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81.
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83.

Purpose

Autoantibodies to cytoplasmic structures called rods and rings (RR) are primarily specific to patients with hepatitis C virus (HCV) infection treated with pegylated interferon-alpha/ribavirin (IFN/R). Our aim is to examine anti-RR antibodies specificity and correlation with the response to IFN/R therapy in two independent cohorts (US and Italy) of HCV patients.

Methods

Sera from the US cohort (n?=?47) and the Italian cohort (n?=?46) pre-selected for anti-RR antibodies were analyzed by immunofluorescence and radioimmunoprecipitation. The prevalence and titers of anti-RR were analyzed for correlation with the response to IFN/R therapy.

Results

In the US cohort, anti-RR antibodies were more frequently non-responders to IFN/R (71 % vs 29 % responders). Titers in responder patients (n?=?11) were ≤1:3200, whereas titers in non-responder patients (n?=?27) reached 1:819,200 (p?=?0.0016). In the Italian cohort, anti-RR titers ranged from 1:200 to >1:819,200 and only relapsers had the highest anti-RR titers. Radioimmunoprecipitation demonstrated that anti-RR autoantibodies were mainly anti-inosine monophosphate dehydrogenase 2 (IMPDH2) - 96 % in the Italian cohort vs. 53 % in the US cohort.

