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51.
The innate immune system acts in the first line of host defense against pathogens. One of the mechanisms used involves the early recognition and uptake of microbes by host professional phagocytes, through pattern recognition receptors (PRRs). These PRRs bind to conserved microbial ligands expressed by pathogens and initiate both innate and adaptative immune responses. Some PRRs located on the surface of dendritic cells (DCs) and other cells seem to play an important role in human immunodeficiency virus type 1 (HIV-1) transmission. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin, CD209 (DC-SIGN) and its homolog, DC-SIGN-related (DC-SIGNR or L-SIGN) receptors are PPRs able to bind the HIV-1 gp120 envelope protein and, because alterations in their expression patterns also occur, they might play a role in both horizontal and vertical transmission as well as in disseminating the virus within the host. This review aims to explore the involvement of the DC-SIGN and L-SIGN receptors in HIV-1 transmission from mother to child. 相似文献
52.
Benedetta Ludovica Pettorini MD Federica Novegno MD Alessandro Cianfoni MD Luca Massimi MD Pasquale De Bonis MD Giuseppe Esposito MD Massimo Caldarelli MD Gianpiero Tamburrini MD Concezio Di Rocco MD Felice Giangaspero MD § Libero Lauriola MD ∧ 《Brain pathology (Zurich, Switzerland)》2009,19(3):523-526
53.
Coiro V Casti A Jotti GS Rubino P Manfredi G Maffei ML Melani A Volta E Chiodera P 《Alcoholism, clinical and experimental research》2007,31(5):901-906
BACKGROUND: Alterations in the hypothalamic-pituitary-adrenal (HPA) axis in alcoholic patients have been reported in various experimental conditions. METHODS: To establish whether alcoholism affects the HPA axis activation during physical exercise, 10 recent abstinent alcoholic patients (age range: 33-45 years; duration of alcohol dependence: range 4-6 years) were tested by exercising on a bicycle ergometer. Ten age-matched healthy nonalcoholic men participated as controls. The workload was gradually increased at 3-minute intervals until exhaustion and lasted about 15 minutes for all subjects. Alcoholic patients were tested at 3 time points, at 4, 6, and 8 weeks after alcohol withdrawal, whereas controls were tested only once. Main outcome measurements were circulating levels of adrenocorticotropic hormone (ACTH) and cortisol and physiological variables during physical exercise [heart rate, blood pressure, ventilation, frequency of breathing, tidal volume, oxygen consumption (VO2), carbon oxide production (VCO2), and respiratory exchange ratio (R)]. RESULTS: Similar basal and exercise-induced changes in physiological variables were observed in controls and alcoholic patients in all tests. Basal levels of ACTH and cortisol were similar in all tests performed on alcoholic patients and on normal controls. In normal subjects, exercise induced a significant increase in plasma ACTH and serum cortisol levels, with peak levels at 20 minutes for ACTH (84% higher than baseline) and at 30 minutes for cortisol (70% higher than baseline). After 4 weeks of abstinence, slight but not significant ACTH/cortisol responses to physical exercise were observed in alcoholic patients (mean peaks were 10 and 18% higher than baseline, respectively, for ACTH and cortisol). By contrast, when the exercise test was repeated after 6 weeks abstinence, ACTH/cortisol levels rose significantly versus baseline (mean peak levels of ACTH and cortisol were 48 and 38% higher than baseline, respectively, for ACTH and cortisol). However, the hormonal responses were significantly lower than in the normal controls. At 8 weeks of abstinence, ACTH/cortisol responses were significantly higher than 2 weeks previously, and were not distinguishable from the increments observed in the normal controls (76 and 68% higher than baseline, respectively, for ACTH and cortisol). CONCLUSIONS: In concurrence with previous reports showing alterations of the HPA axis in the central nervous system in alcohol-dependent subjects, these data show a defect of the neuroendocrine mechanism(s) underlying the ACTH/cortisol response to physical exercise for at least a month after alcohol withdrawal, with reconstitution of a normal hormonal response at 8 weeks. 相似文献
54.
