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81.
Borensztajn K Chafa O Le Bonniec B Wajcman H Reghis A Fischer AM Tapon-Bretaudière J 《Thrombosis research》2005,116(2):115-120
We describe here five F7 mutations found in four patients without bleeding history, despite constitutional coagulation Factor VII (FVII) deficiency. All five mutations are missense and affect the catalytic domain of FVII (A191T, A191V, T239P, R224Q and M298I). The A191V and T239P mutations are novel and were found in homozygous patients with no clinical bleeding tendency. The patient diagnosed with the A191V mutation had a phenotype corresponding to a moderate type 1 FVII deficiency (FVII:C 4%, FVII:Ag 5%). The T239P mutation was found in a patient with mild type 2 FVII deficiency (FVII:C 25%, FVII:Ag 95%). Novel mutations are both in close vicinity to the charge-stabilizing system of FVII. Modeling studies allow understanding in part the molecular basis for the loss of function. 相似文献
82.
The arginine test is highly useful in the evaluation of short-stature children and adolescents. Extravasation of arginine can cause full-thickness skin necrosis that requires serious surgical intervention with aesthetic and functional sequellea. The authors describe a case of distal forearm skin necrosis caused by arginine extravasation that was treated by wide debridement and a combination of groin flap and later with split-thickness skin graft. The authors emphasize the need for early and active management of arginine extravasation injuries. 相似文献
83.
Miranda JA Oliveira RF Carneiro LA Santos RS Grober MS 《General and comparative endocrinology》2003,132(2):183-189
In the common Azorean rock-pool blenny, Parablennius parvicornis, males exhibit alternative reproductive morphologies: (1) larger males defend nest sites, provide parental care, have anal glands (involved in pheromone release), testicular glands, and low gonad:body weight ratio (GSI) and (2) smaller, younger, males do not defend nests, have reduced glands and high GSI. These smaller non-nesting males behave as satellites (associated with nests) or sneakers (moving among nests), attempting to achieve parasitic fertilizations via sperm competition. In non-mammals, arginine vasotocin (AVT) is a key hypothalamic peptide involved in the control of reproductive behavior and physiology, and several fish species that exhibit alternative male reproductive morphs show polymorphism in AVT brain chemistry. We conducted an immunocytochemical study to generate comparative data on this intertidal blenny. Our analysis showed no difference in AVT-immunoreactive cell number or size between the male morphs, which is consistent with studies on other fish, including blennies. The number of AVT cells was positively correlated to fish body mass, while cell size showed no such relation. If corrected for body mass, the smaller non-nesting males have significantly more cells than the large nesting males. Our data suggest that the size and number of forebrain AVT cells develops initially to allow for reproduction in the young non-nesting males and this pattern does not appear to change when males take on the nesting morphotype later in life. This result appears to be consistent in many fishes with alternative male morphotypes. 相似文献
84.
The sympathetic innervation of white adipose tissue (WAT) appears to be a dominant mechanism triggering lipolysis. The purpose of this study was to determine the neurochemical phenotype of neurons comprising the sympathetic outflow from brain to WAT. This was accomplished by injecting Siberian hamster WAT with a viral retrograde transneuronal tract tracer, the pseudorabies virus (PRV), in combination with immunocytochemical characterization of several neurotransmitters or their synthetic enzymes in the brain. Catecholaminergic (tyrosine hydroxylase [TH] and dopamine-beta-hydroxylase [DBH] immunoreactivity) and peptidergic (arginine vasopressin [AVP] and oxytocin [OXY] immunoreactivity) neurons were part of this outflow, but the percentage of double-labeled cells was small, consistent with previous studies. Brainstem PRV + TH- or PRV + DBH-labeled cells were in previously identified noradrenergic areas (A5, A6, and subcoeruleus, rostroventrolateral medulla [RVL], some reticular nuclei). Forebrain double labeling was greatest in the paraventricular (TH, AVP, OXY) and suprachiasmatic (AVP) nuclei, both implicated in the central control of lipolysis. Differences between the PRV double labeling reported here for WAT versus that of other sympathetic peripheral targets were PRV + DBH in A5 and RVL, and PRV + TH in RVL and in the lateral paragigantocellular and lateral reticular nuclei. Collectively, these results begin to identify the neurochemical identity of the sympathetic outflow from brain to WAT. 相似文献
85.
