of EEG Imaginary Coherence.

Difficulties in Facial Emotion Recognition (FER) are commonly associated with individuals diagnosed with Autism Spectrum Disorder (ASD). However, the mechanisms underlying these impairments remain inconclusive. While atypical cortical connectivity has been observed in autistic individuals, there is a paucity of investigation during cognitive tasks such as FER. It is possible that atypical cortical connectivity may underlie FER impairments in this population. Electroencephalography (EEG) Imaginary Coherence was examined in 22 autistic adults and 23 typically developing (TD) matched controls during a complex, dynamic FER task. Autistic adults demonstrated reduced coherence between both short and long range inter-hemispheric electrodes. By contrast, short range intra-hemispheric connectivity was increased in frontal and occipital regions during FER. These findings suggest altered network functioning in ASD.

Biostatistical analysis of quantitative immunofluorescence microscopy images.

Semiquantitative immunofluorescence microscopy has become a key methodology in biomedical research. Typical statistical workflows are considered in the context of avoiding pseudo-replication and marginalising experimental error. However, immunofluorescence microscopy naturally generates hierarchically structured data that can be leveraged to improve statistical power and enrich biological interpretation. Herein, we describe a robust distribution fitting procedure and compare several statistical tests, outlining their potential advantages/disadvantages in the context of biological interpretation. Further, we describe tractable procedures for power analysis that incorporates the underlying distribution, sample size and number of images captured per sample. The procedures outlined have significant potential for increasing understanding of biological processes and decreasing both ethical and financial burden through experimental optimization.

Nelfinavir, efavirenz, or both after the failure of nucleoside treatment of HIV infection.

BACKGROUND: The optimal antiretroviral treatment for patients who have human immunodeficiency virus (HIV) viremia despite treatment with nucleoside reverse-transcriptase inhibitors (nucleoside analogues) remains uncertain. We studied treatment with regimens that combined two nucleoside analogues, at least one of which was new, with the protease inhibitor nelfinavir, the nonnucleoside reverse-transcriptase inhibitor efavirenz, or both. METHODS: The study included 195 patients who had been treated with nucleoside analogues only, and had a plasma HIV type 1 (HIV-1) RNA level of at least 500 copies per milliliter. Patients were randomly assigned to receive, in addition to two nucleoside analogues, nelfinavir, efavirenz, or nelfinavir plus efavirenz. The primary end point was a plasma HIV-1 RNA level of less than 500 copies per milliliter at week 16. A secondary end point was the composite of the HIV-1 RNA levels measured at weeks 40 and 48. RESULTS: At week 16 and at weeks 40 and 48, the proportions of patients in whom a plasma HIV-1 RNA level of less than 500 copies per milliliter was achieved were, respectively, 81 percent and 74 percent in the nelfinavir-plus-efavirenz group, 69 percent and 60 percent in the efavirenz group, and 64 percent and 35 percent in the nelfinavir group. Quadruple therapy resulted in a higher rate of viral suppression in both the short term (P=0.03) and the long term (P=0.001) than did triple therapy with nelfinavir. Triple therapy with efavirenz conferred a higher rate of long-term suppression than triple therapy with nelfinavir (P=0.004). Quadruple therapy also achieved a higher rate of virologic suppression than triple therapy with efavirenz (P=0.008). CONCLUSIONS: In HIV-infected patients previously treated with nucleoside analogues, treatment with nelfinavir plus efavirenz and at least one new nucleoside analogue achieves a higher rate of viral suppression than do regimens with nucleoside analogues and nelfinavir or efavirenz alone.

Multiple modes of calcium-induced calcium release in sympathetic neurons I: attenuation of endoplasmic reticulum Ca2+ accumulation at low [Ca2+](i) during weak depolarization.

