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81.
BACKGROUND: Diagnosis of Herpes simplex virus (HSV) infections is achieved by detecting the antigen and isolating the virus from the specimen, which requires 7-28 days. With the recently introduced molecular biological technique of polymerase chain reaction (PCR), the diagnosis of HSV infections has been made more rapid and specific. OBJECTIVE: We evaluated PCR in comparison with the standard laboratory methods on different types of clinical specimens referred to in our laboratory. STUDY DESIGN: A total of 54 specimens, from 54 patients, were investigated. Antigen detection on direct smears was carried out using fluorescent antibody test (FAT) and virus isolation was performed using conventional tube culture method. PCR was carried out with the DNA extracted from various specimens using primers, which coded for the DNA polymerase gene giving a 179 base pair (bp) product. RESULTS: The primers were specific for HSV-1 and HSV-2, and the sensitivity of the primers was found to be 0.5 and 0.2 fg in the detection of HSV-1 and HSV-2 DNA, respectively. Of the 50 specimens (excluding 4 archival formalin fixed tissue specimens, which were not subjected to virological methods of detection) HSV was detected by virological methods and PCR in nine specimens, and by PCR alone in 15 additional specimens, thus increasing the analytical sensitivity significantly by 30% (McNemar test: P = 0.0001). The positivity of PCR in all nine virologically positive specimens and the 4 archival specimens obtained from proven lesions of HSV infections further confirmed the specificity of the PCR. CONCLUSION: PCR, in our study, was found to be a rapid, specific and highly sensitive method for the detection of HSV in clinical specimens.  相似文献   
82.
The nucleotide-binding domain and leucine-rich-repeat-containing (NLR) proteins regulate innate immunity. Although the positive regulatory impact of NLRs is clear, their inhibitory roles are not well defined. We showed that Nlrx1(-/-) mice exhibited increased expression of antiviral signaling molecules IFN-β, STAT2, OAS1, and IL-6 after influenza virus infection. Consistent with increased inflammation, Nlrx1(-/-) mice exhibited marked morbidity and histopathology. Infection of these mice with an influenza strain that carries a mutated NS-1 protein, which normally prevents IFN induction by interaction with?RNA and the intracellular RNA sensor RIG-I, further exacerbated IL-6 and type I IFN signaling. NLRX1 also weakened cytokine responses to the 2009 H1N1 pandemic influenza virus in human cells.?Mechanistically, Nlrx1 deletion led to constitutive interaction of MAVS and RIG-I. Additionally, an inhibitory function is identified for NLRX1 during LPS activation of macrophages where the MAVS-RIG-I pathway was not involved. NLRX1 interacts with TRAF6 and inhibits NF-κB activation. Thus, NLRX1 functions as a checkpoint of overzealous inflammation.  相似文献   
83.
Adrenal lymphangiomas, also known as cystic adrenal lymphangiomas, are rare, benign vascular lesions that usually remain asymptomatic throughout life. Although previously adrenal lymphangioma lesions were primarily found at autopsy, they are currently detected during imaging work-up for unrelated causes and are likely to imitate other adrenocortical or adrenal medullary neoplasms. We aimed to retrospectively review all adrenal lymphangioma cases at our hospital and further document their lymphatic origin by immunohistochemical staining. A search of surgical pathology records (1984-2008) was conducted. All hematoxylin and eosin sections were retrieved from archives and reviewed by 2 pathologists in the study. Clinical information was gathered from electronic medical records. Representative paraffin-embedded sections from each case were selected for immunohistochemical analysis using monoclonal antibodies D2-40 and AE1/AE3. A total of 9 adrenal lymphangioma cases were identified (6 women and 3 men). All 9 patients were adults at time of diagnosis with a mean age of 42 years (range, 28-56 years). There were 7 white patients, 1 African American patient, and 1 Asian patient. The average size of an adrenal lymphangioma lesion was 4.9 cm (range, 2.0-13.5 cm). Adrenal lymphangioma was twice more frequently located on the right side (6 right-sided and 3 left-sided). Clinically, 4 (44%) of the 9 lesions presented with abdominal, flank, or back pain. One lymphangioma was found during work-up for labile hypertension. The remaining 4 lesions (44%) were asymptomatic and incidentally found during imaging studies for unrelated causes. Surgical removal was achieved by total adrenalectomy in 8 of the 9 lesions and by partial adrenalectomy in the remaining case. No evidence of recurrence or development of a contralateral lesion was encountered in any of the patients. Histologically, our adrenal lymphangiomas showed a typical multicystic architecture with dilated spaces lined by flattened, bland, simple lining. The cystic channels/spaces occasionally contained proteinaceous material and lacked red blood cell content. On immunohistochemical stains, D2-40 cytoplasmic staining was positive in all 9 examined lesions, whereas AE1/AE3 was negative, thus, confirming their lymphatic nature. D2-40 staining was diffuse in 2 and focal in the 7 remaining lesions. Adrenal lymphangiomas are very rare, benign lymphatic neoplasms with a female, right-sided predominance in our current series. They may clinically present with abdominal pain or can be incidentally found during adulthood as a mass, necessitating surgical removal to rule out other types of adrenal neoplasms.  相似文献   
84.