Arosio B Segat L Milanese M Galimberti L Calabresi C Zanetti M Trabattoni D Annoni G Crovella S Vergani C 《Aging clinical and experimental research》2007,19(5):406-409
BACKGROUND AND AIMS: Peptydil prolyl cis-trans isomerase (PIN-1), which specifically regulates the conformational changes following phosphorylation of several proteins, targets the inactive hyper-phosphorylated tau on the Thr231-Pro motif and directly restores its biological function. Interestingly, PIN-1 is oxidatively inhibited not only in Alzheimer's disease brain but also in the hippocampi of mild cognitive impairment (MCI) subjects. The PIN-1 gene is characterized by two single nucleotide polymorphisms (SNPs) in the promoter region which are associated with the risk of Alzheimer's disease. The aim of this study was to analyse the genotype and allele distributions of these PIN-1 SNPs in MCI subjects diagnosed respectively as amnestic MCI (a-MCI) and multiple impaired cognitive domains (mcd-MCI) on the basis of cognitive features. METHODS: -667 T/C and -842 C/G SNPs were genotyped by polymerase chain reaction (PCR) amplification and direct sequencing in 43 MCI subjects, with the intention of comparing -667 and -842 SNP frequencies with those previously described in 111 Alzheimer's disease patients (AD) and 73 healthy controls (HC). RESULTS: The allele frequencies of the -842 C/G SNP in a-MCI subjects are similar to those of AD subjects, while those of mcd-MCI are comparable to HC (G allele 83% in both a-MCI and AD; 95% and 94% in mcd-MCI and HC, respectively). A similar trend is also observed in -842 C/G genotypes. CONCLUSIONS: Since a-MCI is thought to be the preclinical form of AD, the similar genotype distribution of -842 SNP in AD and a-MCI, but not in mcd-MCI, suggests that it is potentially involved in the conversion of a-MCI to AD. In conclusion, these findings support the theory that polymorphisms of the PIN-1 gene can affect neurodegeneration and its clinical progression. 相似文献
55.
Valenti L Fracanzani AL Dongiovanni P Bugianesi E Marchesini G Manzini P Vanni E Fargion S 《The American journal of gastroenterology》2007,102(6):1251-1258
OBJECTIVES: Hyperferritinemia is frequently observed in nonalcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome characterized by hepatic insulin resistance and considered high cardiovascular risk. Iron depletion by phlebotomy has been reported to decrease insulin resistance in NAFLD in small, uncontrolled studies. Aims of this study were to define the relationship between ferritin and iron stores in patients with NAFLD, the effect of iron depletion on insulin resistance, and whether basal ferritin levels influence treatment outcome. METHODS: Subjects were included if ferritin and/or ALT were persistently elevated after 4 months of standard therapy. Sixty-four phlebotomized subjects were matched 1:1 for age, sex, ferritin, obesity, and ALT levels with patients who underwent lifestyle modifications only. Insulin resistance was evaluated by insulin levels, determined by RIA and the HOMA-R index, at baseline and after 8 months. RESULTS: Baseline ferritin levels were associated with body iron stores (P<0.0001). Iron depletion produced a significantly larger decrease in insulin resistance (P=0.0016 for insulin, P=0.0042 for HOMA-R) compared with nutritional counseling alone, independent of changes in BMI, baseline HOMA-R, and the presence of the metabolic syndrome. Iron depletion was more effective in reducing HOMA-R in patients in the top two tertiles of ferritin concentrations (P<0.05 vs controls), and in carriers of the mutations in the HFE gene of hereditary hemochromatosis (P<0.05 vs noncarriers). CONCLUSIONS: Given that phlebotomy reduces insulin resistance, which is associated with liver tissue damage, future studies should evaluate the effect of iron depletion on liver histology and cardiovascular end points. 相似文献
56.
57.
Maria Grazia Piancino Alessandro Tortarolo Francesco Macdonald Umberto Garagiola Ludovica Nucci Marco Brayda-Bruno 《Orthodontics & craniofacial research》2023,26(2):178-184
Objective
To evaluate mastication in a group of patients with adolescent idiopathic scoliosis (AIS) with a control group, by means of the prevalence of reverse chewing cycles (RCCs).Material and Methods
This study included a group of patients (N = 32; F = 24; M = 8; mean age ± SD = 14 ± 3 years) with a confirmed diagnosis of AIS and a group of control subjects (N = 32; F = 24; M = 8; mean age ± SD = 13 ± 6 years) without spinal disorders. Mastication was recorded with both a hard and a soft bolus, following a standardized protocol, and the prevalence of RCCs was compared between the groups.Results
The prevalence of RCCs was significantly higher in the AIS group, with both a soft and a hard bolus, compared to the control group (P < .001).Conclusion
The results of this study indicate that the presence of AIS influences mastication, one of the main functions of the stomatognathic system. A multidisciplinary approach to these patients may be relevant in providing the best possible treatment outcomes. 相似文献58.