Many cells express ryanodine receptors (RyRs) whose activation is thought to amplify depolarization-evoked elevations in cytoplasmic Ca2+ concentration [Ca2+](i) through a process of Ca2+ -induced Ca2+ release (CICR). In neurons, it is usually assumed that CICR triggers net Ca2+ release from an ER Ca2+ store. However, since net ER Ca 2+ transport depends on the relative rates of Ca2+ uptake and release via distinct pathways, weak activation of a CICR pathway during periods of ER Ca accumulation would have a totally different effect: attenuation of Ca2+ accumulation. Stronger CICR activation at higher [Ca2+](i) could further attenuate Ca2+ accumulation or trigger net Ca2+ release, depending on the quantitative properties of the underlying Ca2+ transporters. This and the companion study (Hongpaisan, J., N.B. Pivovarova, S.L. Colgrove, R.D. Leapman, and D.D. Friel, and S.B. Andrews. 2001. J. Gen. Physiol. 118:101-112) investigate which of these CICR "modes" operate during depolarization-induced Ca2+ entry in sympathetic neurons. The present study focuses on small [Ca2+](i) elevations (less than approximately 350 nM) evoked by weak depolarization. The following two approaches were used: (1) Ca2+ fluxes were estimated from simultaneous measurements of [Ca2+](i) and I(Ca) in fura-2-loaded cells (perforated patch conditions), and (2) total ER Ca concentrations ([Ca](ER)) were measured using X-ray microanalysis. Flux analysis revealed triggered net Ca2+ release during depolarization in the presence but not the absence of caffeine, and [Ca2+](i) responses were accelerated by SERCA inhibitors, implicating ER Ca2+ accumulation, which was confirmed by direct [Ca](ER) measurements. Ryanodine abolished caffeine-induced CICR and enhanced depolarization-induced ER Ca2+ accumulation, indicating that activation of the CICR pathway normally attenuates ER Ca2+ accumulation, which is a novel mechanism for accelerating evoked [Ca2+](i) responses. Theory shows how such a low gain mode of CICR can operate during weak stimulation and switch to net Ca2+ release at high [Ca2+](i), a transition demonstrated in the companion study. These results emphasize the importance of the relative rates of Ca2+ uptake and release in defining ER contributions to depolarization-induced Ca2+ signals.

Effect of lamivudine in HIV-infected persons with prior exposure to zidovudine/didanosine or zidovudine/zalcitabine.

Nucleoside analog-based regimens remain an integral component of combination therapy for use in both antiretroviral treatment-naive and experienced HIV-infected patients. To further define treatment responses to new antiretroviral therapy in patients with long-term experience to dual nucleoside analog therapy (zidovudine [ZDV] plus didanosine [ddI] or ZDV plus zalcitabine [ddC]), 325 subjects derived from the AIDS Clinical Trials Group (ACTG) 175 trial were randomized to three different combination regimens: (1) continuation of ZDV + ddI or ZDV + ddC (continuation arm), (2) addition of 3TC to ZDV + ddI or ZDV + ddC (addition arm), or (3) a switch to ZDV + 3TC therapy (switch arm). Both the addition and switch arms sustained significantly greater short-term (baseline to week 4) mean CD4+ cell count increases compared with the continuation arm (+36, +28 versus -4 cells/mm3; p = 0.012) and long-term CD4+ cell count responses (baseline to weeks 40/48: +32, +19 versus -9 cells/mm3; p = 0.003). Superior short-term (baseline to week 8) mean decreases in plasma HIV RNA (p < 0.001) were achieved by both the addition and switch arms (0.53 log10 and 0.54 log10 copies/ml, respectively) compared with the continuation arm (0.13 copies/ml) whereas no differences in long-term virologic suppression were observed (p = 0.30). At week 48, no differences were observed in the proportions of subjects who had HIV RNA levels below 500 copies/mL: 18% of subjects in each treatment arm (3-way p = 1.0). Overall, the treatments were well tolerated and only nine subjects (3%) died or developed one or more AIDS-defining events. While this study confirms the intrinsic antiretroviral activity of 3TC, only modest marker changes and limited short-term viral suppression are seen with incremental addition of the drug. The current approach of using 3TC in maximally suppressive regimens is preferred.

Dissection of mitochondrial Ca2+ uptake and release fluxes in situ after depolarization-evoked [Ca2+](i) elevations in sympathetic neurons.

We studied how mitochondrial Ca2+ transport influences [Ca2+](i) dynamics in sympathetic neurons. Cells were treated with thapsigargin to inhibit Ca2+ accumulation by SERCA pumps and depolarized to elevate [Ca2+(i); the recovery that followed repolarization was then examined. The total Ca2+ flux responsible for the [Ca2+](i) recovery was separated into mitochondrial and nonmitochondrial components based on sensitivity to the proton ionophore FCCP, a selective inhibitor of mitochondrial Ca2+ transport in these cells. The nonmitochondrial flux, representing net Ca2+ extrusion across the plasma membrane, has a simple dependence on [Ca2+](i), while the net mitochondrial flux (J(mito)) is biphasic, indicative of Ca+) accumulation during the initial phase of recovery when [Ca2+](i) is high, and net Ca2+ release during later phases of recovery. During each phase, mitochondrial Ca2+ transport has distinct effects on recovery kinetics. J(mito) was separated into components representing mitochondrial Ca2+ uptake and release based on sensitivity to the specific mitochondrial Na(+)/Ca2+ exchange inhibitor, CGP 37157 (CGP). The CGP-resistant (uptake) component of J(mito) increases steeply with [Ca2+](i), as expected for transport by the mitochondrial uniporter. The CGP-sensitive (release) component is inhibited by lowering the intracellular Na(+) concentration and depends on both intra- and extramitochondrial Ca2+ concentration, as expected for the Na(+)/Ca2+ exchanger. Above approximately 400 nM [Ca2+](i), net mitochondrial Ca2+ transport is dominated by uptake and is largely insensitive to CGP. When [Ca2+](i) is approximately 200-300 nM, the net mitochondrial flux is small but represents the sum of much larger uptake and release fluxes that largely cancel. Thus, mitochondrial Ca2+ transport occurs in situ at much lower concentrations than previously thought, and may provide a mechanism for quantitative control of ATP production after brief or low frequency stimuli that raise [Ca(2+)](i) to levels below approximately 500 nM.

