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101.
Using differential radiation sensitivity of components of mouse embryonal thymus, an in vitro method for studying T-cell differentiation from hemopoietic stem cells (HSCs) in the G0 phase was established. Intrathymic T-cell precursors present in embryonal thymus were found to be quite radioresistant (up to 20 Gy), and consequently 25-Gy-irradiated embryonal thymic lobes were used. Thymic lobes (25-Gy irradiated) taken from mouse fetuses (gestation day 15) were placed in Millipore-HA culture plates supported on squares of gelatin foam sponge in 24-well culture plates in which neonatal thymus stromal cells were cultured. HSCs (10(5) cells per well) in the G0 phase were added to these thymic lobes and cocultured at 37 degrees C in a 5% CO2/95% air incubator. Half the culture medium was changed every week. After 3 weeks, a large number of colonies had formed. Immunohistochemical studies and fluorescence-activated cell sorter analyses revealed that the colonizing cells regularly develop and exhibit surface markers characteristic of T cells (Thy-1, IL-2R, L3T4, Lyt-2, etc.). In situ hybridization analyses revealed that mRNA expression for T-cell receptor (TCR) beta chains occurred within colonizing cells. Using a monoclonal antibody (F23.1), expression of TCR beta-chain variable domain (V beta 8) on the surface of these developing T cells was demonstrated. These cells responded to interleukin 2 and/or anti-CD3 monoclonal antibody, indicating functional T cells. This method will be useful in studying T-cell differentiation pathways from pluripotent HSCs and in clarifying the mechanisms involved in negative and positive selection of T cells within the thymus.  相似文献   
102.
Innes AM, Boycott KM, Puffenberger EG, Redl D, MacDonald IM, Chudley AE, Beaulieu C, Perrier R, Gillan T, Wade A, Parboosingh JS. A founder mutation in BBS2 is responsible for Bardet‐Biedl syndrome in the Hutterite population: utility of SNP arrays in genetically heterogeneous disorders. Bardet‐Biedl syndrome (BBS) is a multisystem genetically heterogeneous disorder, the clinical features of which are largely the consequence of ciliary dysfunction. BBS is typically inherited in an autosomal recessive fashion, and mutations in at least 14 genes have been identified. Here, we report the identification of a founder mutation in the BBS2 gene as the cause for the increased incidence of this developmental disorder in the Hutterite population. To ascertain the Hutterite BBS locus, we performed a genome‐wide single nucleotide polymorphism (SNP) analysis on a single patient and his three unaffected siblings from a Hutterite family. The analysis identified two large SNP blocks that were homozygous in the patient but not in his unaffected siblings, one of these regions contained the BBS2 gene. Sequence analysis and subsequent RNA studies identified and confirmed a novel splice site mutation, c.472‐2A>G, in BBS2. This mutation was also found in homozygous form in three subsequently studied Hutterite BBS patients from two different leuts, confirming that this is a founder mutation in the Hutterite population. Further studies are required to determine the frequency of this mutation and its role, if any, in the expression of other ciliopathies in this population.  相似文献   
103.
People are living longer and healthier with HIV infection because of successful combination antiretroviral therapies. HIV treatment beliefs are often associated with sexual practices among people living with HIV/AIDS but these associations may depend on the HIV status of sex partners. In a sample of 158 HIV positive men and women who were receiving HIV treatments, we examined the association between HIV treatment beliefs, HIV transmission risk perceptions, medication adherence, viral load and engaging in unprotected intercourse with any sex partners and specifically with sex partners who were not HIV positive (non-concordant). Results showed having missed medications in the past two days and treatment-related beliefs were significantly associated with engaging in unprotected intercourse with all sex partners as well as non-concordant partners. However, multivariate models showed that only treatment beliefs were significantly associated with engaging in unprotected intercourse with non-concordant partners. These results extend past research by demonstrating that the HIV status of sex partners sets the context for whether prevention-related treatment beliefs are associated with HIV transmission risk behaviors among people living with HIV/AIDS.  相似文献   
104.
High-dose therapy (HDT) and autologous hematopoietic cell transplantation (auto-HCT) has been anecdotally prescribed in gray zone lymphoma (GZL), showing encouraging efficacy. We conducted a multicenter retrospective study aimed at assessing outcomes after auto-HCT in 32 patients with GZL treated at 9 transplantation centers in the United States. The median age of patients at transplantation was 38 years (range, 18 to 70 years), and the majority were male (n?=?21; 66%). The median number of lines of therapy before transplantation was 2 (range, 1 to 4). BEAM was the most commonly prescribed regimen (n?=?23; 72%). The median duration of follow-up for surviving patients was 34 months (range, 1 to 106 months). Median overall survival (OS) was not reached. The 3-year progression-free survival (PFS) and OS for all patients were 69% and 78%, respectively. Three-year PFS and OS were 100% for patients who received only 1 line of therapy before auto-HCT versus 65% (PFS, P?=?.25) and 75% (OS, P?=?.39) for those receiving >1 line. The cumulative incidence of relapse/progression was 4% at 1 year post-transplantation and 31% at 3 years post-transplantation. The 3-year nonrelapse mortality was 0%. These findings suggest that HDT and auto-HCT is an effective treatment in patients with GZL. Our findings ideally require confirmation in a larger cohort of patients, preferably in the setting of large prospective multicenter randomized controlled trials. However, we acknowledge that such studies could be difficult to conduct in patients with GZL owing to the disease's rarity. Alternatively, a multicenter prospective study that includes tissue banking and a data registry is warranted to help better understand the biology and natural history of the disease.  相似文献   
105.