目的:评价联合应用精氨酸(arginine,Arg)和谷氨酰胺(glutamine,Glu)的肠外营养(parenteral nutri- tion,PN)对胃癌患者根治术后免疫功能影响。方法:将60例胃癌患者随机平分为四组:Arg组、Glu组、Arg+Glu组及常规PN组(Rou组)。术后第1天起各组均连续给予PN支持7d,均为等氮等热量。另取15例同期行择期手术的普外科腹部手术患者(其中胆囊息肉6例、胆囊结石9例)作为空白对照组。术前、术后第8天分别检测各组的细胞免疫和体液免疫指标。结果:术前60例胃癌患者的CD3、CD4、CD4/CD8、IgA、IgM及IgG均低于空白对照组(P<0.05),CD8则高于空白对照组(P<0.05)。术后第8天,IgA、IgM、IgG在Arg组、Glu组和Arg+Glu组三组之间差异无显著性,三组均高于Rou组(P<0.05);CD3、CD4的百分比及CD34/CD8比值在Arg组和Glu组组间差异无显著性,两组均高于Rou组(P<0.05),均低于Arg+Glu组(P<0.05);而CD8的百分比和CRP、C3、C4的浓度与上述相反,CD3、CD4及CD4/CD8在Arg+Glu组和Rou组组间差异有极为显著性(P<0.01)。结论:联合Arg和Glu增强的PN比单用Arg或Glu增强的PN更能增强胃癌患者根治术后细胞免疫功能。 相似文献
86.
K. Abe N. Matsuura H. Fujita K. Fujieda T. Kato Y. Nohara Y. Mikami N. Fukushima 《European journal of pediatrics》1982,139(2):118-120
Plasma prolactin (PRL) response to arginine was examined in 16 prepubertal and 18 pubertal children with constitutional short stature, 5 patients with hyperthyroidism and 4 patients with primary hypothyroidism. The mean basal concentration of plasma PRL was significantly higher (P<0.01) in primary hypothyroidism than in other groups. Arginine infusion elicited significant (P<0.05) rises in plasma PRL in all groups. The maximal increment of plasma PRL above the baseline level after arginine stimulation was significantly larger (P<0.05) in pubertal than in prepubertal females and was significantly smaller (P<0.05) in patients with hyperthyroidism than in age- and sex-matched controls. There was no sex difference in arginine-stimulated PRL secretion. These data suggest that arginine produces a significant increase in plasma PRL and the PRL response to arginine was greater in pubertal than in prepubertal children. Plasma PRL response to arginine is suppressed in children with hyperthyroidism and the basal plasma PRL is markedly elevated in primary hypothyroidism. 相似文献
87.
Prasada Rao S. Kodavanti Margarita C. Curras-Collazo 《Frontiers in neuroendocrinology》2010,31(4):479-496
Organohalogen compounds are global environmental pollutants. They are highly persistent, bioaccumulative, and cause adverse effects in humans and wildlife. Because of the widespread use of these organohalogens in household items and consumer products, indoor contamination may be a significant source of human exposure, especially for children. One significant concern with regard to health effects associated with exposure to organohalogens is endocrine disruption. This review focuses on PCBs and PBDEs as old and new organohalogens, respectively, and their effects on two neuroendocrine systems; thyroid hormones and the arginine vasopressin system (AVP). Regarding neuroendocrine effects of organohalogens, there is considerable information on the thyroid system as a target and evidence is now accumulating that the AVP system and associated functions are also susceptible to disruption. AVP-mediated functions such as osmoregulation, cardiovascular function as well as social behavior, sexual function and learning/memory are discussed. For both thyroid and AVP systems, the timing of exposure seems to play a major role in the outcome of adverse effects. The mechanism of organohalogen action is well understood for the thyroid system. In comparison, this aspect is understudied in the AVP system but some similarities in neural processes, shown to be targeted by these pollutants, serve as promising possibilities for study. One challenge in understanding modes of action within neuroendocrine systems is their complexity stemming, in part, from interdependent levels of organization. Further, because of the interplay between neuroendocrine and neural functions and behavior, further investigation into organohalogen-mediated effects is warranted and may yield insights with wider scope. Indeed, the current literature provides scattered evidence regarding the role of organohalogen-induced neuroendocrine disruption in the neuroplasticity related to both learning functions and brain structure but future studies are needed to establish the role of endocrine disruption in nervous system function and development. 相似文献
88.
