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1.
BACKGROUND: Cytomegalovirus (CMV) infection and Kaposi's sarcoma (KS) are common in AIDS patients but rarely involve the thyroid, and coexistence of these two entities in that organ has not yet been described before. CASE: A 41-year-old female AIDS patient presented with a 2 x 1-cm, well-demarcated, rubbery mass in the right side of the thyroid. On fine needle aspiration (FNA), spindle cells were retrieved singly or in small, loose clusters; they had bland, fusiform to cigar-shaped nuclei; inconspicuous nucleoli; delicate cytoplasmic vacuoles; cytoplasmic hyaline drops; and hemosiderin granules. A single endothelial cell showed an enlarged nucleus with a basophilic intranuclear inclusion and periinclusional halo. CONCLUSION: This is the first reported case of an AIDS patient with KS and CMV infection simultaneously involving the thyroid diagnosed by FNA.  相似文献   

2.
Healthy young children who acquire CMV have prolonged viral shedding into the urine and saliva, but whether this is attributable to limitations in viral-specific immune responses has not been explored. In this study, we found that otherwise immunocompetent young children after recent primary CMV infection accumulated markedly fewer CMV-specific CD4(+) T cells that produced IFN-gamma than did adults. These differences in CD4(+) T cell function persisted for more than 1 year after viral acquisition, and did not apply to CMV-specific IFN-gamma production by CD8(+) T cells. The IFN-gamma-producing CD4(+) T cells of children or adults that were reactive with CMV Ags were mainly the CCR7(low) cell subset of memory (CD45R0(high)CD45RA(low)) cells. The decreased IFN-gamma response to CMV in children was selective, because their CCR7(low) memory CD4(+) T cells and those of adults produced similar levels of this cytokine after stimulation with staphylococcal enterotoxin B superantigen. CD4(+) T cells from children also had reduced CMV-specific IL-2 and CD154 (CD40 ligand) expression, suggesting an early blockade in the differentiation of viral-specific CD4(+) T cells. Following CMV acquisition, children, but not adults, persistently shed virus in urine, and this was observable for at least 29 mo postinfection. Thus, CD4(+) T cell-mediated immunity to CMV in humans is generated in an age-dependent manner, and may have a substantial role in controlling renal viral replication and urinary shedding.  相似文献   

3.
S. Mandal, and S. Jain
Adenoid cystic pattern in follicular variant of papillary thyroid carcinoma: a report of four cases Objective: An adenoid cystic pattern in thyroid tumours is a rare finding that may be seen in papillary carcinoma of thyroid (PCT), the follicular variant of PCT (FV‐PCT), a rare cribriform‐morular variant of papillary carcinoma of thyroid (CMV‐PCT) and follicular carcinoma. There is little published cytological literature describing these patterns. We report four cases of PCT with this unusual pattern. Methods: Fine needle aspiration (FNA) cytology was performed on four patients with a neck lump using a 22‐G needle; smears were stained with Giemsa and Papanicolaou stains. Immunocytochemical staining for thyroglobulin was done in all cases. Results: The patients were female and ranged in age from 18 to 46 years. They presented with a gradually increasing mass in the neck. FNA smears in all cases showed nuclear features of PCT. There were also prominent follicular areas with hyaline globules in some of the cell clusters reminiscent of adenoid cystic carcinoma and, in places, morula‐like groups of neoplastic cells were also seen. Immunocytochemistry for thyroglobulin was positive in all cases but negative in the hyaline globules. Conclusions: Adenoid cystic areas with morula‐like groups in PCT are a rare finding. Cytopathologists and clinicians should be aware of these distinct features in thyroid tumours to avoid diagnosing metastatic adenoid cystic carcinoma. It is also important to rule out CMV‐PCT since that variant is mostly associated with familial adenomatous polyposis, although sporadic occurrence is known.  相似文献   

