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71.
Y Chromosome and Mitochondrial DNA Characterization of Pasiegos, a Human Isolate from Cantabria (Spain) 总被引:3,自引:3,他引:3
N. Maca-Meyer P. Sánchez-Velasco C. Flores J.-M. Larruga A.-M. González A. Oterino F. Leyva-Cobián 《Annals of human genetics》2003,67(4):329-339
Mitochondrial DNA sequences and Y chromosome haplotypes were characterized in Pasiegos, a human isolate from Cantabria, and compared with those of other Cantabrian and neighbouring Northern Spain populations. Cantabria appears to be a genetically heterogeneous community. Whereas Lebaniegos do not differ from their eastern Basque and western Asturian and Galician neighbours, Pasiegos and other non‐Lebaniego Cantabrians show significant differences with all of them. Pasiegos are peculiar for their high frequencies of Y chromosomal markers (E‐M81) with North African assignation, and Y chromosomal (R‐SRY2627) and mtDNA (V, I, U5) markers related to northern European populations. This dual geographic contribution is more in agreement with the complex demographic history of this isolate, as opposed to recent drift effects. The high incidence in Cantabrians with pre‐V and V mtDNA haplotypes, considered as a signal of Postglacial recolonization in Europe from south‐western refugees, points to such refugees as a better candidate population than Basques for this expansion. However, this does not discount a conjoint recolonization. 相似文献
72.
B Deslaugiers Ph Vaysse JM Combes J Guitard J Moscovici M Visentin D Vardon J Bécue 《Surgical and radiologic anatomy : SRA》1994,16(2):173-177
Summary The dissection of 100 external jugular veins in 50 cadavers was the object of this anatomic study. A certain number of notions concerning the afferent veins, the mode of termination and the valvular system of this vessel were defined. 1)Afferent veins. Along its pathway toward the deep venous system, the external jugular vein successively received: the transverse cervical vein in 88 cases (88%), usually opposite the intersection of the external jugular vein with the dorsal border of the sterno- cleidomastoid muscle; the suprascapular vein in 47 cases (47%); the anterior jugular vein in 46 cases (46%); the cervical vein or anastomosis with the latter in 13 cases (13%). 2)Mode of termination. Forty-three subjects presented a symmetric mechanism. 100 anastomoses can be classed into three types: in 60 cases (60%), the external jugular vein flowed into the jugulo-subclavian venous confluence; in 36 cases (36%), in to the subclavian vein at a distance from its junction with the internal jugular vein; in 4 cases (4%) in to the trunk of the internal jugular vein. 3)Study of the valves. There were studied in 25 subjects (50 external jugular veins). The valves were found in the ostial and paraostial position in 49 out of 50 veins.
Contribution à l'étude des afférences et de la terminaison de la veine jugulaire externe
Résumé Cette étude anatomique repose sur la dissection de 100 vv. jugulaires externes chez 50 cadavres. Elle a permis de préciser un certain nombre de notions concernant les veines afférentes, le mode de terminaison et le système valvulaire de ce vaisseau. 1)Veines afférentes. Le long de son trajet vers le sytème veineux profond, la v. jugulaire externe reçoit successivement: la v. cervicale transverse dans 88 cas (88 %), habituellement en regard du croisement de la v. jugulaire externe avec le bord dorsal du m. sterno-cléido-mastoïdien ; la v. supra-scapulaire dans 47 cas (47 %); la v. jugulaire antérieure dans 46 cas (46 %) ; la v. céphalique ou une anastomose avec celle-ci dans 13 cas (13 %). 2)Mode de terminaison. Quarante trois sujets présentent un dispositif symétrique. Les 100 abouchements peuvent être classés en trois types : dans 60 cas (60 %) la v. jugulaire externe se déverse dans le confluent veineux jugulo-subclavier ; dans 36 cas (36 %), dans la v. subclavière à distance de sa réunion avec la v. jugulaire interne ; dans 4 cas (4 %) dans le tronc de la v. jugulaire interne. 3)Etude des valvules. Recherchées chez 25 sujets (50 vv. jugulaires externes), les valvules ont été retrouvées dans 49 cas sur 50 en position ostiale ou paraostiale.相似文献
73.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献
74.