Context:

Advances in expertise and equipment have enabled the medical profession to exercise more control over the processes of life and death, creating a number of moral and ethical dilemmas. People may live for extended periods with chronic painful or debilitating conditions that may be incurable.

Aim:

This study attempts to study the attitudes of doctors toward euthanasia and the possible factors responsible for these attitudes.

Settings and Design:

A cross-sectional survey of 213 doctors working at a tertiary care hospital was conducted to determine their attitudes toward euthanasia.

Materials and Methods:

A self-administered questionnaire was used to assess attitudes and personal perceptions about euthanasia.

Statistical Analysis Used:

The Chi square test was used to assess factors influencing attitudes toward euthanasia.

Results:

A majority of the respondents (69.3%) supported the concept of euthanasia. Relief from unbearable pain and suffering was the most commonly (80.3%) cited reason for being willing to consider the option of euthanasia. Majority of those who were against euthanasia (66.2%) felt that the freedom to perform euthanasia could easily be misused. Disapproval of euthanasia was associated with religious affiliation (P<0.001) and speciality (P<0.001).

Conclusions:

A majority of the doctors in this study supported euthanasia for the relief of unbearable pain and suffering. Religion and speciality appear to be significant in determining attitudes toward euthanasia.  相似文献   
85.
Virological monitoring of hepatitis B virus (HBV) DNA is critical to the management of HBV infection. With several HBV DNA quantification assays available, it is important to use the most efficient testing system for virological monitoring. In this study, we evaluated the performance characteristics and comparability of three HBV DNA quantification systems: Abbott HBV real-time PCR (Abbott PCR), artus HBV real-time PCR with QIAamp DNA blood kit purification (artus-DB), and artus HBV real-time PCR with the QIAamp DSP virus kit purification (artus-DSP). The lower limits of detection of these systems were established against the WHO international standards for HBV DNA and were found to be 1.43, 82, and 9 IU/ml, respectively. The intra-assay and interassay coefficients of variation of plasma samples (1 to 6 log(10) IU/ml) ranged between 0.05 to 8.34% and 0.16 to 3.48% for the Abbott PCR, 1.53 to 26.85% and 0.50 to 12.89% for artus-DB, and 0.29 to 7.42% and 0.94 to 3.01% for artus-DSP, respectively. Ninety HBV clinical samples were used for comparison of assays, and paired quantitative results showed strong correlation by linear regression analysis (artus-DB with Abbott PCR, r = 0.95; Abbott PCR with artus-DSP, r = 0.97; and artus-DSP with artus-DB, r = 0.94). Bland-Altman analysis showed a good level of agreement for Abbott PCR and artus-DSP, with a mean difference of 0.10 log(10) IU/ml and limits of agreement of -0.91 to 1.11 log(10) IU/ml. No genotype-specific bias was seen in all three systems for HBV genotypes A, C, and D, which are predominant in this region. This finding illustrates that the Abbott real-time HBV and artus-DSP systems show more comparable performance than the artus-DB system, meeting the current guidelines for assays to be used in the management of hepatitis B.  相似文献   
86.
