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21.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献
22.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献
23.
Induction of a differentiated ciliated cell phenotype in primary cultures of Fallopian tube epithelium 总被引:5,自引:1,他引:5
Human Fallopian tubal epithelial cells in culture lose morphological
features associated with the epithelium in situ and the extent to which
they retain their in-vivo phenotype or function is unknown. In order to
address this question, immunocytochemical markers were identified which
distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+)
epithelial cells in tissue sections of Fallopian tube. These markers were
used to analyse the phenotype of tubal cells in vitro. Primary cultures of
human tubal epithelial cells were seeded onto glass and grown to confluence
before addition of oestradiol-17beta. In the absence of hormone, tubal
epithelial cells expressed cytokeratins and nuclear receptors for oestrogen
and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell
phenotype. Following the addition of oestradiol-17beta, a proportion of
cells became positive for LhS28. The induction of a ciliated epithelial
cell phenotype was confirmed by scanning electron microscopy, where on
permeable collagen membranes, approximately one-third of tubal epithelial
cells became ciliated in the presence of oestradiol-17beta. We suggest that
in vitro, tubal epithelial cells adopt an immature secretory-like phenotype
and that oestrogen can induce differentiation to a ciliated epithelial cell
phenotype.
相似文献
24.
Peer Arts Jessica Garland Alicia B. Byrne Tristan S.E. Hardy Milena Babic Jinghua Feng Paul Wang Thuong Ha Sarah L. King‐Smith Andreas W. Schreiber April Crawford Nick Manton Lynette Moore Christopher P. Barnett Hamish S. Scott 《American journal of medical genetics. Part A》2020,182(5):1273-1277
Autosomal dominant (de novo) mutations in PBX1 are known to cause congenital abnormalities of the kidney and urinary tract (CAKUT), with or without extra‐renal abnormalities. Using trio exome sequencing, we identified a PBX1 p.(Arg107Trp) mutation in a deceased one‐day‐old neonate presenting with CAKUT, asplenia, and severe bilateral diaphragmatic thinning and eventration. Further investigation by droplet digital PCR revealed that the mutation had occurred post‐zygotically in the father, with different variant allele frequencies of the mosaic PBX1 mutation in blood (10%) and sperm (20%). Interestingly, the father had subclinical hydronephrosis in childhood. With an expected recurrence risk of one in five, chorionic villus sampling and prenatal diagnosis for the PBX1 mutation identified recurrence in a subsequent pregnancy. The family opted to continue the pregnancy and the second affected sibling was stillborn at 35 weeks, presenting with similar severe bilateral diaphragmatic eventration, microsplenia, and complete sex reversal (46, XY female). This study highlights the importance of follow‐up studies for presumed de novo and low‐level mosaic variants and broadens the phenotypic spectrum of developmental abnormalities caused by PBX1 mutations. 相似文献
25.
Macrophage-lymphocyte association in in vitro mouse spleen cultures; the formation of B-cell colonies. 下载免费PDF全文
Colonies of predominantly B lymphocytes have been grown in liquid culture, without agar or specific mitogen treatment. An essential component of the colonies is a macrophage-like cell. Colonies appear to result from continued growth of B lymphocytes following a primary macrophage-lymphocyte association which frequently occurs under a variety of culture conditions. Factors promoting colony growth are foetal calf serum and 2 mercapto-ethanol, the latter acting in part through reduction of a non-dialysable sulphur-containing component of serum. 相似文献
26.
Desensitization in the process of histamine secretion induced by antigen and dextran 总被引:8,自引:1,他引:8 下载免费PDF全文
1. Antigen challenge of sensitized rat peritoneal mast cells in the absence of calcium failed to release histamine. The release when calcium was added subsequently declined rapidly, this desensitization being almost complete in 4 min.2. Phosphatidyl serine (10 mug/ml.) reduced the rate of desensitization so that decay of the response to added calcium was not complete after 16 min.3. Exposing normal cells to dextran resulted in a slow rate of desensitization, the response to phosphatidyl serine added with calcium having decayed by only 27% within 10 min.4. Phosphatidyl serine added with dextran prevented desensitization so that the response to subsequently added calcium did not decay even after an interval of 20 min.5. Cells activated by dextran and calcium became rapidly desensitized as shown by decay of the response to added phosphatidyl serine which was almost complete by 5 min.6. Histamine release by the calcium ionophore (A 23187) added to cells at intervals before the addition of calcium did not show significant decay.7. Desensitization of the cells to antigen did not change their response to the ionophore. 相似文献
27.
