Factors affecting penetration of zona-free hamster ova

The sperm penetration assay is an expensive, time-consuming test to assess male fertility in vitro. Although some investigators are enthusiastic in its application, others feel that it is not sensitive or specific enough to be used as part of the routine infertility evaluation. Indeed, this bioassay is not a faithful reproduction of in vivo conditions. However, if the SPA is abnormal, it is unlikely that sperm will fertilize a human ovum in vivo. Conversely, a normal SPA does not guarantee successful in vivo fertilization. No bioassay can be absolute in its predictive value, but false-negative results must be kept to a minimum for this bioassay to be of any clinical significance. Each laboratory performing the SPA should optimize the assay for sensitivity, reproducibility, and minimization of false-negative results and then establish normal and abnormal ranges of its own. If the limitations of the SPA are kept in mind, and if we employ it very selectively, it may still be useful.     

Empty sella syndrome in childhood

The empty sella syndrome is common in middle-aged women, usually presenting with headache, and only occasionally associated with endocrine or visual abnormalities. It is rare in childhood. Childhood cases tend to present either with endocrine disturbances, visual symptoms, or with craniofacial syndromes. We present three cases of complete empty sella with childhood onset, each discovered unexpectedly during evaluation of endocrine or visual dysfunction.     

大鼠胸腺降黑素受体的鉴定及生物学特性

应用放射配体结合法证实大鼠胸腺内存在降黑素特异结合部位，该结合位点可以满足特异结合部位的基本条件：１．低结合容量；２．高亲和力；３．可饱和性；４．可逆性；５．对降黑素高度特异性。此外，该特异结合位点具昼夜节律；亚细胞分布的研究表明以细胞核含量最高，线粒体次之，并具有年龄依赖性降低，以出生时最高。     

Molecular cytogenetic characterization of nasopharyngeal carcinoma cell lines and xenografts by comparative genomic hybridization and spectral karyotyping

Nasopharyngeal carcinoma (NPC) cell lines and xenografts represent valuable models for functional and therapeutic studies on this common malignancy in Southeast Asia. The karyotypic information in most NPC cell lines and xenografts, however, remains largely unclear to date. We have characterized the chromosomal aberrations in six commonly used human NPC cell lines and xenografts using the molecular cytogenetic technique of comparative genomic hybridization (CGH). Genomic imbalances identified in cell lines were further correlated with structural abnormalities indicated from spectral karyotyping (SKY) analysis. CGH revealed consistent overrepresentations of 8q (six out of six cases) with a smallest overlapping region identified on 8q21.1q22. Other common gains included 7p (4/6 cases), 7q (4/6 cases), 12q (4/6), and 20q (4/6 cases), where minimal overlapping regions were suggested on 7p15p14, 7q11.2q21, and 12q22q24.1. Common losses were detected on 3p12p21 (4/6 cases) and 11q14qter (4/6 cases). Although SKY analysis on cell lines revealed predominantly unbalanced rearrangements, reciprocal translocations that involved chromosome 2 [i.e., t(1;2), t(2;3), and t(2;4)] were suggested. Furthermore, SKY examination illustrated additional breakpoints on a number of apparently balanced chromosomes. These breakpoints included 3p21, 3q26, 5q31, 6p21.1p25, 7p14p22, and 8q22. Our finding of regional gains and losses and breakpoints represents information that may contribute to NPC studies in vitro.     

Translation and psychometric validation of the traditional Chinese version of patient-reported outcomes measurement information system Pediatric-25 Profile version 2.0 (PROMIS-25) in Chinese Children with Cancer in Hong Kong

Quality of Life Research - To translate and cross-cultural validate the PROMIS Pediatric-25 Profile 2.0 (PROMIS-25) into traditional Chinese, and to investigate its psychometric properties in...     

Efficacy of intracytoplasmic sperm injection using intentionally cryopreserved epididymal spermatozoa

Microsurgical epididymal sperm aspiration was a great advancein the therapy of patients with non-recon-structable, obstructiveazoospermia, most notably congenital bilateral absence of thevas deferens. Using conventional in-vitro fertilization, pregnancieswere rarely achieved because the rate of oocyte fertilizationwas extremely poor. However, the use of retrieved spermatozoain conjunction with intracytoplasmic sperm injection (ICSI)has dramatically increased the likelihood of embryo formation.Typically, sperm and oocyte harvesting are performed simultaneously.We have investigated whether frozen-thawed spermatozoa workas well as fresh spermatozoa. When we had concluded from ourown population of patients (groups I and II) that they did,we adopted a policy of aspirating spermatozoa, primarily cryopreservingthem and using them for ICSI at a later date. We found the fertilizationrates of this latter cohort of patients (group III) to be excellent(37% per oocyte), and the ongoing pregnancy rate is quite satisfactory(40 % per couple, 29% per cycle). We offer this approach asan alternative to the traditional scheme because it markedlyeases the burden of partner scheduling on both the couple andthe clinicians involved. In addition, assurance of the availabilityof male partner spermatozoa can be attained prior to beginningovulation induction.