Conclusions

In the two cohorts analyzed, the anti-IMPDH2 response as a component of the anti-RR response is much more prominent in the Italian cohort. The reason for the difference between the US and Italian cohorts is unclear but it possibly illustrates the heterogeneity in response and the overall negative correlation between the production of these autoantibodies and response to IFN/R therapy. Patients with high titer anti-RR antibodies are either relapsers (Italian) or non-responders/relapsers (US).  相似文献   
84.
To determine whether ultrasonographic findings can predict the karyotype of spontaneous abortions, 137 pregnancies (54 spontaneous, 83 assisted ovulatory cycles) that subsequently aborted and had chromosome analysis performed on the products of conception were studied ultrasonographically. Transvaginal ultrasound was performed using an Acuson 128XP/10 with 7.5 MHz probe. The numbers of empty gestational sacs, small and normal for gestational size, embryonic poles and embryos with documented cardiac activity were calculated. The frequency of each of these findings in pregnancies with normal and abnormal karyotypes was compared. Of the 137 spontaneous abortions, 51 had normal chromosome analyses and 86 had abnormal karyotypes (68 aneuploidies and 18 polyploidies). Ultrasonographic findings in the 51 karyotypically normal pregnancies included 16 (31%) with empty gestational sacs, and 35 (69%) with embryonic poles, of which 24 (69%) were at least 1 week smaller than expected for gestational age and 11 (31%) were the expected size. Embryonic cardiac activity was documented in 22 (63%) of the 35 embryonic poles. Amongst 86 pregnancies with abnormal karyotypes, similar frequencies of ultrasound findings were found: 23 (27%) with empty gestational sacs, 42 (67%) with embryonic poles smaller than expected for gestational age, and 50 (79%) embryos lost after documentation of embryonic cardiac activity. No differences in the frequency of ultrasonographic findings of empty gestational sacs, small embryonic pole and embryonic cardiac activity were observed between karyotypically normal and abnormal spontaneous abortions. Ultrasonographic findings cannot predict the karyotype of spontaneous abortions.   相似文献   
85.
I reviewed the empirical literature for 1900–2008 on the paraphilia of Sexual Masochism for the Sexual and Gender Identity Disorders Work Group for the forthcoming fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. The results of this review were tabulated into a general summary of the criticisms relevant to the DSM diagnosis of Sexual Masochism, the assessment of Sexual Masochism utilizing the DSM in samples drawn from forensic populations, and the assessment of Sexual Masochism using the DSM in non-forensic populations. I concluded that the diagnosis of Sexual Masochism should be retained, that minimal modifications of the wording of this diagnosis were warranted, and that there was a need for the development of dimensional and structured diagnostic instruments. It should be noted that this summary reflects my original literature review. Subsequently, interactions with other members of the workgroup and advisors have resulted in modification of these initial suggestions.  相似文献   
86.
Previous studies have reported the presence of neuronal progenitors in the subventricular zone (SVZ) and rostral migratory stream (RMS) of the postnatal mammalian brain. Although many studies have examined the survival and migration of progenitors after transplantation and the factors influencing their proliferation or differentiation, no information is available on the electrophysiological properties of these progenitors in a near-intact environment. Thus we performed whole cell and cell-attached patch-clamp recordings of progenitors in brain slices containing either the SVZ or the RMS from postnatal day 15 to day 25 mice. Both regions displayed strong immunoreactivity for nestin and neuron-specific class III beta-tubulin, and recorded cells displayed a morphology typical of the neuronal progenitors known to migrate throughout the SVZ and RMS to the olfactory bulb. Recorded progenitors had depolarized zero-current resting potentials (mean more depolarized than -28 mV), very high input resistances (about 4 GOmega), and lacked action potentials. Using the reversal potential of K+ currents through a cell-attached patch a mean resting potential of -59 mV was estimated. Recorded progenitors displayed Ca2+-dependent K+ currents and TEA-sensitive-delayed rectifying K+ (KDR) currents, but lacked inward K+ currents and transient outward K+ currents. KDR currents displayed classical kinetics and were also sensitive to 4-aminopyridine and alpha-dendrotoxin, a blocker of Kv1 channels. Na+ currents were found in about 60% of the SVZ neuronal progenitors. No developmental changes were observed in the passive membrane properties and current profile of neuronal progenitors. Together these data suggest that SVZ neuronal progenitors display passive membrane properties and an ionic signature distinct from that of cultured SVZ neuronal progenitors and mature neurons.  相似文献   
87.
Impaired T-cell immune reconstitution is a major complication after allogeneic bone marrow transplantation (BMT) and is particularly exacerbated in the setting of graft-versus-host disease (GVHD). Conventional approaches to reduce GVHD, such as T-cell depletion or pharmacologic immunosuppression, typically fail to enhance T-cell immunity and often further exacerbate this problem. An alternative strategy to mitigate GVHD severity is the selective elimination of graft-versus-host-reactive donor T cells by using an incorporated thymidine kinase suicide gene. This approach has been shown to effectively reduce GVHD, although the effect of this strategy on T-cell reconstitution is unresolved. We addressed this question in a murine BMT model (C57BL/6 [H-2(b)] --> AKR/J [H-2(k)]) in which donor and recipient differ at major and minor histocompatibility antigens. Lethally irradiated AKR recipients transplanted with T cell-depleted bone marrow plus thymidine kinase-positive T cells followed by post-BMT ganciclovir (GCV) administration had more prompt and complete normalization of the T-cell repertoire than phosphate-buffered saline-treated GVHD control animals. By 60 days after transplantation, mice administered GCV had T-cell repertoires that were virtually indistinguishable from those of mice that underwent transplantation with T cell-depleted bone marrow alone (no GVHD controls) when assayed by T-cell receptor (TCR) spectratyping. In contrast, phosphate-buffered saline-treated animals had persistent skewing in most Vbeta families. T cells obtained from GCV-treated mice also had significantly higher in vitro proliferative responses after posttransplantation inoculation with ovalbumin than GVHD animals, indicating that CD4(+) T-cell responses against a nominal antigen were better preserved in these chimeras. Finally, GCV-treated mice had augmented immune reconstitution in response to exogenous interleukin-7 administration, as evidenced by increased overall spleen cellularity and absolute numbers of T and B cells. This was in contrast to GVHD control animals, which had a blunted response to interleukin-7 administration. These data indicate that GVHD severity can be significantly reduced by selective elimination of alloreactive donor T cells without compromise of T-cell immunity. Moreover, in light of previous studies demonstrating that this strategy can reduce GVHD without loss of alloengraftment and antileukemia reactivity, further examination of this approach in humans seems warranted.  相似文献   
88.
Intercellular adhesion molecule-1 (ICAM1) acts as ligand for beta2-integrin molecules and mediates leucocyte trafficking to the site of inflammation. Intercellular adhesion molecule-1-deficient mice show impaired lymphocyte recruitment to the lung, less airway hyper-responsiveness and less lung inflammation than healthy controls. Thus, the aim of the study was to test common ICAM1 polymorphisms for association with paediatric asthma. Furthermore, we were interested in whether soluble ICAM1 (sICAM1) serum levels were in correlation with genotypes. The following polymorphisms in ICAM1 were genotyped on 352 children with asthma and 270 controls: rs5491 (resulting in the amino-acid exchange K56M), rs5493 (G241S), rs5498 (K469E), rs5030400 (R478W) and rs885743 in the 3'-untranslated region. In addition, sICAM1 serum levels were measured. Only K469E and rs885743 were present in our populations. K469E showed association with asthma (P = 0.0037 with Armitage's trend test). Haplotype analysis by FAMHAP using both polymorphisms revealed association with asthma by P < 0.000001. In addition, serum sICAM1 levels were correlated with K469E genotypes (P = 0.009 by Kruskal-Wallis test). We conclude from our data that K469KE is associated with paediatric asthma in the German population. Furthermore, the same polymorphism is correlated with serum levels of sICAM1. Functional analyses have to further clarify the pathophysiological mechanism conferred by the polymorphisms.  相似文献   
89.
High-risk injection drug use and its accompanying sexual behaviors have large social and financial costs. However, little is known about how age and age at first drug use are related to high-risk injection or sex behaviors. The current study draws on life course perspectives and data from the NIDA Cooperative Agreement to examine the relationship between eight high-risk behavior variables and age and age at first drug use. Random effects negative binomial regression models reveal that the frequency of high-risk sexual behaviors in the past month decreases up to 28% with each decade of age, although the frequency of high-risk injection behaviors in the past month increases by up to 62% with each decade of age. Both high-risk injection and high-risk sex behaviors are lower among those who initiated first drug use at later ages. Previous research has indicated the importance of interventions to reduce the high-risk sexual behaviors of older drug users. The current study suggests a refocusing of public health efforts on their high-risk injection habits.  相似文献   
90.
Hepatic Infarction Associated with Eclampsia   总被引:3,自引:0,他引:3  
Pregnancy-related liver diseases are complex in presentation and oftentimes confusing to clinicians, leading to misdiagnoses and unwarranted or delayed therapies. The exact pathogenesis of these disorders and their relationship to preeclampsia/eclampsia is unclear, thus making categorization difficult. We present a patient who in the third trimester of pregnancy developed severe abdominal pain, fever and transaminases greater than 30 times normal. The patient's laboratory data, abdominal CT scan, abdominal MRI scan, liver-spleen scan and liver biopsy performed 28 days postpartum subsequently confirmed the diagnosis of hepatic infarction. Hepatic infarction is a rare complication of late pregnancy usually associated with severe eclampsia that has distinctive histologic and laboratory findings. Recognition of infarction as a separate entity among the spectrum of the pregnancy-related liver disorders should help avoid unneeded delay in diagnosis or inappropriate treatment of these critically ill patients.  相似文献   
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