4.
Characterization of the human newborn response to herpesvirus antigen   总被引:5,自引:0,他引:5  
An investigation was made into the human newborn cellular response to herpes simplex virus type 1 (HSV), cytomegalovirus (CMV), and varicella zoster virus (VZV) to understand more about the nature of the neonate's susceptibility to overwhelming infection by these viruses. Newborn mononuclear cells sustained the proliferation in culture of maternal (i.e., haplotype-matched) T cell blasts with specificity for HSV, CMV, or VZV (p less than 0.05). This is evidence for intact antigen-processing capability by newborn monocytes. The response of the maternal T cell blasts appeared to be HLA-haplotype-restricted as suggested by experiments in which maternal T cell blasts were limited in number. Our culture conditions elicited responses predominantly from the T4+ lymphocyte subset. A low frequency of herpesvirus-specific T4+ lymphocytes in newborn blood might contribute to deficient viral immunity, so we evaluated the virus-specific T cell responding frequency in human newborns in limiting dilution cultures. We were unable to find a herpesvirus-specific responder cell frequency greater than 1:1,400,000 in nonimmune newborns. Three of seven adults who had no serum antibody to CMV had a CMV responder cell frequency (RCF) of 1:100,000 to 1:200,000. The RCF to HSV in immune children, ages 18 mo to 12 yr, and adults, ages 13 to 80 yr, ranged from 1:14,000 to 1:18,000. We conclude that newborn monocyte processing of herpesvirus antigen is intact, that T cell RCF is low in neonates, and that immunity to HSV after infection outside the newborn period results in comparable RCF between adults and children.  相似文献   

5.
Cytomegalovirus (CMV) is the cause of a number of different diseases ranging from self-limited benign infections in healthy adults to life threatening illnesses among immunocompromised hosts and newborns. Suppression of cell-mediated immunity is often found in cases of acute CMV infection, and in addition, the virus may also be a potent stimulant of lymphoid cells in vivo. We studied cellular proliferation and immunoglobulin (Ig) production induced by CMV to determine its effect on human lymphocytes in vitro. The CMV that was added to cultures of lymphocytes from CMV-seronegative donors failed to induce either significant cellular proliferation or Ig production. By contrast, CMV-stimulated cultures from CMV-seropositive donors induced both prominent cellular proliferation and Ig production. B cell differentiation into Ig-secreting cells required the presence of T cells, and this T cell help was sensitive to irradiation with 2000 rad and to treatment with cyclosporin A. When T cells were depleted of OKT4+ cells with monoclonal antibody and complement, the co-cultured B cells failed to produce Ig, whereas the depletion of OKT8+ cells had no effect on the Ig-secreting cell response. Inactivation of CMV before culture did not result in a reduction of either cellular proliferation or Ig production. Thus, infection of target cells is not required for in vitro lymphocyte activation by CMV. These results demonstrate that CMV is a potent activator of B cells inducing Ig production in vitro, and that this process requires the presence of virus-specific memory T cells.  相似文献   

6.
《Endocrine practice》2021,27(3):261-268
ObjectiveContextualizing the evaluation of older adults with thyroid nodules is necessary to fully understand which management strategy is the most appropriate. Our goal was to summarize available clinical evidence to provide guidance in the care of older adults with thyroid nodules and highlight special considerations for thyroid nodule evaluation and management in this population.MethodsWe conducted a literature search of PubMed and Ovid MEDLINE from January 2000 to November 2020 to identify relevant peer-reviewed articles published in English. References from the included articles as well as articles identified by the authors were also reviewed.ResultsThe prevalence of thyroid nodules increases with age. Although thyroid nodules in older adults have a lower risk of malignancy, identified cancers are more likely to be of high-risk histology. The goals of thyroid nodule evaluation and the tools used for diagnosis are similar for older and younger patients with thyroid nodules. However, limited evidence exists regarding thyroid nodule evaluation and management to guide personalized decision making in the geriatric population.ConclusionConsidering patient context is significant in the diagnosis and management of thyroid nodules in older adults. When making management decisions in this population, it is essential to carefully weigh the risks and benefits of thyroid nodule diagnosis and treatment, in view of older adults’ higher prevalence of high-risk thyroid cancer as well as increased risk for multimorbidity, functional and cognitive decline, and treatment complications.  相似文献   