Annette Hus-Citharel Olivier Levillain 《Pflügers Archiv : European journal of physiology》1999,437(3):423-431
Conflicting theories on the existence of several renal arginase isoenzymes remain in debate. Because the activity of arginase
is high in two embryologically different nephron segments of the Meriones shawi kidney, namely the cortical (CPST) and medullary (OSPST) proximal straight tubule and the outer medullary collecting duct
(OMCD), we postulate that these nephron segments may contain different isoforms. Isolated nephron segments were dissected
from collagenase-treated kidneys. Tubules were permeabilized with Triton X-100 (0.25%) and incubated with increasing Arg concentrations
to characterize the arginase activity. The results were as follows: (1) in OMCD, one arginase isoform (E1), characterized by a high Arg affinity (1.160 mM), was present; (2) in CPST, two arginase isoforms were discovered – one,
E1, had a similar K
m (1.407 mM) to that found in OMCD whereas the other (E2) had a low affinity for Arg (K
m =18.8 mM); and (3) in OSPST, two isoenzymes were present – E1 which had a K
m of 1.478 mM and the second isoform that we named E2 which had a K
m of 9.07 mM. In addition, arginase located in CPST and OMCD was strongly inhibited by Orn and Lys. The K
i value for Lys varied between 1.635 and 2.288 mM. Therefore, this work demonstrates that two arginase isoforms are present
in the kidney of Meriones shawi. Isoform E1 is present in the proximal tubule and the collecting duct whereas isoform E2 is restricted to the proximal tubule.
Received: 13 August 1998 / Accepted: 25 September 1998 相似文献
89.
Marco Marietta Ilaria Castelli Federica Piccinini Isabella Neri Marcello Bertesi Fabio Facchinetti Giuseppe Torelli 《International journal of laboratory hematology》2001,23(2):131-134
Platelet function was studied in 30 pregnant women: 14 normotensive (C), and 16 affected by pregnancy‐induced hypertension (PIH). Platelet aggregometry (PA) on platelet‐rich plasma according to Born was compared with the new PFA‐100? System (Dade International Inc, Miami, USA). This device evaluates platelet function (expressed in seconds as closure time, CT) in anticoagulated whole blood ex vivo at high shear rates. PA (expressed as percentage of light transmission) and CT were measured at baseline and after incubation with L‐Arginine (L‐Arg). MANOVA for repeated measures showed that L‐Arg incubation significantly decreased PA (F=7.2, P < 0.05) and increased CT (F=6.05, P < 0.05) in the whole population of pregnant women. Moreover, we analysed separately both parameters in C and in PIH subjects. No differences in PA were found in both groups, neither at baseline nor after L‐Arginine incubation. In contrast, CT was significantly longer in PIH in comparison to C before (95.9 s vs. 84 s, P < 0.05) as well after (115 s vs. 92 s, P < 0.05) L‐Arginine incubation. Data from PFA‐100? confirm our previous reports that during pregnancy the L‐Arginine: Nitric Oxide pathway regulates platelet function. In hypertensive patients a significant decrease in platelet function was found by using the PFA‐100? system. 相似文献
90.
To determine the central neural pathway which carries splanchnic osmosensory information to vasopressin (AVP) neurons in the hypothalamus, bilateral electrolytic lesions were placed in the ascending catecholaminergic fiber bundle, the locus coeruleus (LC), the locus subcoeruleus (subLC), the lateral parabrachial nucleus (LPB), the caudal periaqueductal gray (PAG) and the median preoptic nucleus (MPO). Six and seven days later, plasma AVP levels, plasma osmolality, mean arterial pressure and heart rate were measured following gastric infusion of hypertonic (598 mosm/kg; 2ml/4min) or isotonic (290 mosm/kg) saline in conscious rats with indwelling tail artery catheters and nasogastric tubes. The most effective pontine lesions, which were located in the ventral locus subcoeruleus (vsubLC) approximately 1.0 mm below the LC, decreased the AVP response to hypertonic gastric infusion by 59.7% (P < 0.05) as compared to sham-lesioned controls. In addition, unilateral vsubLC lesions dramatically reduced the catecholamine innervation of the ipsilateral paraventricular nucleus (PVN), as qualitatively determined with dopamine β-hydroxylase immunocytochemistry, suggesting that a pathway ascending with catecholaminergic fibers was disrupted. Lesions of the MPO were also very effective, decreasing the AVP response to hypertonic saline infusion by 60.3% (P < 0.05), suggesting that the MPO is an integral relay center in this pathway. On the other hand, LC, LPB and PAG lesions were ineffective. Systemic plasma osmolality or cardiovascular factors did not mediate the AVP response. These results demonstrate, for the first time, that splachnic osmotic information is transmitted to the hypothalamus via pathways within the ascending catecholaminergic fiber bundles, the MPO is a relay center where peripheral and central osmotic information may be integrated, and the LC, LPB and PAG are not part of the splanchnic osmotic pathway. 相似文献