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41.
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases.  相似文献   
42.
Uri Galili 《Immunology》2023,168(1):18-29
Two human natural anti-carbohydrate antibodies appeared in critical evolutionary events that brought primates and hominins to brink of extinction. The first is the anti-Gal antibody, produced in Old-World monkeys (OWM), apes and humans. It binds the carbohydrate-antigen ‘α-gal epitope’ (Galα1-3Galβ1-4GlcNAc-R) on carbohydrate-chains (glycans) synthesized by non-primate mammals, lemurs and New-World monkeys (NWM). The second is anti-N-glycolylneuraminic-acid (anti-Neu5Gc) antibody binding Neu5Gc on glycans synthesized by OWM, apes and most non-primate mammals. Ancestral OWM and apes synthesized α-gal epitopes and were eliminated ~20–30 million-years-ago (mya). Only few accidentally mutated offspring lacking α-gal epitopes, produced anti-Gal and survived. Hominin-populations living ~3 mya synthesized Neu5Gc and were eliminated, but few mutated offspring that accidently lost their ability to synthesize Neu5Gc, produced natural anti-Neu5Gc antibody. These hominins survived and ultimately evolved into present-day humans. It is argued that these two near-extinction events were likely to be the result of epidemics caused by highly virulent and lethal enveloped viruses that killed parental-populations. These viruses presented α-gal epitopes or Neu5Gc synthesized in host-cells of the parental-populations. Mutated offspring survived the epidemics because they were protected from the lethal virus by the natural anti-Gal or anti-Neu5Gc antibodies they produced due to loss of immune-tolerance to α-gal epitopes or to Neu5Gc, respectively.  相似文献   
43.
The hemodynamic effects of 20 to 40 mg of oral nifedipine were compared with those of intravenous nitroprusside in 11 patients with severe chronic congestive heart failure (CHF). In each patient, both drugs were administered to produce similar reduction of systemic vascular resistance (SVR) (29 ± 13% with nifedipine and 29 ± 12% with nitroprusside, difference not significant [NS]). At this comparable decrease in systemic vascular resistance, significant differences in hemodynamic responses to both drugs were noted: Nifedipine caused a smaller increase in cardiac index (20 ± 20% vs 40 ± 24%, p < 0.02) and a larger decrease in mean blood pressure than nitroprusside (16 ± 9% vs 8 ± 10%, p < 0.05). In addition, nifedipine produced a smaller decrease in mean pulmonary artery wedge pressure (13 ± 24% vs 36 ± 21%, p < 0.001) and pulmonary vascular resistance than nitroprusside (6 ± 42% vs 26 ± 46%, NS. Mean right atrial pressure decreased with nitroprusside, from 10 ± 7 to 5 ± 3 mm Hg (p < 0.05), but not with nifedipine (10 ± 7 mm Hg before and after nifedipine administration, NS). Left ventricular stroke work index increased with nitroprusside (20 ± 8 to 27 ± 9 g-m/m2, p < 0.05), but did not change with nifedipine (21 ± 9 vs 21 ± 10 g-m/m2, NS). These data show that nifedipine has an arteriolar dilatatory action in patients with CHF. However, compared with nitroprusside, nifedipine had a significantly larger hypotensive effect and had a lesser effect on right and left ventricular filling pressure, cardiac output and left ventricular function.  相似文献   
44.
The contributions of the autonomic nervous system and the cardiac pacing cells in the development of heat-acclimation-induced bradycardia were analyzed, and the effect of heat acclimation on the chronotropic response of the heart to heat stress (40° C) was studied. Rats were acclimated at 34° C for 0, 5, 14, 30 and 60 days. Heart rate (HR) was measured in conscious animals, using chronic subcutaneous electrodes. Sympathetic and parasympathetic influences were studied by IP administration of 0.1 and 1 mg/100 g body weight atropine and propranolol respectively, while intrinsic HR (HRi) was measured following administration of both drugs simultaneously. The effects of carbamylcholine and norepinephrine on the beating rate of isolated rat atria were investigated to study pacemaker responsiveness to neutrotransmitters. Up to day 14 of heat acclimation, bradycardia was attained by tonic parasympathetic acceleration (18%) and temporal sympathetic withdrawal (0.8% on day 14), to compensate for the gradually augmented HRi (2.5% and 8% on days 5 and 14, respectively). Following long-term acclimation HRi declined below pre-acclimation rate. This was associated with resumed sympathetic activity (16% and 10% on days 30 and 60 respectively) while parasympathetic activity continued to be high (18%). Tachycardia, known to occur with severe uncontrolled body hyperthermia, was attenuated following heat acclimation by 42%. It was concluded that during the initial phase of heat acclimation bradycardia is achieved primarily by changes in autonomic influences, while following long-term acclimation, changes in the intrinsic properties of the pacing cells (HRi) and the autonomic system both play a role.  相似文献   
45.
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47.
This review discusses the application of He-Ne laser irradiation to injured muscles at optimal power densities and optimal timing, which was found to significantly enhance (twofold) muscle regeneration in rats and, even more, in the cold-blooded toads. Multiple and frequent (daily) application of the laser in the toad model was found to be less effective than irradiation on alternate days. It was found that in the ischemia/reperfusion type of injury in the skeletal leg muscles (3 h of ischemia), infrared Ga-Al-As laser irradiation reduced muscle degeneration, increased the cytoprotective heat shock proteins (HSP-70i) content, and produced a twofold increase in total antioxidants. In vitro studies on myogenic satellite cells (SC) revealed that phototherapy restored their proliferation. Phototherapy induced mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) phosphorylation in these cells, probably by specific receptor phosphorylation. Cell cycle entry and the accumulation of satellite cells around isolated single myofibers cultured in vitro was also stimulated by phototherapy. Phototherapy also had beneficial effects on mouse, rat, dog and pig ischemic heart models. In these models, it was found that phototherapy markedly and significantly reduced (50-70%) the scar tissue formed after induction of myocardial infarction (MI). The phototherapeutic effect was associated with reduction of ventricular dilatation, preservation of mitochondria and elevation of HSP- 70i and ATP in the infarcted zone. It is concluded that phototherapy using the correct parameters and timing has a markedly beneficial effect on repair processes after injury or ischemia in skeletal and heart muscles. This phenomenon may have clinical applications.  相似文献   
48.