7.
Plant virus infections are known to alter host plant attractiveness and suitability for insect herbivores.This study was conducted to determine how cucumber mosaic virus (CMV)-infected chilli plants affect the fitness and settling preferences ofnonvector whitefly,Bemisia tabaci adults under dual-choice conditions with volatile organic compounds analyzed using solid phase microextraction coupled with gas chromatography-mass spectrometry (GC-MS).Results showed that the presence of CIVIV in chilli plants substantially affects the settling preferences of the B.tabaci,which preferred to settle on noninfected plants.Duration of the egg stage and the longevity and fecundity of adult B.tabaci on CMV-infected chilli plants were not markedly different from those on noninfected chilli plants.In contrast,the developmental time from egg to adult was significantly reduced in CMV-infected chilli plants compared to the noninfected plants.The results also showed that CMV-infected chilli plants released significantly more linalool and phenylacetaldehyde than noninfected plants.Overall,it was suggested that the behavioral response of B.tabaci might be modified by CMV-infected plants,which alter the release of specific headspace volatiles.Based on these results,the modification of plant volatile profiles may help in enhancing the effectiveness of biological control and the protection of crop plants against B.tabaci.  相似文献   

8.
Infants or children who had congenital or neonatal infection with cytomegalovirus (CMV) or herpes simplex virus (HSV) have fewer than 1:30,000 mononuclear cells in their blood lymphocytes preparations that proliferate in cultures stimulated with the corresponding viral antigens. CMV and HSV responder cell frequencies in children and adults whose immunity followed postnatal infection with these viruses are 1:10,000 to 1:20,000. The low precursor frequency after congenital or neonatal infection is not associated with defective antigen processing by monocytes or nonspecific immunosuppression. Phenotypic changes in T cell subsets and the presence of antibody in the subjects suggests that the virus(es) do indeed elicit an immune response, but that this response is quantitatively deficient.  相似文献   

9.
Based on the results of131I thyroid activity measurements in three districts of the Chernigov region (Ukraine), individual doses were calculated and an approach of the age dependence of the average thyroid exposure was derived. Using the relationships between the thyroid doses and the137Cs deposition as well as the location relative to the Chernobyl Nuclear Power Plant (NPP), age-dependent average thyroid doses were extrapolated also for those settlements of this region where no monitoring measurements have been carried out. The highest doses were found in the west of the region with the lowest distance to the Chernobyl NPP. In this part, the highest mean of the thyroid dose in a settlement was 3.3 Gy for infants and 0.5 Gy for adults. The collective thyroid dose was 31000 and 27 000 person-Gy for children and adults, respectively. Based on this assessment, 140 and 21 excess thyroid cancer cases are predicted for children and adults, respectively. In the years 1989 to 1991, in the whole contaminated territory of the Ukraine 0.4–1.2 cases per 100000 children were observed. Although the absolute numbers are very small, this indicates the possibility of an increase in thyroid cancer morbidity among children. The same trend also seems to be indicated in the Chernigov region. A careful epidemiological study in the future is necessary to enable a final evaluation of radioinduced cancers in this region.  相似文献   

10.
11.
《Endocrine practice》2021,27(12):1260-1263
The state of thyroid cancer in 2021 is reviewed including the prevalence of thyroid cancer, vulnerable patient groups such as women and young adults, and known and hypothesized risk factors for thyroid cancer. Understanding the overdiagnosis and overtreatment of thyroid cancer and recent efforts to reduce harms secondary to overdiagnosis and overtreatment are addressed with optimism that future work will continue to evaluate and improve the care of patients with thyroid cancer.  相似文献   

12.

Background

Reactivation of cytomegalovirus (CMV) has been reported occasionally in immnunocompetent patients in the intensive care unit (ICU). The epidemiology and association of CMV infection with adverse outcome is not well defined in this population. Patients undergoing major heart surgery (MHS) are at a particularly high risk of infection. CMV infection has not been systematically monitored in MSH-ICU patients.

Methods

We assessed CMV plasma viremia weekly using a quantitative polymerase chain reaction assay in a prospective cohort of immunocompetent adults admitted to the MHS-ICU for at least 72 hours between October 2012 and May 2013. Risk factors for CMV infection and its potential association with continued hospitalization or death by day 30 (composited endpoint) were assessed using univariate and multivariate logistic regression analyses.

