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91.
Binding of mammalian spermatozoa to the zona pellucida and the induction of the acrosome reaction are prerequisites for successful oocyte fertilization. It has been postulated that xenobiotics that are released in the environment as well as exposure to pharmaceutical medications may be associated with reproductive problems in men and wildlife. Examining physiological and non-physiological effects of particular compounds on sperm functions requires high quality in-vitro test systems. We established a reliable combined in-vitro test system with bovine gametes and evaluated if aliquots of pooled post-thaw spermatozoa are suitable for examining essential sperm functions. Using cryopreserved semen, the PSA-FITC/Hoechst 33258 staining procedure was applicable to evaluate the acrosomal status and cell viability. In the bovine hemizona assay, hemizona indices revealed no differences between cryopreserved and fresh semen. Treatment of post-thaw bovine spermatozoa with progesterone (1 microM or bovine follicular fluid (20%) induced the acrosome reaction from 12% (untreated spermatozoa) to 25% (P < 0.001) and to 22% [corrected] (P < 0.01), respectively. Incubation of both compounds (1 microM progesterone and 20% follicular fluid) raised the percentage of acrosome-reacted spermatozoa to 30% (P < 0001). Our results demonstrate that cryopreserved semen can be integrated into an in-vitro screening model for reproductive toxicology testing. Pooled, cryopreserved bovine spermatozoa will thus permit reproducible experiments for clinical and basic science purposes and may also be applicable for the human system.   相似文献   
92.
93.
We have successfully cloned nine NKR-P1+ TCR alpha beta + cells from PVG rat spleens, utilizing murine macrophage inflammatory protein-1 alpha (MIP-1 alpha) and IL-2. These clones are either double negative (DN, CD4-CD8-), which included clones 3.31, 3.71, 4.19, 4.59 and 4.65, or single positive (SP, CD4+CD8-), which included clones 1.64, 3.8, 3.76 and 3.78. No CD8+ clone was recovered. All nine clones are restricted in terms of their expression of the V beta antigens, since they express V beta 8.2 but not V beta 8.5, V beta 10 or V beta 16. These clones are agranular and they fall to generate NK or LAK activity upon incubation with IL-2, IL-12 or their combination. On the basis of their production of intracellular cytokines they can be divided into three categories: (I) SP clones (1.64, 3.8, 3.76 and 3.78) do not produce IL-2 or IL-4, but produce IFN-gamma and IL-12, and they vary in their production of IL-1, RANTES or tumor necrosis factor (TNF)-alpha; (II) DN clones 4.59 and 4.65 produce IL-1 alpha and IFN-gamma only, and fall to produce other cytokines; and (III) DN clones 3.31, 3.71 and 4.19 produce IL-1 alpha, IL-1 beta, IL-2, IL-12, IFN-gamma, RANTES and TNF-alpha. From all the clones examined only DN clones 3.31 and to a lesser degree 4.19 produce IL-4. In vivo tissue localization of clones 3.8, 3.31 and 4.59 shows that these cells distribute into the liver and bone marrow 24 h post i.v. administration. Their accumulation in the liver and bone marrow along with their ability to secrete various cytokines suggest that these cells may influence the generation, differentiation or apoptosis of immune or hematopoietic cells.   相似文献   
94.
95.
BACKGROUND: An increasing number of apheresis machines are becoming available for peripheral blood progenitor cell (PBPC) collection in children. STUDY DESIGN AND METHODS: At the Children's Hospital of Florence (Italy), three apheresis machines were evaluated: MCS 3P (Haemonetics) (10 procedures in 4 patients, aged 10–12 years, weight 23.5-64 kg), Spectra, (COBE) (8 procedures in 3 patients, aged 4–17 years, weight 19–59 kg), and AS104 (Fresenius) (24 procedures in 9 patients, aged 2–16 years, weight 13.6-60 kg). For PBPC quantitative analysis, CD34 cytofluorimetry was employed. Relevant variables analyzed included efficiency of CD34+ cell extraction and enrichment, mononuclear cell purity and red cell contamination of the apheresis components, and platelet count decreases after leukapheresis. RESULTS: No significant differences in CD34+ cell-extraction abilities were found. However, the AS104 provided consistently purer leukapheresis components in terms of mononuclear cell and CD34+ cell enrichment (441 +/− 59%, vs. 240 +/− 35% and 290 +/− 42% for MCS 3P and Spectra, respectively). Postapheresis platelet counts dropped the least with the AS104. The smallest patient who underwent apheresis with MCS 3P (the only machine working on discontinuous flow and hence with greater volume shifts) weighed 23.5 kg and tolerated the procedure well, with no signs of hemodynamic instability. No significant complications were observed. CONCLUSION: All machines seem to have comparable PBPC extraction efficiency, but the AS104 seems to give the component with the greatest PBPC enrichment. This feature might be relevant for further ex vivo cell processing (CD34+ cell selection, expansion, and so on).  相似文献   
96.