Objective

To investigate whether and how doctors’ attachment styles and emotional intelligence (EI) might influence patients’ emotional expressions in general practice consultations.

Methods

Video recordings of 26 junior doctors consulting with 173 patients were coded using the Verona Coding Definition of Emotional Sequences (VR-CoDES). Doctors’ attachment style was scored across two dimensions, avoidance and anxiety, using the Experiences in Close Relationships: Short Form questionnaire. EI was assessed with the Mayer-Salovey-Caruso Emotional Intelligence Test. Multilevel Poisson regressions modelled the probability of patients’ expressing emotional distress, considering doctors’ attachment styles and EI and demographic and contextual factors.

Results

Both attachment styles and EI were significantly associated with frequency of patients’ cues, with patient- and doctor-level explanatory variables accounting for 42% of the variance in patients’ cues. The relative contribution of attachment styles and EI varied depending on whether patients’ presenting complaints were physical or psychosocial in nature.

Conclusion

Doctors’ attachment styles and levels of EI are associated with patients’ emotional expressions in primary care consultations. Further research is needed to investigate how these two variables interact and influence provider responses and patient outcomes.

Practice implications

Understanding how doctors’ psychological characteristics influence PPC may help to optimise undergraduate and postgraduate medical education.  相似文献   
106.
Pharyngoesophageal diverticula (PED) of the Zenker's and Killian‐Jamieson types arise in close proximity to the thyroid gland, and may rarely be confused with a thyroid nodule on ultrasonography. In this brief report, we detail the cytologic, clinical, and radiologic findings of three PED that were thought to be thyroid nodules, and were subjected to fine‐needle aspiration (FNA). The patients were females with an age range of 51‐64 years. All three patients had multiple thyroid nodules, and two patients reported symptoms attributable to the diverticulum. Nodule sizes ranged from 1.0 to 2.7 cm, and either the right or left thyroid lobe could be involved. Microcalcifications were present by ultrasonography in all three cases. FNA of these thyroid nodule mimics showed squamous cells with granular or amorphous debris, bacterial and/or fungal colonies, inflammation, and food particles. These cytologic features, particularly the presence of vegetable or meat fragments, are characteristic, and have also been reported in the few previous reports of PED. The presence of a diverticulum was confirmed with imaging studies in all our patients. Although a rare occurrence, the inadvertent FNA of a PED masquerading as a thyroid nodule is important to recognize, as a recommendation for appropriate radiologic studies could potentially avoid inappropriate therapy for thyroid disease.  相似文献   
107.
Autosomal recessive nonsyndromic hearing impairment (ARNSHI) segregating in three unrelated, large consanguineous Pakistani families (PKDF528, PKDF859 and PKDF326) is linked to markers on chromosome 12q14.2-q15. This novel locus is designated DFNB74 . Maximum two-point limit of detection (LOD) scores of 5.6, 5.7 and 2.6 were estimated for markers D 12 S 313, D 12 S 83 and D 12 S 75 at θ = 0 for recessive deafness segregating in these three families. Haplotype analyses identified a critical linkage interval of 5.35 cM (5.36 Mb) defined by D 12 S 329 at 74.58 cM and D 12 S 313 at 79.93 cM. DFNB74 is the second ARNSHI locus mapped to chromosome 12, but the physical intervals do not overlap with one another. A locus contributing to the early onset, rapidly progressing hearing loss of A/J mice ( ahl4 , age-related hearing loss 4) was reported to map to chromosome 10 in a region of conserved synteny to DFNB74 , suggesting that ahl4 and DFNB74 may be due to mutations of the same gene in these two species.  相似文献   
108.