CSF1R (colony stimulating factor 1 receptor) is the main receptor for CSF1 and has crucial roles in regulating myelopoeisis. CSF1R can be proteolytically released from the cell surface by ADAM17 (A disintegrin and metalloprotease 17). Here, we identified CSF1R as a major substrate of ADAM17 in an unbiased degradomics screen. We explored the impact of CSF1R shedding by ADAM17 and its upstream regulator, inactive rhomboid protein 2 (iRhom2, gene name Rhbdf2), on homeostatic development of mouse myeloid cells. In iRhom2‐/‐ mice, we found constitutive accumulation of membrane‐bound CSF1R on myeloid cells at steady state, although cell numbers of these populations were not altered. However, in the context of mixed bone marrow (BM) chimera, under competitive pressure, iRhom2‐/‐ BM progenitor‐derived monocytes, tissue macrophages and lung DCs showed a repopulation advantage over those derived from wild‐type (WT) BM progenitors, suggesting enhanced CSF1R signaling in the absence of iRhom2. In vitro experiments indicate that iRhom2‐/‐ Lin?SCA‐1+c‐Kit+ (LSKs) cells, but not granulocyte‐macrophage progenitors (GMPs), had faster growth rates than WT cells in response to CSF1. Our results shed light on an important role of iRhom2/ADAM17 pathway in regulation of CSF1R shedding and repopulation of monocytes, macrophages and DCs.  相似文献   
87.
​Multicentric osteolysis nodulosis and arthropathy (MONA) is an infrequently described autosomal recessive skeletal dysplasia characterized by progressive osteolysis and arthropathy. Inactivating mutations in MMP2, encoding matrix metalloproteinase‐2, are known to cause this disorder. Fifteen families with mutations in MMP2 have been reported in literature. In this study we screened thirteen individuals from eleven families for MMP2 mutations and identified eight mutations (five novel and three known variants). We characterize the clinical, radiographic and molecular findings in all individuals with molecularly proven MONA from the present cohort and previous reports, and provide a comprehensive review of the MMP2 related disorders. © 2015 Wiley Periodicals, Inc.
  相似文献   
88.
This study examined the time‐course of reading single words in children and adults using masked repetition priming and the recording of event‐related potentials. The N250 and N400 repetition priming effects were used to characterize form‐ and meaning‐level processing, respectively. Children had larger amplitude N250 effects than adults for both shorter and longer duration primes. Children did not differ from adults on the N400 effect. The difference on the N250 suggests that automaticity for form processing is still maturing in children relative to adults, while the lack of differentiation on the N400 effect suggests that meaning processing is relatively mature by late childhood. The overall similarity in the children's repetition priming effects to adults' effects is in line with theories of reading acquisition, according to which children rapidly transition to an orthographic strategy for fast access to semantic information from print.  相似文献   
89.
90.
In Indian population, hepatitis C virus (HCV) genotypes 1 and 3 are prevalent and predominant with the highest frequency. However, other genotypes are seldom reported, and among them the HCV genotype 5a is exceptionally rare. The presented case had no history for either blood transfusion or using any type of IV drugs and never traveled to any other country. He was serologically positive with HCV antibodies and HCV RNA. 5′UTR-specific amplification and sequencing of infected viral genome confirmed that he had been infected with HCV genotype 5a which is not closely related to other common prevalent genotypes like 1a, 1b, 3a, and 3b in India. Patient’s wife and children tested negative for anti-HCV and HCV-RNA. This unique case report could be attributed to circulation of HCV genotype 5a from other geographic area at very low frequency in India as determined by phylogenetic analysis and nucleic acid-sequencing methods.  相似文献   
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