Results

CMV viremia at any level was recorded in 16.5% of patients at a median of 17 days (range, 3-54 days) after admission to the MHS-ICU. Diabetes (adjusted OR, 5.6; 95% CI, 1.8-17.4; p=0.003) and transfusion requirement (>10 units) (adjusted OR, 13.7; 95% CI, 3.9-47.8; p<0.001) were independent risk factors associated with CMV reactivation. Reactivation of CMV at any level was independently associated with the composite endpoint (adjusted OR, 12.1; 95% CI, 2.3-64; p=0.003).

Conclusion

Reactivation of CMV is relatively frequent in immunocompetent patients undergoing MHS and is associated with prolonged hospitalization or death.  相似文献   

13.
Cytomegalovirus (CMV) has been suggested as the most prevalent infectious agent causing neurological dysfunction in the developing brain; in contrast, CMV infections are rare in the adult brain. One explanation generally given for the developmental susceptibility to the virus is that the developing immune system is too immature to protect the central nervous system from viral infection, but as the immune system develops it can protect the brain. We suggest an alternate view: that developing brain cells are inherently more susceptible to CMV infection, independent of the immune system. We used a recombinant mouse CMV that leads to green fluorescent protein expression in infected cells. Control experiments demonstrated a high correlation between the number of cells detected with the viral GFP reporter gene and with immunocytochemical detection of the virus. After intracerebral inoculation, the number of CMV-infected cells in neonatal brains was many times greater than in mature control or mature immunodepressed SCID mice, and the mortality rate of neonates was substantially greater than SCID or control adults. Parallel experiments with live brain slices inoculated in vitro, done in the absence of the systemic immune system, generated similar data, with immature hippocampus, hypothalamus, cortex, striatum, and cerebellum showing substantially greater numbers of infected cells (100-fold) than found in adult slices in these same regions. Interestingly, in the cerebellar cortex, CMV-infected cells were more prevalent in the postmitotic Purkinje cell layer than in the mitotic granule cell layer, suggesting a selective infection of some cell types not dependent on cell division. Together, these data support the view that CMV has an intrinsic preference for infection of developing brain cells, independent, but not mutually exclusive, of the developmental status of the systemic immune system in controlling CMV infection.  相似文献   

14.
Iodothyronine content in the pig thyroid gland   总被引:2,自引:0,他引:2  
An analysis has been carried out on the contents and reciprocal proportions of three principal iodothyronines (T4, T3 and rT3) in the thyroids of fed and fasted piglets of 8-10 wk and in adult pigs. The mean T4 concentration averaged 62.0 +/- nmol/100 mg wet tissue (in adults: 18.5 +/- 4.3 nmol/100 mg tissue); T3, 9.5 +/- 0.9 nmol/100 mg tissue (in adults: 1.58 +/- 0.2 nmol/100 mg tissue); rT3, 3.0 +/- 0.3 nmol/100 mg tissue. The reciprocal ratios of the hormones in the piglets' thyroids were: for T3:T4, 0.150 (in adults, 0.114) and for rT3:T4, 0.050 (in adults, 0.023). Mean T4:T3:rT3 ratio in piglets and adult pigs was 20.5:3.1:1 and 66.1:5.6:1, respectively. The results from all examined iodothyronines, show the higher absolute concentration in piglets' than in adult pigs' thyroid tissue, while the reciprocal proportions of the hormones reveal smaller T4 thyroid contents (comparing with T3 and rT3) in piglets than in adults. No changes of absolute thyroidal contents or reciprocal ratios of the iodothyronines were observed in fed and fasted piglets. In a comparison, the pig thyroid contains more triiodothyronine and a higher ratio T3:T4 than that in some other species.  相似文献   

15.

Background

Cytomegalovirus (CMV) viremia has been shown to be an independent risk factor for increased mortality among HIV-infected individuals in the developing world. While CMV infection is nearly ubiquitous in resource-poor settings, few data are available on the role of subclinical CMV reactivation on HIV.

Methods

Using a cohort of mineworkers with stored plasma samples, we investigated the association between CMV DNA concentration and mortality prior to antiretroviral therapy availability.

Results

Among 1341 individuals (median CD4 count 345 cells/µl, 70% WHO stage 1 or 2, median follow-up 0.9 years), 70 (5.2%) had CMV viremia at baseline; 71 deaths occurred. In univariable analysis CMV viremia at baseline was associated with a three-fold increase in mortality (hazard ratio [HR] 3.37; 95% confidence intervals [CI] 1.60, 7.10). After adjustment for CD4 count, WHO stage and HIV viral load (N = 429 with complete data), the association was attenuated (HR 2.27; 95%CI 0.88, 5.83). Mortality increased with higher CMV viremia (≥1,000 copies/ml vs. no viremia, adjusted HR 3.65, 95%CI: 1.29, 10.41). Results were similar using time-updated CMV viremia.