Quantitative analysis of mitochondrial Ca2+ uptake and release pathways in sympathetic neurons. Reconstruction of the recovery after depolarization-evoked [Ca2+]i elevations.

Rate equations for mitochondrial Ca2+ uptake and release and plasma membrane Ca2+ transport were determined from the measured fluxes in the preceding study and incorporated into a model of Ca2+ dynamics. It was asked if the measured fluxes are sufficient to account for the [Ca2+]i recovery kinetics after depolarization-evoked [Ca2+]i elevations. Ca2+ transport across the plasma membrane was described by a parallel extrusion/leak system, while the rates of mitochondrial Ca2+ uptake and release were represented using equations like those describing Ca2+ transport by isolated mitochondria. Taken together, these rate descriptions account very well for the time course of recovery after [Ca2+]i elevations evoked by weak and strong depolarization and their differential sensitivity to FCCP, CGP 37157, and [Na+]i. The model also leads to three general conclusions about mitochondrial Ca2+ transport in intact cells: (1) mitochondria are expected to accumulate Ca2+ even in response to stimuli that raise [Ca2+]i only slightly above resting levels; (2) there are two qualitatively different stimulus regimes that parallel the buffering and non-buffering modes of Ca2+ transport by isolated mitochondria that have been described previously; (3) the impact of mitochondrial Ca2+ transport on intracellular calcium dynamics is strongly influenced by nonmitochondrial Ca2+ transport; in particular, the magnitude of the prolonged [Ca2+]i elevation that occurs during the plateau phase of recovery is related to the Ca2+ set-point described in studies of isolated mitochondria, but is a property of mitochondrial Ca2+ transport in a cellular context. Finally, the model resolves the paradoxical finding that stimulus-induced [Ca2+]i elevations as small as approximately 300 nM increase intramitochondrial total Ca2+ concentration, but the steady [Ca2+]i elevations evoked by such stimuli are not influenced by FCCP.

Scapular fractures in dogs: epidemiology, classification, and concurrent injuries in 105 cases (1988-1994).

A retrospective study of canine scapular fractures diagnosed and treated from 1988 through 1994 at four veterinary teaching hospitals was performed. Dogs (n = 105) with 109 scapular fractures were included. Most scapular fractures occurred in young (i.e., less than four years of age), male, medium- to large-breed (i.e., greater than 10 kg) dogs as the result of vehicular trauma. Concurrent injuries (primarily thoracic trauma) occurred in approximately 70% of cases. In-house follow-up evaluations were considered adequate in only 17% of the cases. A classification system that includes biomechanical principles for categorization is described to avoid discrepancies between various traditional classification systems.

Parasitic sinusitis and otitis in patients infected with human immunodeficiency virus: report of five cases and review.

We describe five cases of parasitic sinusitis and otitis in patients infected with human immunodeficiency virus (HIV) and review 14 reported cases. The pathogens identified in our group of patients included agents such as Microsporidium, Cryptosporidium, and Acanthamoeba species. The clinical features common to these patients included a long history of HIV seropositivity associated with advanced immunosuppression and multiple opportunistic infections as well as long-standing local symptoms refractory to multiple courses of antibacterial agents. Symptoms often included fever and chills in addition to local tenderness and discharge. Invasive diagnostic procedures were necessary to obtain the final diagnosis and to initiate appropriate therapy. Although most patients responded at least partially to specific therapy, relapses and recurrences were frequent in patients who did not receive long-term suppressive therapy. The general outcome for HIV-infected patients with parasitic sinusitis and otitis was poor; however, deaths were generally associated with other complications of the underlying HIV infection.

