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11.
Senescence is accompanied by a reduced ability to respond to a variety of physical and behavioral stressors. A sizable literature has been devoted to the interplay between hypothalamic-pituitary-adrenocortical axis dysfunction and senescence; yet, the precise interactions remain an enigma. Adrenocorticotropic hormone (ACTH) is secreted in pulsatile bursts generating complex signals in the plasma compartment that must be “read” by adrenocortical cells in order to initiate appropriate secretory responses. We have previously demonstrated subtle differences between young and old rats in the pattern of fluctuations in plasma ACTH concentrations over time, despite no difference in mean levels. The present work addressed the physiological significance of these differences in the plasma ACTH signal by analyzing the corresponding plasma corticosterone concentration time series and the relationship between these two hormones over time. Time series of integrated 10-min ACTH and corticosterone concentrations were collected over 4 h at the time of diurnal activation and analyzed in the time and frequency domains. The time of onset of the diurnal surge occurred 20 min later in old rats, and the ratio of corticosterone to ACTH was less at the time of onset and peak of the diurnal surge. Corticosterone levels were lower in old rats and mean ACTH and corticosterone levels were correlated in young but not old rats, as were maximum levels of the two hormones. Cross-correlation of ACTH and corticosterone time series and comparison of spectra were consistent with smoother fluctuations in plasma corticosterone in old animals with less variability at time scales less than 55 min. We conclude that age may be associated with a delay in diurnal activation of the HPA axis, a loss of sensitivity of adrenal corticosterone secretion to plasma ACTH levels, and a relative loss of high frequency variability in the corticosterone signal, as seen in many physiological systems with age.  相似文献   
12.
To learn more about risk behaviors among men who have sex with men (MSM) in Vietnam and their prevalence of HIV, we conducted a study among MSM in Ho Chi Minh City (HCMC) to determine HIV-1 prevalence and behaviors associated with infection. This consisted of formative (35 MSM) and cross-sectional (600 MSM) studies at 72 sites, including 75 transvestites, 55 bisexuals, 10 sex workers, and 460 other MSM. Only 5.3% cohabited with a wife/girlfriend, but 30% reported ever having sex with a female. Prevalence of HIV was 8%, ranging from 33% in sex workers to 7% among transvestites and other MSM. Injecting drugs, selling sex, being 20–40 years old, having less than 6 years of education, and having more than five male anal sex partners in the past month were associated with being HIV-infected. MSM are an HIV bridge group, and should be included in sentinel surveillance. Targeted interventions should be implemented.  相似文献   
13.
In Vietnam, the first three cases of Allo-BMT were successfully performed in 1995 at the Blood Transfusion and Hematology Hospital (BT-H) of Ho Chi Minh City. Donors were HLA fully matched siblings (HLA-A, HLA-B and HLA-DRB1). The patients were a 26-year-old man with CML in chronic phase (CP), a 12-year-old woman with beta-thalassemia/Hb E and a 9-year-old girl with beta-thalassemia/Hb E. All patients were engrafted with the median time to recover ANC>0.5 x 10(9)/l, and platelet count >20 x 10(9)/l was 16 and 38 days. At 12 years after transplantation, all three patients are alive and well. Today, Vietnam has five SCT centers; in the north, there are three centers: 108 Military Hospital, Pediatric Institute and Blood transfusion and Hematology Institute; in the middle of Vietnam is Hue Hospital and in the south, the BT-H Hospital of Ho Chi Minh City. Until now, 65 patients have had SCT in Vietnam; among them, 52 patients had SCT at the BT-H Hospital, Ho Chi Minh City. Because of no connection of data between different SCT centers, we present here only the results performed at the BT-H Hospital, Ho Chi Minh City. With Allo-SCT we performed 19 cases with 3 procedures: BMT (4 cases), PBSC (6 cases) and cord blood transplantation (9 cases); patients were diagnosed with AML (n=7), ALL (n=1), CML (n=5) and beta-thalassemia (n=6). Following transplantation, 7 patients (36.84%) relapsed, 12 (63.16%) remained alive and overall survival times: 6.81+/-1.35 years, disease-free survival times: 6.69+/-1.4 years (range 0.5-12 years). With Auto-SCT: since November 1996, we have performed 33 cases of autologous PBSC transplantation consisting of without cryopreservation (24 cases) and with cryopreservation (9 cases); patients were diagnosed with AML in CR1 (n=21), ALL in CR1 (n=6), CML in CP (n=5) and non-Hodgkin's lymphoma in CR1 (n=1). The median age of the patients was 35 years (range 18-46). The median time to recover ANC >0.5 x 10(9)/l and platelet count >20 x 10(9)/l was 14 days (range 9-25 days) and 35 days (range 9-120 days). Following transplantation, 18 patients (54.50%) relapsed, 15 (45.45%) remained alive and overall survival times: 5.74+/-0.82 years and disease-free survival times: 5.48+/-0.92 years. There was no statistically significant difference of overall survival and disease-free survival between Allo-SCT and Auto-SCT procedures (P>0.05). These preliminary data suggest that HSCTs have been used as one of the standard treatments for hematological diseases and malignancies in Vietnam and that cord blood is an alternative source of hematopoietic stem cells for allogeneic transplantation in children.  相似文献   
14.
CD19 chimeric antigen receptor T (CAR T)-cell therapy with axicabtagene ciloleucel (axi-cel) for relapsed or refractory (R/R) large B-cell lymphoma (LBCL) may lead to durable remissions, however, prolonged cytopenias and infections may occur. In this single center retrospective study of 85 patients, we characterized immune reconstitution and infections for patients remaining in remission after axi-cel for LBCL. Prolonged cytopenias (those occurring at or after day 30 following infusion) were common with ≥grade 3 neutropenia seen in 21 of 70 (30%) patients at day 30 and persisting in 3 of 31 (9.7%) patients at 1 year. B cells were undetectable in 30 of 34 (88.2%) patients at day 30, but were detected in 11 of 19 (57.9%) at 1 year. Median immunoglobulin G levels levels reached a nadir at day 180. By contrast, CD4 T cells decreased from baseline and were persistently low with a median CD4 count of 155 cells/mL at 1 year after axi-cel (n=19, range: 33– 269). In total, 23 of 85 (27.1%) patients received intravenous immunoglobulins after axi-cel, and 34 of 85 (40%) received granulocyte-colony stimulating factor. Infections in the first 30 days occurred in 31 of 85 (36.5%) patients, of which 11 of 85 (12.9%) required intravenous antibiotics or hospitalization (“severe”) and were associated with cytokine release syndrome, neurotoxicity, tocilizumab use, corticosteroid use, and bridging therapy on univariate analyses. After day 30, seven severe infections occurred, with no late deaths due to infection. Prolonged cytopenias are common following axi-cel therapy for LBCL and typically recover with time. Most patients experience profound and prolonged CD4 T-cell immunosuppression without severe infection.  相似文献   
15.
16.

