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51.

Purpose

To perform Preimplantation Genetic Diagnosis (PGD) on a paternal Brca2 unknown mutation carrier with early-onset breast cancer, whose paternal grandmother and mother had breast cancer at 60s.

Method

Elucidating the linkage via single sperm haplotyping on patient''s carrier brother, and identifying the genomic deletion via BLAST followed by PCR screening. PGD was subsequently conducted.

Result

The mutant allele was found by using 4 microsatellite and 2 intragenic SNP markers. Recombination was detected in 8 % of sperms. BLAST was utilized to locate putative hairpin structure(s), followed by PCR screening with seven sets of primers. A novel 2,596 bp deletion containing exon 15 ~ 16 was identified. Due to the severity of phenotype and the integrity of exon 11 encoding RAD51 binding domain, and the fact that the patient''s mother also had breast cancer at her 60s, we speculate a possible coexistence of maternal breast cancer risk allele(s). Embryo biopsy was performed on day 3. Unaffected morula and blastocyst were replaced on day 5, resulting in a singleton livebirth. A breast lump appeared in the patient after delivery without the presence of malignant cells.

Conclusion

Concerning the assisted reproductive option for breast cancer patients, the possibility of coexistence of multiple familial risk alleles and the significance of each mutation to the phenotype should be evaluated. To eliminate misdiagnosis resulting from recombination and/or allelic drop-out, both direct mutation detection and linkage analysis approaches may be necessary. BLAST is a very useful and cost-effective tool for identifying large genomic deletion.  相似文献   
52.
Following the total removal of luteal tissue, circulating plasma progesterone, intrauterine pressure, oxytocin response, and clinical progress in abortion were determined sequentially in 12 first-trimester pregnant patients. 3 patients were ovariectomized for the removal of ovarian cysts and 9 were luteectomized during tubal ligation in an attempt to terminate pregnancy in spontaneous abortion. 7 patients had corpora lutea which averaged 21 plus or minus 1mm in diameter at operation when performed at Day 49 plus or minus 2 (mean S.E.) of pregnancy. These patients responded to ovariectomy or luteectomy by a continuing decrease in progesterone, evolution in intrauterine pressure, oxytocin response, progress in cervical dilitation and, abortion. Abortion occurred with a mean lapse time of 5 plus or minus 1 days after operation. In contrast, 5 patients whose corpora lutea averaged only 11 plus or minus 1mm in diameter when removed at Day 61 plus or minus 4 of pregnancy showed only transient decrease in progesterone after operation. This decrease was followed by an increase in progesterone; no progress in the evolution of intrauterine pressure, oxytocin response, cervical dilatation, and abortion. It appears that so long as the corpus luteum serves as the major source of progesterone, it is indispensable in the maintenance of pregnancy in human subjects as it is in the clinical model animal, the rabbit. However, with the shift of progesterone production from the corpus luteum to the placenta (the luteoplacental shift) the human corpus luteum becomes dispensable. These findings identify the corpus luteum and its secretory product, progesterone, as feasible targets of fertility control strategy.  相似文献   
53.

Background

Injection drug use (IDU) is a primary vector for blood-borne infections. Awareness of Hepatitis C virus (HCV) infection status may affect risky injection behaviors. This study determines the prevalence of risky injection practices and examines associations between awareness of positive HCV status and risky injection behaviors.

Methods

We surveyed individuals seeking treatment for substance use at 12 community treatment programs as part of a national HIV screening trial conducted within the National Drug Abuse Treatment Clinical Trials Network. Participants reported socio-demographic characteristics, substance use, risk behaviors, and HCV status. We used multivariable logistic regression to test associations between participant characteristics and syringe/needle sharing.

Results

The 1281 participants included 244 (19.0%) individuals who reported injecting drugs in the past 6 months and 37.7% of IDUs reported being HCV positive. During the six months preceding baseline assessment, the majority of IDUs reported obtaining sterile syringes from pharmacies (51.6%) or syringe exchange programs (25.0%), but fewer than half of IDUs always used a sterile syringe (46.9%). More than one-third (38.5%) shared syringe/needles with another injector in the past 6 months. Awareness of positive HCV vs. negative/unknown status was associated with increased recent syringe/needle sharing (aOR 2.37, 95% CI 1.15, 4.88) in multivariable analysis.