Legionella bozemanii cavitary pneumonia poorly responsive to erythromycin: case report and review.

A case of pneumonia due to Legionella bozemanii--only the 20th culture-proven case reported so far--progressed with cavitation 9 days after the initiation of intravenous therapy with erythromycin. Review of all 20 reported cases revealed a similar propensity toward radiographic progression (25%) and cavitation (25%) during therapy. A slow response to long courses of erythromycin was the rule (35% of cases). In two instances, long courses of intravenous erythromycin failed and the patient died. Pleural effusion was reported in 60% of patients, including two with empyema. Overall mortality was high (40%). Although mortality was only 21% among patients who lived long enough to receive adequate courses of erythromycin, all three such patients who died had received erythromycin alone. Combination therapy with erythromycin and rifampin proved more effective in terms of survival. Infections due to non-pneumophila Legionella may be overlooked because of the organisms' special serological and culture requirements.

Cytomegalovirus vasculitis. Case reports and review of the literature.

Cytomegalovirus (CMV) infection is a substantial cause of morbidity and mortality among immunocompromised patients. It may present with a mild, self-limited syndrome, retinitis, colitis, or invasive disease with pneumonitis, hepatitis, and bone marrow suppression. We review another, less common manifestation of CMV disease: CMV-associated vasculitis. CMV may productively infect vascular endothelial cells (25), causing a local vasculitis (3, 14, 19) and ischemia. Alternatively, the host immune response to cells expressing viral antigen may be the stimulus for vasculitis (12, 53). Since there are no pathognomonic appearances to mucosal or cutaneous lesions, biopsy of accessible sites is critical for diagnosis and expeditious initiation of appropriate antiviral therapy. The CMV-associated vasculitides represent a broad spectrum of diseases, with GI vasculitis in nontransplant recipients having the best prognosis. Cutaneous vasculitis associated with CMV seems to be a more fulminant disease, with the majority of cases having a fatal outcome. These differences likely reflect the degree of viral burden and the state of immune competence. Additionally, since the virus itself is immunosuppressive, host defenses may be further compromised by the infection. Although a large collective experience assessing the impact of ganciclovir and foscarnet is not currently available, both the prompt initiation of antiviral treatment and a concurrent reduction in any immunosuppressive regimen, including steroids, should be undertaken since these therapeutic strategies have clearly improved outcome for other CMV syndromes (22, 34, 55). As the number of recipients rises and the HIV pandemic spreads we are likely to see an increase in the number of cases of vasculitis associated with CMV infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation of human immunodeficiency virus by herpes simplex virus.

Heterologous viruses have been examined for their ability to accelerate the course of infection with the human immunodeficiency virus (HIV) type 1. In this study, ACH-2 cells persistently infected with HIV-1 exhibited augmented HIV-1 replication as a result of superinfection with herpes simplex virus (HSV) type 1. Using HSV-1 mutants with deletions in the genes encoding immediate-early proteins ICP0, ICP4, and ICP27, it was found that ICP0 and ICP27, but not ICP4, were essential for up-regulation of HIV replication. Northern blot analysis showed that this activation of HIV was characterized by an initial rise in the level of the small, subgenomic (2.0 and 4.3 kb) mRNA species, followed by an increase in the level of unspliced genomic (9.2 kb) mRNA. Such a shift in transcriptional phase recapitulates the early-to-late transition seen in single-step growth curves of acute HIV-1 infection. Thus, HSV can activate HIV-1 from latency in ACH-2 cells, this activation of HIV is independent of productive HSV replication since the delta ICP4 deletion mutant is replication-incompetent, and this activation is evident as an increase in the steady-state levels of HIV transcripts.

The herpes simplex virus immediate-early protein, ICP4, is required to potentiate replication of human immunodeficiency virus in CD4+ lymphocytes.

The interaction of human immunodeficiency virus (HIV) and herpes simplex virus (HSV) was investigated in an acute whole-virus coinfection system. CD4+ lymphoid CEM cells were infected with HIV-1 and, 24 h later, superinfected with HSV-1 (strain KOS) or HSV mutants possessing defined deletions in genes specifying the immediate-early transcriptional regulatory proteins ICP0, ICP4, or ICP27. Marked potentiation of HIV replication was demonstrated with the KOS strain, the ICP0 mutant, and the ICP27 mutant, but not with the ICP4 mutant, indicating that ICP4 is essential and ICP0 and ICP27 are nonessential for this effect. These studies demonstrate that HSV can be a potent stimulator of HIV replication and gene expression in coinfected CD4+ cells through the activity of the HSV regulatory protein ICP4.