Three new steroidal saponins, aspiletreins A–C (13), together with 2H-chromen-2-one (4), and α-tocopherol (5), were isolated from whole Aspidistra letreae plants collected in Vietnam. Their structures were elucidated by a combination of spectroscopic analyses, including 1D- and 2D-NMR, IR, and HRESIMS, and by comparison with the reported data in the literature. Compounds 13 exhibited moderate cytotoxicities against the LU-1, HeLa, MDA-MB-231, HepG2, and MKN-7 human cancer cell lines, with IC50 values ranging from 7.69?±?0.40 to 20.46?±?3.11 µM.

  相似文献   
17.
BACKGROUND: Tuberculous meningitis (TBM) caused by Mycobacterium tuberculosis resistant to 1 or more antituberculosis drugs is an increasingly common clinical problem, although the impact on outcome is uncertain. METHODS: We performed a prospective study of 180 Vietnamese adults admitted consecutively for TBM. M. tuberculosis was cultured from the cerebrospinal fluid (CSF) of all patients and was tested for susceptibility to first-line antituberculosis drugs. Presenting clinical features, time to CSF bacterial clearance, clinical response to treatment, and 9-month morbidity and mortality were compared between adults infected with susceptible and those infected with drug-resistant organisms. RESULTS: Of 180 isolates, 72 (40.0%) were resistant to at least 1 antituberculosis drug, and 10 (5.6%) were resistant to at least isoniazid and rifampicin. Isoniazid and/or streptomycin resistance was associated with slower CSF bacterial clearance but not with any differences in clinical response or outcome. Combined isoniazid and rifampicin resistance was strongly predictive of death (relative risk of death, 11.63 [95% confidence interval, 5.21-26.32]) and was independently associated with human immunodeficiency virus infection. CONCLUSIONS: Isoniazid and/or streptomycin resistance probably has no detrimental effect on the outcome of TBM when patients are treated with first-line antituberculosis drugs, but combined isoniazid and rifampicin resistance is strongly predictive of death.  相似文献   
18.
The pathogenesis of coma in severe Plasmodium falciparum malaria remains poorly understood. Obstruction of the brain microvasculature because of sequestration of parasitized red blood cells (pRBCs) represents one mechanism that could contribute to coma in cerebral malaria. Quantitative postmortem microscopy of brain sections from Vietnamese adults dying of malaria confirmed that sequestration in the cerebral microvasculature was significantly higher in patients with cerebral malaria (CM; n = 21) than in patients with non-CM (n = 23). Sequestration of pRBCs and CM was also significantly associated with increased microvascular congestion by infected and uninfected erythrocytes. Clinicopathological correlation showed that sequestration and congestion were significantly associated with deeper levels of premortem coma and shorter time to death. Microvascular congestion and sequestration were highly correlated as microscopic findings but were independent predictors of a clinical diagnosis of CM. Increased microvascular congestion accompanies coma in CM, associated with parasite sequestration in the cerebral microvasculature.  相似文献   
19.

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.  相似文献   
20.

BACKGROUND:

Celiac disease and eosinophilic esophagitis are usually considered to be separate gastrointestinal diseases; however, it appears that they may coexist more often than would be expected. It is unknown whether eosinophilic esophagitis in patients with celiac disease responds to a gluten-free diet.

OBJEVTIVES:

To examine the clinical, endoscopic and histological features of children with both conditions to evaluate whether eosinophilic esophagitis responds to a gluten-free diet.

METHODS:

From January 1, 2009, to June 30, 2011, the medical records of children <18 years of age diagnosed with eosinophilic esophagitis and/or celiac disease were reviewed. Patients with clinical, endoscopic and histological diagnoses of both diseases were identified and included. These findings were analyzed, as were laboratory results, treatment and follow-up.

RESULTS:

During the study period, there were 206 celiac disease patients, 86 eosinophilic esophagitis patients and nine (4.4% of total celiac) patients with both diagnoses. Gluten-free diet was the primary treatment for both conditions in seven of nine (78%) cases. In six of these seven (86%) patients, no endoscopic or histological improvement of eosinophilic esophagitis was observed, while in one patient, histological remission of esophageal eosinophilia occurred while on a gluten-free diet.

CONCLUSION:

The prevalence of eosinophilic esophagitis in patients with celiac disease was 4.4%, confirming a higher than expected prevalence of eosinophilic esophagitis compared with the general population. In patients with celiac disease, a gluten-free diet did not appear to induce remission of coexistent endoscopic and histological features of eosinophilic esophagitis.  相似文献   
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