Purpose

Older age (>?60) has been considered a relative contraindication for bariatric surgery due to increased complication risk. This study examined the risks and benefits of bariatric surgery for patients older than 60 years in Canadian population.

Methods

This was a retrospective cohort study of the Ontario Bariatric Registry: a database recording peri-operative and post-operative outcomes of publicly funded bariatric surgeries across the province. Patients who completed 1 year follow-up, who underwent laparoscopic gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) between January 2010 and May 2013, were divided into older (>?60) and younger (>?60) cohorts, and outcomes were compared.

Results

Between January 2010 and May 2013, 3166 registry patients underwent LRYGB or LSG and completed 1-year follow-up. Of these, 204 (6.5%) were older than 60 years, with 175 (85.8%) undergoing LRYGB and 29 (14.2%) LSG. Demographics were similar, except for a higher number of males in the older group (59 (28.9%) versus 452 (15.3%) (p?<?0.001)). No significant difference in complication rate was noted (15% for younger cohort versus 13.8% (p?=?0.889)). The average percentage of excess weight loss was significantly higher in the younger population (60.72% versus 56.25% (p?<?0.05)) overall, however not significantly in the LSG group. Reduction in medication use post-surgery for management of co-morbidities was significantly higher in the older patients (??0.91 versus ??2.03 (p?<?0.001)).

Conclusion

The older cohort who underwent LRYGB or LSG was at no greater risk for intra-operative and post-operative complications and showed greater reduction in medication use post-surgery when compared to the younger cohort.
  相似文献   
49.
50.
Kuusk  Teele  Biancari  Fausto  Lane  Brian  Tobert  Conrad  Campbell  Steven  Rimon  Uri  D’Andrea  Vito  Mehik  Aare  Vaarala  Markku H. 《BMC urology》2015,15(1):1-4
Epididymal anomalies and patent processus vaginalis are frequently found in boys with cryptorchidism or hydrocele. We conducted this study to evaluate the association between epididymal anomalies and testicular location or patent processus vaginalis in boys with undescended testis or hydrocele. Children undergoing surgery with undescended testis (group A, 136 boys and 162 testes) or communicating hydrocele (group B, 93 boys and 96 testes) were included. Testicular locations and epididymal anomalies were investigated prospectively. An anomalous epididymis was defined as anomalies of epididymal fusion that consisted of loss of continuity between the testis, the epididymis, and the long looping epididymis. The epididymis was considered normal when a normal, firm attachment between the testis, the caput, and the cauda epididymis was present. The mean ages of groups A and B were 24.6 ± 19.7 (range, 8–52 months) and 31.4 ± 20.6 months (range, 10–59 months). The incidence of epididymal anomalies was significantly higher in group A than that in group B (65.4 % vs. 13.5 %, P < 0.001). The incidence of epididymal anomalies in boys with undescended testis was significantly different according to testis location. Epididymal anomalies were observed in 100 %, 91.4 %, and 39.3 % of cases when the testis was located in the abdomen, inguinal canal, and distal to the external inguinal ring, respectively (P < 0.001). We conclude that epididymal anomalies were more frequent in boys with undescended testis than in boys with hydrocele, and that these anomalies were more frequent when undescended testis was at a higher level. These results suggest that testicular location is associated with epididymal anomalies rather than patent processus vaginalis.  相似文献   
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