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1.
Twenty-eight newly delivered mothers with inadequate lactation volunteered for a placebo-controlled double-blind trial of sulpiride 50 mg thrice daily for four weeks. Treatment was allocated at random, and serum prolactin concentrations and breast-milk yields were measured before and serially during the trial. Of the 26 women who completed the trial, 14 had taken sulpiride and 12 the placebo. In the sulpiride-treatment group the mean maternal serum prolactin concentration rose from 49.0 +/- SE 3.6 micrograms/l to a maximum of 402.1 +/0 43.2 micrograms/l at two weeks; in the placebo-treated group, however, the concentration fell during the trial (from 84.7 +/- 24.0 micrograms/l to 47.8 +/- 8.6 micrograms/l). Mean breast-milk yields also increased in the sulpiride-treatment group (by an average of 212-265 ml) and fell in the women given placebo. Of the 14 infants in the sulpiride-treatment group, four did not need supplementary feeds during the trial; in the control group, however, all infants continued to require such feeds. Infants in the sulpiride-treatment group gained significantly more weight than did the controls (p less than 0.05). Three women taking sulpiride complained of mild side effects, but none occurred in the infants. These findings suggest that sulpiride is an effective treatment for inadequate lactation in the puerperium.  相似文献   
2.
The refief of primary dysmenorrhea by ketoprofen and indomethacin   总被引:1,自引:0,他引:1  
The prostaglandin biosynthesis inhibitors ketoprofen and indomethacin were compared in the treatment of primary dysmenorrhea in a double-blind, cross-over trial involving 23 patients. Each drug was used for 2-4 days during 3 consecutive menstruations in randomized order. Good or moderate overall relief was obtained in 60 of the 68 ketoprofen-treated menstruations (88%). A dysmenorrhea score, based on subjective estimations of 8 symptoms, similarly decreased from a mean (+/- S.E.M.) basal level of 9.6 +/- 0.6 to 3.6 +/- 0.3 during ketoprofen treatment and to 4.0 +/- 0.3 during indomethacin. Both drugs relieved pelvic and lower back pains and eliminated vomiting and diarrhea in 82-97% of the cycles whereas headache, fatigue and nervousness were less frequently alleviated (40-67%). Eighteen of the 23 women (78%) had been unable to work during the first day of menstruation, the rate of working days lost was reduced to 4% with ketoprofen and 9 with indomethacin. Mild side-effects occurred during 12 ketoprofen and 14 indomethacin therapies. Ketoprofen thus seems to be as effective and tolerable as indomethacin in the treatment of primary dysmenorrhea.  相似文献   
3.
CBS (cystathionine beta-synthase) domains are found in proteins from all kingdoms of life, and point mutations in these domains are responsible for a variety of hereditary diseases in humans; however, the functions of CBS domains are not well understood. In the present study, we cloned, expressed in Escherichia coli, and characterized a family II PPase (inorganic pyrophosphatase) from Moorella thermoacetica (mtCBS-PPase) that has a pair of tandem 60-amino-acid CBS domains within its N-terminal domain. Because mtCBS-PPase is a dimer and requires transition metal ions (Co2+ or Mn2+) for activity, it resembles common family II PPases, which lack CBS domains. The mtCBS-PPase, however, has lower activity than common family II PPases, is potently inhibited by ADP and AMP, and is activated up to 1.6-fold by ATP. Inhibition by AMP is competitive, whereas inhibition by ADP and activation by ATP are both of mixed types. The nucleotides are effective at nanomolar (ADP) or micromolar concentrations (AMP and ATP) and appear to compete for the same site on the enzyme. The nucleotide-binding affinities are thus 100-10000-fold higher than for other CBS-domain-containing proteins. Interestingly, genes encoding CBS-PPase occur most frequently in bacteria that have a membrane-bound H+-translocating PPase with a comparable PP(i)-hydrolysing activity. Our results suggest that soluble nucleotide-regulated PPases act as amplifiers of metabolism in bacteria by enhancing or suppressing ATP production and biosynthetic reactions at high and low [ATP]/([AMP]+[ADP]) ratios respectively.  相似文献   
4.

Background

Our previous study has shown that prenatal exposure to X-ray irradiation causes cerebral hypo-perfusion during the postnatal development of central nervous system (CNS). However, the source of the hypo-perfusion and its impact on the CNS development remains unclear. The present study developed an automatic analysis method to determine the mean red blood cell (RBC) speed through single microvessels imaged with two-photon microscopy in the cerebral cortex of rats prenatally exposed to X-ray irradiation (1.5 Gy).

Methodology/Principal Findings

We obtained a mean RBC speed (0.9±0.6 mm/sec) that ranged from 0.2 to 4.4 mm/sec from 121 vessels in the radiation-exposed rats, which was about 40% lower than that of normal rats that were not exposed. These results were then compared with the conventional method for monitoring microvascular perfusion using the arteriovenous transit time (AVTT) determined by tracking fluorescent markers. A significant increase in the AVTT was observed in the exposed rats (1.9±0.6 sec) as compared to the age-matched non-exposed rats (1.2±0.3 sec). The results indicate that parenchyma capillary blood velocity in the exposed rats was approximately 37% lower than in non-exposed rats.