BACKGROUND: Dysmenorrhea is the most common menstrual complaint in young women, with a prevalence as high as 90%. It is responsible for substantial repeated short-term absenteeism from school and work in young women. Effective treatments are available, including nonsteroidal anti-inflammatory drugs (NSAIDs). In many countries, a variety of NSAIDs have become available as over-the-counter (OTC) drugs. OBJECTIVE: The goal of this study was to compare the efficacy and safety of OTC doses of naproxen (400 mg) and naproxen/naproxen sodium (200/220 mg) with acetaminophen (1000 mg), ibuprofen (200 mg), and placebo in the treatment of primary dysmenorrhea. METHODS: A pooled analysis of 5 trials was performed. Efficacy was assessed by pain relief, relief of other dysmenorrheic symptoms, time to backup medication or remedication, and treatment preference. Tolerability was assessed by recording adverse events (AEs). RESULTS: A total of 443 women were enrolled in the combined studies. Naproxen 400 mg provided greater pain relief than acetaminophen and placebo within 30 minutes of administration (P < 0.01 and P < 0.05, respectively). Furthermore, naproxen 400 mg and 200 mg provided greater pain relief than both acetaminophen (P < 0.01 and P < 0.05, respectively) and ibuprofen (P < 0.001 and P < 0.01, respectively) at 6 hours after administration. Both doses of naproxen had higher scores than placebo for symptom relief and drug preference (all P < 0.001). The AEs and their frequency were similar among the treatment groups. No serious AEs were reported. CONCLUSION: When administered at OTC doses, naproxen was effective in the relief of pain and other symptoms of primary dysmenorrhea and had a good safety profile in the population studied.  相似文献   
97.
Bartelmez  SH; Dodge  WH; Mahmoud  AA; Bass  DA 《Blood》1980,56(4):706-711
Eosinophilopoietin (EPP) was previously characterized by the ability to stimulate eosinophil production in vivo, but these studies could not ascertain whether EPP had a direct effect on the bone marrow or acted indirectly by causing release of eosinophilopoietic activity by other tissues. The present studies demonstrate that EPP stimulates eosinophil growth in liquid culture of mouse bone marrow in vitro. The timing of stimulation by EPP in vivo and in vitro were parallel, with maximal eosinophil growth after 48 hr. Moreover, EPP appears similar to, and possible identical with, the eosinophil growth-stimulating substance (EO-GSF) released by antigenic stimulation of immune nonadherent spleen cells. Both EPP and EO-GSF are of low molecular weight, both produce stimulation of eosinophil growth with identical kinetics, and both produced similar dose-response curves in the liquid culture system.  相似文献   
98.
Although peripheral blood stem cell collections (PBSC) are thought to have less tumor involvement than bone marrow (BM), the incidence of circulating tumor cells in patients with breast cancer has not been widely investigated. We prospectively investigated the incidence and viability of tumor cell involvement in PBSC and BM collections from breast cancer patients undergoing high-dose chemotherapy/hematopoietic stem cell transplantation. Paired samples of PBSC and BM from 48 patients were analyzed using an immunocytochemical technique that detects one epithelial-derived tumor cell per 5 x 10(5) mononuclear cells. Immunostained tumor cells were detected in 9.8% (13/133) PBSC specimens from 9/48 (18.7%) patients and in 62.3% (38/61) BM specimens from 32/48 (66.7%) patients, a significantly higher rate than in PBSC (P < .005). The geometric mean concentration of tumor cells in contaminated PBSC specimens was 0.8/10(5) mononuclear cells (range 0.33 to 2.0/10(5)) compared with 22.9/10(5) mononuclear cells in BM (range 1 to 3,000/10(5), P < .0001). In culture experiments, clonogenic tumor colonies grew in 21/26 immunocytochemically positive specimens. No tumor colony growth was detected in 30/32 immunocytochemically negative specimens. Immunocytochemical detection of tumor involvement in BM and PBSC correlated significantly with in vitro clonogenic growth (P < .0001). We conclude that PBSC contain fewer tumor cells than paired BM specimens from patients with advanced breast cancer and that these tumor cells appear to be capable of clonogenic growth in vitro.  相似文献   
99.
100.
Thalassaemia is a public health problem in Malaysia, with each ethnic group having their own common mutations. However, there is a lack on data on the prevalence and common mutations among the indigenous people. This cross‐sectional study was performed to determine the common mutations of α‐ and β‐thalassaemia among the subethnic groups of Senoi, the largest Orang Asli group in Peninsular Malaysia. Blood samples collected from six Senoi subethnic groups were analysed for full blood count and haemoglobin analysis (HbAn). Samples with abnormal findings were then screened for α‐ and β‐globin gene mutations. Out of the 752 samples collected, 255 showed abnormal HbAn results, and 122 cases showing abnormal red cell indices with normal HbAn findings were subjected to molecular screening. DNA analysis revealed a mixture of α‐ and β‐globin gene mutations with 25 concomitant cases. The types of gene abnormalities detected for α‐thalassaemia were termination codon (T>C) Hb CS (αCSα), Cd59 (G>A) haemoglobin Adana (Hb Adana) (αCd59α), initiation codon (ATG>A‐G) (αIniCdα), two‐gene deletion (SEA), and single‐gene 3.7‐kb deletion (‐α3.7). For β‐thalassaemia, there were Cd26 (G>A) Hb E (βE), Cd19 (A>G) Haemoglobin Malay (Hb Malay) (βCd19), and IVS 1–5 (G>C) (βIVS 1–5).  相似文献   
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