Conclusions

Risky injection behaviors remain prevalent and awareness of HCV infection was associated with increased risky injection behaviors. New approaches are needed to broadly implement HCV prevention interventions for IDUs seeking addiction treatment.  相似文献   
54.
CT scanning: patterns of use and dose.   总被引:19,自引:0,他引:19  
CT scanning is a relatively high-dose procedure. In spite of the use of magnetic resonance imaging, with faster CT scanners and helical techniques CT is becoming more common. There are few data from practice in the United States regarding the age and sex distribution of patients receiving CT scans, what type of scan and how many scans they receive, or how much radiation dose CT scans contribute. We reviewed over 33,700 consecutive CT examinations done at our institution in 1998 and 1999. Information on the types of scans as well as the age and sex distribution of the patients was determined. Between 1990 and 1999, CT examinations in our institution increased from 6.1% to 11.1% of all radiology procedures. Nineteen per cent of all patients seen in our department in the last year had at least one CT scan and more than half had multiple scans on the same day. Thirty-six per cent of all patients had a prior CT examination done on an earlier date. The male/female ratio of patients was 56/44. Studies of children age 0-15 years comprised 11.2% of scans. The highest percentage of scans was done in the 36-50-year-old age group. CT scanning accounted for 67% of the effective dose from diagnostic radiology. In most large hospitals in the United States CT scanning probably accounts for more than 10% of diagnostic radiology examinations and about two-thirds of the radiation dose. Most patients have multiple scan sequences. Studies done on children are probably more common than previously thought.  相似文献   
55.
从绵毛马兜铃(Aristolocha mannisima Hance)中分得一个马兜铃酸倍半萜的酯类化合物,经红外、紫外、高分辩质谱和多种一维和二维核磁共振谱鉴定,确定了其骨架结构及顺反构型,命名为马兜铃酸萜酯I。  相似文献   
56.
Histone deacetylase 1 (HDAC1) has been linked to cell growth and cell cycle regulation, which makes it a widely recognized target for anticancer drugs. Whereas variations of the metal-binding and capping groups of HDAC inhibitors have been studied extensively, the role of the linker region is less well known, despite the potency of inhibitors with diverse linkers, such as MS-275. To facilitate a drug design that targets HDAC1, we assessed the influence of residues in the 11 A channel of the HDAC1 active site on activity by using an alanine scan. The mutation of eight channel residues to alanine resulted in a substantial reduction in deacetylase activity. Molecular dynamics simulations indicated that alanine mutation results in significant movement of the active-site channel, which suggests that channel residues promote HDAC1 activity by influencing substrate interactions. With little characterization of HDAC1 available, the combined experimental and computational results define the active-site residues of HDAC1 that are critical for substrate/inhibitor binding and provide important insight into drug design.  相似文献   
57.
The neonatal ventral hippocampal lesion (NVHL) manipulation is a neurodevelopmental animal model of schizophrenia that produces abnormalities in the prefrontal cortex and nucleus accumbens, both efferent targets of the hippocampus, and leads to spatial working memory impairments. To investigate the neuroanatomical basis of spatial working memory in NVHL animals, we assessed performance in two radial arm maze tasks known to be differentially sensitive to the two hippocampal efferent pathways, and measured levels of neuronal activation (Fos immunoreactivity [Fos-IR]) in the prefrontal cortex and nucleus accumbens following task performance. Neonatal rats (postnatal day 6–8) received excitotoxic lesions of the ventral hippocampus (n = 25), or a sham procedure (infusions of artificial cerebrospinal fluid; n = 22). Upon reaching adulthood, animals were trained in either a non-delayed random foraging task or a spatial delayed win-shift task. NVHL animals were impaired on the spatial delayed win-shift task, which depends on communication between hippocampus and prefrontal cortex, but were unimpaired on the non-delayed random foraging task, which requires connections between hippocampus and nucleus accumbens. Fos-IR in the nucleus accumbens was greater in NVHL animals than in shams following the random foraging task, despite similar levels of performance, while no group differences in Fos-IR in either the nucleus accumbens or prefrontal cortex were observed following win-shift performance. These results suggest that although the NVHL manipulation disrupts development of hippocampal efferents to both the prefrontal cortex and the nucleus accumbens, the disruption of hippocampal–prefrontal pathways has the dominant behavioral effect on spatial performance in NVHL rats.  相似文献   
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