Carolina Tisnado Garland Line Guénette Edeltraut Kröger Pierre-Hugues Carmichael Rachel Rouleau Caroline Sirois 《Journal of the American Medical Directors Association》2021,22(1):141-147
ObjectivesAssess the impact of a new pharmaceutical care model on (1) polypharmacy and (2) potentially inappropriate medication (PIM) use in long-term care facilities (LTCFs).DesignPragmatic quasi-experimental study with a control group. This multifaceted model enables pharmacists and nurses to increase their professional autonomy by enforcing laws designed to expand their scope of practice. It also involves a strategic reorganization of care, interdisciplinary training, and systematic medication reviews.Setting and ParticipantsTwo LTCFs exposed to the model (409 residents) were compared to 2 control LTCFs (282 residents) in Quebec, Canada. All individuals were aged 65 years or older and residing in included LTCFs.MeasuresPolypharmacy (≥10 medications) and PIM (2015 Beers criteria) were analyzed throughout 12 months between March 2017 and June 2018. Groups were compared before and after implementation using repeated measures mixed Poisson or logistic regression models, adjusting for potential confounding variables.ResultsOver 12 months, for regular medications, polypharmacy decreased from 42% to 20% (exposed group) and from 50% to 41% (control group) [difference in differences (DID): 13%, P < .001]. Mean number of PIMs also decreased from 0.79 to 0.56 (exposed group) and from 1.08 to 0.90 (control group) (DID: 0.05, P = .002).Conclusions and ImplicationsCompared with usual care, this multifaceted model reduced the probability of receiving ≥10 medications and the mean number of PIMs. Greater professional autonomy, reorganization of care, training, and medication review can optimize pharmaceutical care. As the role of pharmacists is expanding in many countries, this model shows what could be achieved with increased professional autonomy of pharmacists and nurses in LTCFs. 相似文献
28.
Nursing home quality of care has been influenced by the Omnibus Budget Reconciliation Act of 1987. This legislation mandated changes within the structure, process, and outcomes of care. These care elements are examined from the viewpoints of 32 licensed nurses and 40 nurse assistants. Accounts of good care, obtained through focus groups, are presented within the context of structure, process, and outcome to understand quality care. Implications about training nursing personnel are considered within the structure and the process of care and how these elements affect care outcomes. 相似文献
29.
30.
Clinical pharmacology of oral all-trans retinoic acid in patients with acute promyelocytic leukemia. 总被引:14,自引:0,他引:14
J R Muindi S R Frankel C Huselton F DeGrazia W A Garland C W Young R P Warrell 《Cancer research》1992,52(8):2138-2142
All-trans retinoic acid (RA) induces leukemic cell differentiation and complete remission in a high proportion of patients with acute promyelocytic leukemia (APL). However, remissions induced by all-trans RA tend to be brief, and relapses are associated with resistance to further treatment in vivo, although the leukemic cells appear to retain sensitivity to the cytodifferentiating effects of all-trans RA in vitro. The clinical pharmacology of all-trans RA was examined in 13 patients with APL. The drug was administered at a constant dose of 45 mg/m2/day, given as a single dose on the first day of therapy and in two divided doses thereafter. Plasma and urinary concentrations of the parent drug and metabolites were quantitated by reverse-phase high-performance liquid chromatography and, where required, by a combination of normal-phase liquid chromatography/negative chemical ionization mass spectrometry. In patients with APL, basal levels of endogenous retinol and natural retinoids were within the normal range. Peak plasma levels of all-trans RA (347 +/- 266 ng/ml, mean +/- SD) were reached 1-2 h after drug ingestion and decayed in a monoexponential fashion with a half-life of 0.8 +/- 0.1 h. The only drug metabolite detected in plasma or urine was 4-oxo-all-trans RA (present in urine as the glucuronide conjugate). This metabolite accounted for less than 10% of the circulating drug in plasma, and its cumulative urinary excretion accounted for less than 1% of the administered dose. The drug was not found in cerebrospinal fluid. Continued oral administration of all-trans RA was associated with a significant decrease in both the plasma peak levels and the area under the concentration-time curve (P = 0.01 and 0.004, respectively) when measured after 2-6 weeks of treatment. We previously reported that a decrease in plasma area under the concentration-time curve was highly correlated with clinical relapse. Observations in a subset of patients in this study suggested that, in fact, the major decrease occurred early, within the first 7 days of treatment. These changes were associated with a 10-fold increase in urinary excretion of 4-oxo-all-trans RA glucuronide, suggesting that the accelerated clearance from plasma was associated with increased drug catabolism. The rapid disappearance may explain early relapse from remissions induced by all-trans RA; clinical "resistance" to all-trans RA may either wholly or in part result from an inability to sustain effective plasma concentrations of all-trans RA during continuous treatment.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献