Conclusions/Significance

The algorithm presented is simple and robust relative to monitoring individual RBC speeds, which is superior in terms of noise tolerance and computation time. The demonstrative results show that the method developed in this study for determining the mean RBC speed in the spatial frequency domain was consistent with the conventional transit time method.  相似文献   
5.
Biogenic structures in Holocene sediments from the Archipelago Sea, northern Baltic Sea, were characterized through the analysis of X-ray images of four cores collected from water depths between 32 and 66 m. In the area, initial colonization of endobenthic invertebrates occurred at 7800 ± 80 calendar years BP. The trace assemblage at this level is low-diversity, small-diameter, shallowly tiered, and Palaeophycus-dominated; rare Arenicolites are also observed. Early colonization coincides with increasing marine influence in the post-glacial lacustrine setting just before the dramatic onset of brackish-water conditions established after 7600 BP. The post-incursion brackish-water assemblage possesses a higher diversity of traces (Planolites, Arenicolites, Lockeia, Teichichnus), which is taken to reflect the enhanced salinity and trophic state of the basin. The shift from Palaeophycus-mottling to a Planolites-dominated fabric represents changed behavioural patterns in the endobenthic community due to changed substrate properties. The ethology of the succeeding trace assemblage also represents a switch from domicile-based activities, such as predation, scavenging and interface-dominated deposit feeding to shallow-tier deposit feeding. Finally, traces are excluded from thinly laminated intervals, demonstrating that seafloor oxygen deficiency commonly reached levels that were detrimental to colonization of the sediment substrate.  相似文献   
6.
Protein folding and quality control in the endoplasmic reticulum are critical processes for which our current understanding is far from complete. Here we describe the functional characterization of a new human 27.7-kDa protein (ERp27). We show that ERp27 is a two-domain protein located in the endoplasmic reticulum that is homologous to the non-catalytic b and b' domains of protein disulfide isomerase. ERp27 was shown to bind Delta-somatostatin, the standard test peptide for protein disulfide isomerase-substrate binding, and this ability was localized to the second domain of ERp27. An alignment of human ERp27 and human protein disulfide isomerase allowed for the putative identification of the peptide binding site of ERp27 indicating conservation of the location of the primary substrate binding site within the protein disulfide isomerase family. NMR studies revealed a significant conformational change in the b'-like domain of ERp27 upon substrate binding, which was not just localized to the substrate binding site. In addition, we report that ERp27 is bound by ERp57 both in vitro and in vivo by a similar mechanism by which ERp57 binds calreticulin.  相似文献   
7.
Biotechnology Letters - Ionic liquids (ILs) that dissolve biomass are harmful to the enzymes that degrade lignocellulose. Enzyme hyperthermostability promotes a tolerance to ILs. Therefore, the...  相似文献   
8.
Avidins represent an interesting group of proteins showing high structural similarity and ligand-binding properties but low similarity in primary structure. In this study, we show that it is possible to create functional chimeric proteins from the avidin protein family when applying DNA family shuffling to the genes of the avidin protein family: avidin, avidin related gene 2 and biotin-binding protein A. The novel chimeric proteins were selected by phage display biopanning against biotin, and the selected enriched proteins were characterized, displaying diverse features distinct from the parental genes, including binding to cysteine.  相似文献   
9.
Acidic pH of the Golgi lumen is known to be crucial for correct glycosylation, transport and sorting of proteins and lipids during their transit through the organelle. To better understand why Golgi acidity is important for these processes, we have examined here the most pH sensitive events in N‐glycosylation by sequentially raising Golgi luminal pH with chloroquine (CQ), a weak base. We show that only a 0.2 pH unit increase (20 µM CQ) is sufficient to markedly impair terminal α(2,3)‐sialylation of an N‐glycosylated reporter protein (CEA), and to induce selective mislocalization of the corresponding α(2,3)‐sialyltransferase (ST3) into the endosomal compartments. Much higher pH increase was required to impair α(2,6)‐sialylation, or the proximal glycosylation steps such as β(1,4)‐galactosylation or acquisition of Endo H resistance, and the steady‐state localization of the key enzymes responsible for these modifications (ST6, GalT I, MANII). The overall Golgi morphology also remained unaltered, except when Golgi pH was raised close to neutral. By using transmembrane domain chimeras between the ST6 and ST3, we also show that the luminal domain of the ST6 is mainly responsible for its less pH sensitive localization in the Golgi. Collectively, these results emphasize that moderate Golgi pH alterations such as those detected in cancer cells can impair N‐glycosylation by inducing selective mislocalization of only certain Golgi glycosyltransferases. J. Cell. Physiol. 220: 144–154, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
10.
Aberrant secretion of lysosomal hydrolases such as (pro)cathepsin D (proCD) is a common phenotypic change in many human cancers. Here we explore the underlying molecular defect(s) and find that MCF-7 breast and CaCo-2 colorectal cancer cells that are unable to acidify their endosomal compartments secreted higher amounts of proCD than did acidification-competent cancer cell types. The latter secreted equivalent amounts of proCD only after dissipation of their organellar pH gradients with NH(4)Cl. Assessing the critical steps that resulted in proCD secretion revealed that the Golgi-associated sorting receptor for CD, i.e. the cation-independent mannose-6-phosphate receptor (MPR300), was aberrantly distributed in acidification-defective MCF-7 cells. It accumulated mainly in late endosomes and/or lysosomes as a complex with its ligand (proCD or intermediate CD), as evidenced by its co-localization with both CD and LAMP-2, a late endosome/lysosome marker. Our immunoprecipitation analyses also showed that MCF-7 cells possessed 7-fold higher levels of receptor-enzyme complexes than did acidification-competent cells. NH(4)Cl induced similar receptor redistribution into LAMP-2-positive structures in acidification-competent cells but not in MCF-7 cells. The receptor also recovered its normal Golgi localization upon drug removal. Based on these observations, we conclude that defective acidification results in the aberrant secretion of proCD in certain cancer cells and interferes mainly with the normal disassembly of the receptor-enzyme complexes and efficient receptor reutilization in the Golgi.  相似文献   
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