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21.
BACKGROUND: Human parvovirus B19 (B19) polymerase chain reaction (PCR) is now a routine analysis and serves as a diagnostic marker as well as a complement or alternative to B19 serology. The clinical significance of a positive B19 DNA finding is however dependent on the type of tissue or body fluid analysed and of the immune status of the patient. OBJECTIVES: To analyse the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients. STUDY DESIGN: Parvovirus B19 DNA was analysed in paired bone marrow and serum samples by nested PCR technique. Serum was also analysed for B19-specific IgG and IgM antibodies and the results were compared with clinical and epidemiological data. RESULTS AND CONCLUSIONS: B19 IgG was found in 41 of 50 patients (82%) whereas none was B19 IgM positive. The serologic evaluation showed that none of the patients had acute B19 infection. However, B19 DNA was detected by PCR in 13 of 50 (26%) bone marrow samples from these patients indicating a high frequency of persistent infection compared with previous reports of patient groups and healthy controls. In the study, 22 patients had rheumatoid arthritis (RA) and 7 of these RA patients were B19 DNA positive in bone marrow. Rheumatoid factor was positive in 4 of the 7 B19 DNA positive RA patients as compared with Rheumatoid factor positivity in all of the 15 B19 DNA negative RA patients. Erosive arthritis in X-ray was less common in the B19 DNA positive group than in the B19 DNA negative group. A high frequency of parvovirus B19 DNA was thus detected in bone marrow samples in rheumatic patients. The clinical data does not support a direct association between B19 PCR positivity and rheumatic disease manifestation. Therefore, the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients must be interpreted with caution.  相似文献   
22.
Anomalies of both No. 3 chromosomes, of the t(3q?; 3q+) type can be observed in human malignancy as reported previously. It is our experience that this anomaly is found predominantly in myeloproliferative disorders, as a rather rare event, though occurring more frequently than similar exchanges between other homologous chromosomes. Previous claims about a relationship between this anomaly and thrombocytosis could not be confirmed, but the features found in a few patients indicate that further research should be undertaken to clarify this point.  相似文献   
23.
BACKGROUND: Personality structure obtained from the psychobiological Temperament and Character Inventory (TCI) was studied in relation to self-reported seasonal variations in mood and behavior measured by the Seasonal Pattern Assessment Questionnaire (SPAQ). METHODS: The subjects comprised 1761 adults (57.6% women) in the age range 35-85 years, enrolled in the Betula prospective random cohort study of Umea, Sweden. RESULTS: Personality profiles of subjects who reported the occurrence of a high degree of seasonal variation as such were associated with a combination of high self-transcendence (ST) and high persistence (PS), irrespective of the level of harm avoidance (HA). Subjects who reported feeling worst in winter were associated with high HA, irrespective of the levels of ST and PS. Also, subjects feeling worst in summer or experiencing overall problems with seasonal variation were associated with high HA in their personality profiles. Using the SPAQ criteria to define seasonal affective disorder (SAD) or subsyndromal SAD (S-SAD), subjects with these disorders often had combinations of high self-transcendence (ST) and high persistence (PS), but with different associations with HA. LIMITATIONS: No evaluations were made for SAD or subsyndromal SAD according to the DSM-IV or ICD 10 criteria. CONCLUSIONS: Our results relating SPAQ with TCI give support for a dual vulnerability hypothesis for seasonal depression proposed in the literature, where it is attributed to a combination of a seasonal factor and a depression factor. Examining the literature regarding the relationships between the different TCI scales and monoamine neurotransmitter functions, those relationships suggest that these two vulnerability factors for seasonal depression may be modulated by different neurotransmitter systems.  相似文献   
24.