Christian von Bodman Mika P. Matikainen Ricardo L. Favaretto Kazuhito Matsushita John P. Mulhall James A. Eastham Peter T. Scardino Oguz Akin Farhang Rabbani 《The journal of sexual medicine》2011,8(2):567-574
IntroductionThe impact of unfavorable pelvic anatomy on the likelihood of having a nerve sparing radical retropubic prostatectomy (RRP) and the potential correlation between pelvic dimensions and recovery of erectile function (EF) after RRP have not been previously evaluated.AimTo determine the impact of different pelvic bony and soft tissue dimensions as well as apical prostate depth on the likelihood of performing bilateral nerve sparing and on recovery of EF after RP.MethodsBetween November 2001 and June 2007, 644 potent men undergoing RRP had preoperative MRI where pelvimetry was performed with bilateral nerve sparing in 504 men. Outcomes including varying degrees of recovery of EF (level 1: normal; level 2: partial erections routinely sufficient for intercourse; level 3: partial erections occasionally sufficient for intercourse) were assessed. Median follow‐up was 44.1 (interquartile range: 29.2, 65.3) months. We evaluated independent predictors of performing a bilateral nerve sparing procedure and of recovery of EF using multivariable Cox proportional hazards methods.Main Outcome MeasuresLikelihood of performing bilateral nerve sparing as well as recovery of EF after RRP.ResultsPatients with higher clinical stage and biopsy Gleason score are less likely to undergo bilateral nerve sparing. Surgeon is also a factor in the likelihood of having bilateral nerve sparing RRP. On multivariate Cox regression analysis, factors predictive of recovery of EF were age, pretreatment erectile function, surgeon, and modified Charlson score. None of the pelvimetric dimensions were significant predictors of any degree of recovery of EF. However, the study is limited by its retrospective nature and by being based on MRI evaluations useful for cancer staging rather than anatomical evaluation of pelvimetric dimensions.ConclusionsWe did not find unfavorable pelvic anatomy to impact the likelihood of performing a nerve sparing procedure or to be predictive of any degree of recovery of EF after RRP. von Bodman C, Matikainen MP, Favaretto RL, Matsushita K, Mulhall JP, Eastham JA, Scardino PT, Akin O, and Rabban F. Pelvimetric dimensions do not impact upon nerve sparing or erectile function recovery in patients undergoing radical retropubic prostatectomy. 相似文献
59.
The objective of this study is to evaluate the safety and efficacy of vagus nerve stimulation (VNS) in very young children suffering from catastrophic epilepsy and status epilepticus. We reviewed files of 60 VNS-implanted children at our institution and we selected six very young patients, less than 3 years old (mean age at implant 1.6 years). All patients suffered from severe cognitive impairment and catastrophic epilepsy with underlying diagnosis of hemimegalencephaly (1), hypoxic-ischemic encephalopathy (1), tuberous sclerosis complex (1), and malignant migrating partial epilepsy of infancy (3). Three patients were VNS-implanted during admission at intensive care unit (ICU) after developing life-threatening status epilepticus. The mean follow-up time was 41.6 months. The VNS was implanted using a single cervical incision. No surgery-related complications were observed. Four of six children have shown a significant, persistent improvement in seizure control (range, 60-90%). In patients with status, insertion of the vagal nerve stimulator allowed early cessation of status and discharge from ICU. Quality of life and parental satisfaction improved and for three children there was some milestone evolution. Catastrophic epilepsy in infancy can be devastating and difficult to treat with drugs and surgery. If resective surgery is inappropriate or refused, VNS can be considered as a well-tolerated and effective procedure even in toddlers affected by severe epilepsy and multiple developmental disabilities. 相似文献
60.
Radiation-induced brain tumours after central nervous system irradiation in childhood: a review 总被引:3,自引:3,他引:0
Benedetta Ludovica Pettorini Young-Soo Park Massimo Caldarelli Luca Massimi Gianpiero Tamburrini Concezio Di Rocco 《Child's nervous system》2008,24(7):793-805
OBJECTS: Radiation-induced cerebral tumours constitute a significant risk for subjects undergoing radiotherapy for the management of cerebral neoplasms. Age-related cerebral vulnerability could be a specific factor in the genesis of these complications. METHODS: The pertinent literature of both paediatric and adult series has been reviewed. Three personal cases were added. RESULTS: One hundred forty-two paediatric second brain tumours were evaluated. Out of them, 69 were malignant gliomas, 33 meningiomas, 8 sarcomatous lesions and 13 low-grade astrocytomas. The average latency period for the appearance of the second tumour was 8 years. Among the second tumours occurring in adults, meningioma is the most common. In this subgroup, the latency period ranged between 16 and 30 years. CONCLUSION: Paediatric radiation-induced brain tumours differ from the adult counterpart for both the histological subtypes. These figures indicate a specific vulnerability of the infantile brain demonstrated by the most frequent occurrence of highly malignant lesions. 相似文献