Xiaoyu Wang Mingzhen Zhang Regina R. Woloshun Yang Yu Jennifer K. Lee Shireen R. L. Flores Didier Merlin James F. Collins 《Nutrients》2021,13(5)
Intestinal iron transport requires an iron importer (Dmt1) and an iron exporter (Fpn1). The hormone hepcidin regulates iron absorption by modulating Fpn1 protein levels on the basolateral surface of duodenal enterocytes. In the genetic, iron-loading disorder hereditary hemochromatosis (HH), hepcidin production is low and Fpn1 protein expression is elevated. High Fpn1-mediated iron export depletes intracellular iron, causing a paradoxical increase in Dmt1-mediated iron import. Increased activity of both transporters causes excessive iron absorption, thus initiating body iron loading. Logically then, silencing of intestinal Dmt1 or Fpn1 could be an effective therapeutic intervention in HH. It was previously established that Dmt1 knock down prevented iron-loading in weanling Hamp (encoding hepcidin) KO mice (modeling type 2B HH). Here, we tested the hypothesis that Dmt1 silencing combined with dietary iron restriction (which may be recommended for HH patients) will mitigate iron loading once already established. Accordingly, adult Hamp KO mice were switched to a low-iron (LFe) diet and (non-toxic) folic acid-coupled, ginger nanoparticle-derived lipid vectors (FA-GDLVs) were used to deliver negative-control (NC) or Dmt1 siRNA by oral, intragastric gavage daily for 21 days. The LFe diet reduced body iron burden, and experimental interventions potentiated iron losses. For example, Dmt1 siRNA treatment suppressed duodenal Dmt1 mRNA expression (by ~50%) and reduced serum and liver non-heme iron levels (by ~60% and >85%, respectively). Interestingly, some iron-related parameters were repressed similarly by FA-GDLVs carrying either siRNA, including 59Fe (as FeCl3) absorption (~20% lower), pancreatic non-heme iron (reduced by ~65%), and serum ferritin (decreased 40–50%). Ginger may thus contain bioactive lipids that also influence iron homeostasis. In conclusion, the combinatorial approach of FA-GDLV and Dmt1 siRNA treatment, with dietary iron restriction, mitigated pre-existing iron overload in a murine model of HH. 相似文献
75.
Daniel López-Padilla Francisco García-Río Adolfo Alonso-Arroyo Nuria Arenas Valls Alicia Cerezo Lajas Marta Corral Blanco Virginia Gallo González Milagros Llanos Flores María Martínez Redondo Natalia Martos Gisbert Elena Ojeda Castillejo Marta Padilla Bernáldez Marta Pérez Gallán Vania Prudencio Ribera Luis Puente Maestu Beatriz Recio Moreno Elena Rodríguez Jimeno Ana Sánchez Azofra José Ignacio de Granda-Orive 《Archivos de bronconeumologia》2021,57(2):146-147
76.
Hillarey K. Stone Katherine VandenHeuvel Alexander Bondoc Francisco X. Flores David K. Hooper Charles D. Varnell Jr 《American journal of transplantation》2021,21(12):4061-4067
Primary hyperoxaluria type 1 is a rare inherited disorder caused by abnormal liver glyoxalate metabolism leading to overproduction of oxalate, progressive kidney disease, and systemic oxalosis. While the disorder typically presents with nephrocalcinosis, recurrent nephrolithiasis, and/or early chronic kidney disease, the diagnosis is occasionally missed until it recurs after kidney transplant. Allograft outcomes in these cases are typically very poor, often with early graft loss. Here we present the case of a child diagnosed with primary hyperoxaluria type 1 after kidney transplant who was able to maintain kidney function, thanks to aggressive renal replacement therapy as well as initiation of a new targeted therapy for this disease. This case highlights the importance of having a high index of suspicion for primary hyperoxaluria in patients with chronic kidney disease and nephrocalcinosis/nephrolithiasis or with end stage kidney disease of uncertain etiology, as initiating therapies early on may prevent poor outcomes. 相似文献
77.