Gaucher's disease is the most common lysosomal storage disorder. It was identified in 1882 by Phillipe Gaucher, a French dermatologist. However, it was not until 1965 that Gaucher disease was found to be due to a deficiency in the enzyme glucocerebrosidase (EC 3.2.1.45) which breaks down glucocerebroside, a cell membrane component. The deficiency in this enzyme leads to an accumulation of glucocerebroside within the lysosomes of macrophages throughout the body. Gaucher's disease is classified into three types: type 1 (non-neuronopathic), type 2 (acute neuronopathic), and type 3 (subacute neuronopathic). Of the three, type 1 is the most common, affecting one in 40,000-200,000 people and having a high prevalence among Ashkenazi Jews, affecting one in 450-1500. The signs and symptoms of type 1 disease demonstrate marked heterogeneity, from asymptomatic or mildly symptomatic, to severe disability with disfigurement and even death. Hepatosplenomegaly and thrombocytopenia are well documented. Less well-recognized are often insidious skeletal complications which affect the majority of type 1 patients and which are its most debilitating feature. In addition to clinical suspicion, some morphologic, hematologic and biochemical indicators can help establish the diagnosis. However, definitive diagnosis is only made by determining the catalytic activity of the lysosomal enzyme glucocerebrosidase. Confirmation of heterozygosity requires the use of molecular biotechnology methods. About 150 mutations of the glucocerebrosidase gene have been identified in patients with Gaucher's disease, some of which are predictive of phenotype. The history of treatment of Gaucher disease started with splenectomy and continued with bone marrow transplantation, before the recent introduction of safe and effective enzyme replacement therapy. In Croatia, nine patients with type 1 Gaucher's disease have been identified so far. Seven patients are on enzyme replacement therapy, and past results demonstrated significant improvement in all clinical symptoms, without development of any side effects. However, new treatments, such as substrate balance therapy and gene therapy, may become available within the next few years. The place, if any, that such therapies will have in the treatment of patients with Gaucher's disease will be dependent on the results of clinical studies currently in progress.  相似文献   
25.
26.
The intravenous and oral dose kinetics of propranolol were studied in the dog both in a fasted state and immediately after a meal consisting of 100 g of cooked beef liver. Fifty Ci of3H-propranolol was administered intravenously simultaneously with a 40-mg oral dose of unlabeled propranolol. Plasma3H-propranolol was measured by specific extraction and liquid scintillation spectrometry, and unlabeled plasma propranolol was determined by gas chromatography-mass spectrometry. Feeding significantly reduced (25%) the elimination half-life and increased (52%) the systemic clearance of intravenous propranolol. The increase in the systemic clearance of propranolol after feeding was mostly due to an increase (60%) in apparent hepatic blood flow, which appeared to remain elevated for 5–7 hr. The meal had no influence on the apparent volume of distribution or plasma binding. Feeding did not affect the area under the concentration-time curve of oral propranolol, but significantly delayed the rate of oral propranolol absorption, shifting the time to reach peak plasma levels from 60 to 158 min. The results of this study suggest that feeding alters the disposition of propranolol in the dog by producing a sustained increase in hepatic blood flow.This work was supported by National Institute of Health grants GM 07534, GM 20387, and HL 29566.  相似文献   
27.
Lipid peroxidation aldehydes of the 4-hydroxy-, ß-unsaturatedtype, as well as the tobacco-smoke related , ß-unsaturatedaldehyde, acrolein, were highly cytotoxic and decreased theintracellular thiol content in cultured human bronchial fibroblastsafter treatment with micromolar concentrations. In comparison,formaldehyde and acetaldehyde were less toxic and 100- to 300-foldhigher doses were required to affect cell survival or thiollevels. The unsaturated aldehydes also markedly inhibited theDNA repair enzyme O6-methylguanine-DNA methyltransferase knownto have a cysteine residue in its active site, but had no effecton the activity of uracil-DNA glycosylase. Our results indicatethat reactive aldehydes of either exogenous or endogenous originhave direct cytotoxic effects and may also make cells more susceptibleto other toxic chemicals due to an impairment in cellular defensemechanisms, e.g., DNA repair and detoxification by systems requiringglutathione.  相似文献   
28.