Medical information can improve health, and there is an enormous amount of health information available on the Internet. A randomized clinical trial tested the effectiveness of an intervention based on social- cognitive theory to improve information use among people living with HIV/AIDS. Men and women (N = 448) were placed in either (a) an 8-session intervention that focused on Internet information consumer skills or (b) a time-matched support group and were followed to 9 months postintervention. The Internet skills group demonstrated greater Internet use for health, information coping, and social support compared with the control group. The authors conclude that people with HIV infection may benefit from increased access to health information on the Internet and that vulnerability to misinformation and fraud can be reduced through behavioral interventions.  相似文献   
109.
In 2000, Teebi reported on a 4-year-old boy with a distinctive pattern of malformation, which he termed the "Nablus mask-like facial syndrome" (OMIM# 608156). Characterization of this syndrome has been difficult because of the paucity of patients described in the medical literature and its unknown etiology and pathogenesis. We present two patients with Nablus mask-like facial syndrome who both display a microdeletion in the 8q21-8q22 region detected by array-based comparative genomic hybridization. Patient 1, a boy, has a distinct facial appearance characterized by severe blepharophimosis, tight-appearing glistening facial skin, sparse and unruly hair, a flat and broad nose, and distinctive ears that are triangular in shape with prominent antihelices. He also demonstrates camptodactyly, contractures, unusual dentition, cryptorchidism, mild developmental delay, and a happy demeanor. Patient 2, a girl with a strikingly similar phenotype, was previously described in a report by Salpietro et al. 2003. She has distinctive ears, dental anomalies, and developmental delay. The etiology of her pattern of malformation was not identified at that time. Although high-resolution chromosome and subtelomeric FISH analyses were normal, array-based comparative genomic hybridization revealed an approximately 4 Mb deletion involving the 8q21.3-8q22.1 region in both patients. This region encompasses a number of genes that may contribute to this unique phenotype. These results demonstrate a chromosomal microdeletion as the etiology of Nablus mask-like facial syndrome and emphasize the diagnostic utility of array-based comparative genomic hybridization in the evaluation of multiple malformation syndromes of previously unrecognized causation.  相似文献   
110.
AIMS: To study the prevalence of disordered eating attitudes and behaviours among adolescents in Hong Kong and to examine the socio-demographic and behavioural correlates. METHODS: Three secondary schools with different academic performance were selected from the Eastern District of Hong Kong. A total of 2382 students enrolled in Forms 1-7 at the three schools completed a specially designed questionnaire. The questionnaire contained questions on socio-demographic information, body weight satisfaction, exposure to mass media, health behaviours as well as the Eating Attitudes Test - 26 (EAT-26). Data were analysed using Student's t-test, chi2 analysis and multivariate logistic regression models. RESULTS: Disordered eating (EAT score > or =20) was present in 52 (3.9%) adolescent boys and 68 (6.5%) adolescent girls. The youngest case was only 11 years old. A high degree of body weight dissatisfaction was shared by our adolescents. Teenage girls, overweight youths and those with poor academic performance were at increased risk of having disordered eating. Strong associations were found between disordered eating and other health-compromising behaviours including smoking, alcohol and soft drug use, delinquent behaviours, suicidal ideation and self-harm behaviours. Exposure to entertainment, beauty and youth magazines was positively related to disordered eating. CONCLUSIONS: Disordered eating is prevalent among adolescents in Hong Kong. It remains a significant public health challenge to our community. Prevention programmes targeting youths at the greatest risk should be considered.  相似文献   
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