Conclusions

High copy number, subclinical CMV viremia was an independent risk factor for mortality among male HIV-infected adults in South Africa with relatively early HIV disease. Studies to determine whether anti-CMV therapy to mitigate high copy number viremia would increase lifespan are warranted.  相似文献   

16.

Background

Elevated levels of antibodies to Cytomegalovirus (CMV) have been associated with cognitive impairment, but the quantitative relationship between CMV antibody levels and domains of cognitive functioning in younger adults has not been established.

Methods

We measured IgG class antibodies to Cytomegalovirus in 521 individuals, mean age 32.8 years. Participants were selected for the absence of psychiatric disorder and of a serious medical condition that could affect brain functioning. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Wisconsin Card Sorting Test, Trail Making Test part A, and the WAIS III Letter Number Sequencing subtest. Linear regression analyses were used to measure the quantitative association between cognitive scores and Cytomegalovirus IgG antibody level. Logistic regression analyses were used to measure the odds of low cognitive scores and elevated antibody levels defined as an antibody level > = 50th, 75th, and 90th percentile of the group.

Results

Higher levels of CMV antibodies were associated with lower performance on RBANS Total (coefficient −1.03, p<.0002), Delayed Memory (coefficient −0.94, p<.001), Visuospatial/Constructional (coefficient −1.77, p<5×10−7), and Letter Number Sequencing (coefficient −0.15, p<.03). There was an incremental relationship between the level of CMV antibody elevation and the odds of a low RBANS Total score. The odds of a low total cognitive score were 1.63 (95th % CI 1.01, 2.64; p<.045), 2.22 (95th % CI 1.33, 3.70; p<.002), and 2.46 (95th % CI 1.24, 4.86; p<.010) with a CMV antibody level greater than or equal to the 50th, 75th, and 90th percentile respectively.

Conclusions

Higher levels of Cytomegalovirus antibodies are associated with lower levels of cognitive functioning in non-elderly adults. Methods for the prevention and treatment of CMV infection should be evaluated to determine if they result in an improvement in cognitive functioning in otherwise healthy adults.  相似文献   

17.
The thyroid cancer data of children in the northern regions of the Ukraine after the reactor accident at Chernobyl were combined with thyroid dose measurements in the same regions and analysed using a two- mutation carcinogenesis model. The best fit was obtained for radiation acting as an initiating agent, i.e. on the first mutation of the model. The observed relatively high increase of thyroid cancer incidence after 1990 in children exposed to radiation released after the reactor accident could be ascribed to the high thyroid doses and the relatively low background thyroid cancer incidence in children. The maximum annual incidence is predicted to occur fairly soon after the reactor accident, i.e. about 10 years. For adults, the predicted relative increase of annual thyroid cancers is much lower than for children younger than 20 years. The modelling results are used to derive risk estimates for radiation-induced thyroid cancer. These risk estimates are dependent on age at exposure, follow-up time and the background thyroid cancer incidence. The calculated excess absolute risk for a population of all ages is about one-third of that currently used by ICRP, but for children the calculated absolute risks are about a factor of 3 higher than derived in other epidemiological studies. The model results indicate that the excess absolute radiation risk per unit dose for children is about the same as or a little lower than that for adults. Received: 11 May 1999 / Accepted: 30 December 1999  相似文献   

18.
Spontaneous primary hypothyroidism in adults is usually associated with autoimmune thyroiditis. The hypothesis that hypothyroidism may result from the presence in serum of a factor that blocks stimulation of the thyroid by thyroid stimulating hormone was examined. Serum samples were collected from 28 patients with recently diagnosed primary hypothyroidism. After removal of endogenous thyroid stimulating hormone the effect of the serum on secretion of triiodothyronine induced by thyroid stimulating hormone or thyroid stimulating antibodies was examined in thyroid slices incubated in vitro. Serum samples from six of the patients demonstrated significant blocking of the stimulation by bovine thyroid stimulating hormone. Inhibition of the stimulatory action of thyroid stimulating antibodies was also exhibited by serum samples with blocking activity. It is concluded that in some patients with primary hypothyroidism a serum factor, which is probably an IgG, exists that can block the thyroid response to thyroid stimulating hormone and thyroid stimulating antibodies; it may represent an important mechanism in the pathogenesis of hypothyroidism.  相似文献   