This study aimed to test the effect of a 7-day high-salt (HS) diet on autonomic nervous system (ANS) activity in young healthy individuals and modulation of ANS on microvascular endothelial function impairment. 47 young healthy individuals took 7-day low-salt (LS) diet (3.5 g salt/day) followed by 7-day high-salt (HS) diet (~14.7 g salt/day). ANS activity was assessed by 24-h urine catecholamine excretion and 5-min heart rate variability (HRV). Skin post-occlusive reactive hyperemia (PORH) and acetylcholine-induced dilation (AChID) were assessed by laser Doppler flowmetry (LDF). Separately, mental stress test (MST) at LS and HS condition was conducted, followed by immediate measurement of plasma metanephrines’ level, 5-min HRV and LDF microvascular reactivity. Noradrenaline, metanephrine and normetanephrine level, low-frequency (LF) HRV and PORH and AChID significantly decreased following HS compared to LS. MST at HS condition tended to increase HRV LF/HF ratio. Spectral analysis of PORH signal, and AChID measurement showed that MST did not significantly affect impaired endothelium-dependent vasodilation due to HS loading. In this case, 7-day HS diet suppressed sympathetic nervous system (SNS) activity, and attenuated microvascular reactivity in salt-resistant normotensive individuals. Suppression of SNS during HS loading represents a physiological response, rather than direct pathophysiological mechanism by which HS diet affects microvascular endothelial function in young healthy individuals.  相似文献   
29.
BackgroundIn the context of the opioid epidemic, a limited but growing body of literature has found state medical marijuana laws (MMLs) to be associated with lower levels of opioid prescribing. However, robust evidence linking state MMLs with individual-level opioid-related outcomes is lacking, particularly among women. This finding is especially true for pregnant and parenting women, who have been disproportionately affected by the opioid crisis.MethodsUsing data drawn from the 2002–2014 National Survey on Drug Use and Heath, the study uses a difference-in-differences estimation strategy to compare opioid-related outcomes (opioid misuse initiation, opioid misuse in the past month and past year, and opioid use disorder) among all women, pregnant women, and parenting women in states with and without MMLs (before and after implementation). The study also investigates the impact of MMLs on marijuana use and marijuana use disorder.ResultsThe findings indicate that MMLs were not associated with opioid misuse, opioid misuse initiation, or opioid use disorder among all women, pregnant women, and parenting women. These laws were, however, positively correlated with marijuana use and marijuana use disorder among all women and women with children. In addition, MMLs were associated with an increase in the frequency of opioid misuse for pregnant women and a decrease in the frequency of opioid misuse for parenting women.ConclusionsThis finding suggests that, although medical marijuana may be viewed by some as a substitute for opioid analgesics, MMLs may not be an effective policy tool to tackle the opioid epidemic among women, especially pregnant and parenting women.  相似文献   
30.
Generalized arterial calcification of infancy (GACI) is a rare disorder caused by ENPP1 or ABCC6 variants. GACI is characterized by low pyrophosphate, arterial calcification, and high mortality during the first year of life, but the natural course and possible differences between the causative genes remain unknown. In all, 247 individual records for patients with GACI (from birth to 58.3 years of age) across 19 countries were reviewed. Overall mortality was 54.7% (13.4% in utero or stillborn), with a 50.4% probability of death before the age of 6 months (critical period). Contrary to previous publications, we found that bisphosphonate treatment had no survival benefit based on a start-time matched analysis and inconclusive results when initiated within 2 weeks of birth. Despite a similar prevalence of GACI phenotypes between ENPP1 and ABCC6 deficiencies, including arterial calcification (77.2% and 89.5%, respectively), organ calcification (65.8% and 84.2%, respectively), and cardiovascular complications (58.4% and 78.9%, respectively), mortality was higher for ENPP1 versus ABCC6 variants (40.5% versus 10.5%, respectively; p = 0.0157). Higher prevalence of rickets was reported in 70.8% of surviving affected individuals with ENPP1 compared with that of ABCC6 (11.8%; p = 0.0001). Eleven affected individuals presenting with rickets and without a GACI diagnosis, termed autosomal recessive hypophosphatemic rickets type 2 (ARHR2), all had confirmed ENPP1 variants. Approximately 70% of these patients demonstrated evidence of ectopic calcification or complications similar to those seen in individuals with GACI, which shows that ARHR2 is not a distinct condition from GACI but represents part of the spectrum of ENPP1 deficiency. Overall, this study identified an early mortality risk in GACI patients despite attempts to treat with bisphosphonates, high prevalence of rickets almost exclusive to ENPP1 deficiency, and a spectrum of heterogenous calcification and multiple organ complications with both ENPP1 and ABCC6 variants, which suggests an overlapping pathology. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.  相似文献   
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