E D Flores R A Lange R G Cigarroa L D Hillis 《Journal of the American College of Cardiology》1990,16(1):74-79
Cocaine increases myocardial oxygen demand and paradoxically decreases oxygen supply by reducing coronary blood flow. Such "inappropriate" vasoconstriction also occurs with exercise, which causes intense vasoconstriction of coronary artery segments narrowed by atherosclerosis. This study was done to assess the cocaine-induced change in vasomotor tone of diseased and nondiseased coronary artery segments. In 18 patients (15 men, 3 women, aged 35 to 67 years), coronary artery areas in diseased and nondiseased segments were quantitated before and 15 min after administration of intranasal saline solution (6 patients) or cocaine (2 mg/kg body weight) (12 patients). No variables changed after intake of the saline solution. In response to cocaine, the luminal areas of diseased and nondiseased segments decreased, but the magnitude of vasoconstriction was greater in the diseased segments (mean +/- SD 29 +/- 23% versus 13 +/- 8%, p less than 0.05). Thus, cocaine causes vasoconstriction of diseased and nondiseased coronary artery segments, but its effect is particularly marked in the former. 相似文献
78.
Sarkar S Flores I Ron Y Derosa C Ozzello L Pestka S 《International journal of oncology》1995,7(1):17-24
Highly aggressive murine B16 melanoma was engineered to secrete IFN-alpha constitutively. Cells expressing IFN-alpha were injected into syngeneic C57BL/6 mice and the mice were monitored for tumor development. Secretion of IFN-alpha by B16 melanoma cells completely abrogated their tumorigenicity in syngeneic mice. LFN-alpha-secreting cells also abrogated the tumorigenicity of IFN-gamma-secreting and TNF-alpha-secreting cells when injected in combination whereas cells secreting either IFN-gamma or TNF-alpha grow progressively in mice when injected alone. Moreover, protected animals developed significant immunity against subsequent challenge with parental cells. Injection of parental cells and IFN-alpha-secreting cells together in a mixed tumor transplantation assay resulted in a significant reduction of tumorigenicity of the parental cells. Histopathological studies of the tissues from the injection site of the mice inoculated with a combination of parental and B16.IFN-alpha cells revealed the existence of a massive cellular infiltrate composed of lymphocytes and granulocytes at an early stage (7-11 days). In the later stages (22 days), no recognizable tumor tissue was detected. Injection of irradiated IFN-alpha-secreting cells in the mice carrying an established tumor completely prevented tumor development in 80% of the treated mice when injection was performed on the same side as the tumors. Injection of irradiated IFN-alpha-secreting cells in the contralateral site showed much less effect on the established tumor. Systemic antitumor effects on the established tumor can be enhanced by using a combination of irradiated IFN-alpha and IFN-gamma secreting cells as a vaccinating inoculum. 相似文献
79.
Kawai K Flores LG Nakagawa M Shikano N Jinnouchi S Tamura S Kubodera A 《Nuclear medicine communications》1999,20(2):153-157
The possibility of using L-meta-tyrosine (L-mTyr) with high metabolic stability and amino acid transport affinity was evaluated. mTyr was first separated into D- and L-isomers with high-performance liquid chromatography and both were labelled with non-carrier-mediated 125I. Biodistribution and pharmacological studies of radioiodinated mTyr in mice and rats were then performed. 125I-L-mTyr showed greater accumulation in the brain and the pancreas. It accumulated in the brain stereospecifically in the in vivo studies and by the L-tyrosine competitive energy dependent transport system in the in vitro studies. It was resistant to deiodination, appeared to have no retention mechanism and was rapidly excreted. 123I-L-mTyr has the potential of an amino acid transport marker, especially in the brain and the pancreas. 相似文献
80.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis. 相似文献