19.
In a study at a primary care centre in a predominantly rural area of Sweden the records of all patients with established thyroid disease were scrutinised and 2000 consecutive adult patients screened with an immunoenzymometric thyroid stimulating hormone assay. The aims of the study were fourfold: firstly, to assess the total burden of thyroid disease in primary care centres in Sweden; secondly, to assess the efficacy of clinical diagnosis of the disease in unselected populations of patients; thirdly, to assess the efficacy of clinical evaluation of treatment with thyroxine; and, lastly, to see whether a single analysis of the serum thyroid stimulating hormone concentration by recent methods would be enough to identify an abnormality of thyroid function. Of the roughly 17,400 adults in the study community, 111 women and 10 men were being treated for thyroid disease. Screening detected 68 patients (3.5%) not receiving thyroxine who had a serum thyroid stimulating hormone concentration of 0.20 mU/l or less, all of whom were followed up clinically. Fifty of these patients were also studied biochemically during follow up. Only nine of the 68 patients had thyroid disease (three with thyrotoxicosis requiring treatment), no evidence of the disease being found in the remainder. Sixteen patients had spontaneous hypothyroidism requiring treatment, and neither these nor three patients with thyrotoxicosis had been detected at the preceding clinical examination. Of 35 patients in whom thyroid disease was suspected clinically at screening, none had laboratory evidence of thyroid dysfunction. In this series 1.3% of all women in the study community (2.6% of all 50-59 year olds) and 0.1% of the men were being treated for thyroid disease at the primary care centre, roughly 1.0% of adults subjected to screening were found to have thyroid disease requiring treatment, and most patients with a thyroid stimulating hormone concentration of 0.20 mU/l or less did not have thyroid dysfunction. It is concluded that measuring the basal serum thyroid stimulating hormone concentration by present methods is insufficient for the biochemical assessment of thyroid dysfunction in unselected populations.  相似文献   

20.

Background

We examined the effect of cytomegalovirus (CMV) co-infection and viremia on reconstitution of selected CD4+ and CD8+ T-cell subsets in perinatally HIV-infected (PHIV+) children ≥ 1-year old who participated in a partially randomized, open-label, 96-week combination antiretroviral therapy (cART)-algorithm study.

Methods

Participants were categorized as CMV-naïve, CMV-positive (CMV+) viremic, and CMV+ aviremic, based on blood, urine, or throat culture, CMV IgG and DNA polymerase chain reaction measured at baseline. At weeks 0, 12, 20 and 40, T-cell subsets including naïve (CD62L+CD45RA+; CD95-CD28+), activated (CD38+HLA-DR+) and terminally differentiated (CD62L-CD45RA+; CD95+CD28-) CD4+ and CD8+ T-cells were measured by flow cytometry.

Results

Of the 107 participants included in the analysis, 14% were CMV+ viremic; 49% CMV+ aviremic; 37% CMV-naïve. In longitudinal adjusted models, compared with CMV+ status, baseline CMV-naïve status was significantly associated with faster recovery of CD8+CD62L+CD45RA+% and CD8+CD95-CD28+% and faster decrease of CD8+CD95+CD28-%, independent of HIV VL response to treatment, cART regimen and baseline CD4%. Surprisingly, CMV status did not have a significant impact on longitudinal trends in CD8+CD38+HLA-DR+%. CMV status did not have a significant impact on any CD4+ T-cell subsets.

Conclusions

In this cohort of PHIV+ children, the normalization of naïve and terminally differentiated CD8+ T-cell subsets in response to cART was detrimentally affected by the presence of CMV co-infection. These findings may have implications for adjunctive treatment strategies targeting CMV co-infection in PHIV+ children, especially those that are now adults or reaching young adulthood and may have accelerated immunologic aging, increased opportunistic infections and aging diseases of the immune system.  相似文献   

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