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Recent studies have developed varied delivery systems incorporating natural compounds to improve the limitations of plant extracts for clinical use while enabling their controlled release at treatment sites. For the first time, ethanolic limeberry extract (Triphasia trifolia) has been successfully encapsulated in thermo-sensitive chitosan hydrogels by a facile in situ loading. The extract-incorporated chitosan hydrogels have a pH value of nearly 7.00, gelation temperatures in the range of 37-38 °C, and exhibit an open-cell porous structure, thus allowing them to absorb and retain 756 % of their mass in water. The in vitro extract release from the hydrogels is driven by both temperature and pH, resulting in more than 70 % of the initial extract being released within the first 24 h. Although the release half-life of hydrogels at pH 7.4 is longer, their release capacity is higher than that at pH 6.5. Upon a 2 °C increase in temperature, the time to release 50 % initial extract is sharply reduced by 20-40 %. The release kinetics from the hydrogels mathematically demonstrated that diffusion is a prominent driving force over chitosan relaxation. Consequently, the developed hydrogels encapsulating the limeberry extract show their heat and pH sensitivity in controlled release for treating chronic wounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The aim of this study was to compare the efficacy and safety of transradial approach (TRA) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) with the efficacy and safety of transfemoral approach (TFA). We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies (OS) reporting the outcomes of TRA versus TFA in CTO PCI. The primary end point was procedural success. Secondary end points included access-site complications, in-hospital adverse events, procedural efficacy outcomes, and 30-day all-cause mortality. A total of 28,754 CTO PCI cases from 19 studies were included (2 RCTs and 17 OS). The pooled mean J-CTO score is 2.3. The main analysis showed a trend toward a higher success rate for TRA (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.00 to 1.38), but this was not the case in the secondary analysis, which included only RCTs and OS with moderate risk of bias (OR 0.99, 95% CI 0.81 to 1.22). TRA was associated with significant reductions in access-site complications (OR 0.33, 95% CI 0.24 to 0.45) and major bleeding (OR 0.34, 95% CI 0.20 to 0.59), and a similar risk of other in-hospital adverse events and 30-day mortality (p >0.05) to that of TFA. Moreover, there was less fluoroscopy time (minutes) and contrast volume use (ml) in the transradial CTO PCI (mean difference: -6.19 [-10.98 to -1.40] and -22.14[-34.56 to -9.72], respectively). In conclusion, the transradial PCI in appropriate CTO lesions was associated with a lower incidence of access-site complications/major bleeding than was TFA and a similar other periprocedural complications rate, without compromising procedural success., Competing Interests: Declaration of Interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:, (Copyright © 2023 Elsevier Inc. All rights reserved.)

A coal-fired power plant's operation can release radioactive nuclides and radon gas into the environment, affecting the surrounding ecosystem. In this work, the collective effective dose due to the inhalation and the consumption of food containing the deposited radionuclides from the atmospheric release of the plants were evaluated. The results show that the radioactivity concentration in coal and fly ash samples depends on the origin of feed coal. The distribution of Th and U radionuclides in the 6a1 dust coal and bituminous coal is different. In general, the collective effective dose for different organs due to radiation exposure from the atmospheric release of two surveyed CFPP complexes are lower than the corresponding value published by UNSCEAR., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Comprehensive profiling of actionable mutations in non-small cell lung cancer (NSCLC) is vital to guide targeted therapy, thereby improving the survival rate of patients. Despite the high incidence and mortality rate of NSCLC in Vietnam, the actionable mutation profiles of Vietnamese patients have not been thoroughly examined. Here, we employed massively parallel sequencing to identify alterations in major driver genes (EGFR, KRAS, NRAS, BRAF, ALK and ROS1) in 350 Vietnamese NSCLC patients. We showed that the Vietnamese NSCLC patients exhibited mutations most frequently in EGFR (35.4%) and KRAS (22.6%), followed by ALK (6.6%), ROS1 (3.1%), BRAF (2.3%) and NRAS (0.6%). Interestingly, the cohort of Vietnamese patients with advanced adenocarcinoma had higher prevalence of EGFR mutations than the Caucasian MSK-IMPACT cohort. Compared to the East Asian cohort, it had lower EGFR but higher KRAS mutation prevalence. We found that KRAS mutations were more commonly detected in male patients while EGFR mutations was more frequently found in female. Moreover, younger patients (<61 years) had higher genetic rearrangements in ALK or ROS1. In conclusions, our study revealed mutation profiles of 6 driver genes in the largest cohort of NSCLC patients in Vietnam to date, highlighting significant differences in mutation prevalence to other cohorts.

Background and Aim: Vietnam's burden of liver cancer is largely due to its high prevalence of chronic hepatitis B virus (HBV) infection. This study aimed to examine healthcare workers' (HCWs) knowledge, attitude and practices regarding HBV prevention and management., Methods: A cross-sectional survey among health care workers working at primary and tertiary facilities in two Northern provinces in Vietnam in 2017. A standardized questionnaire was administered to randomly selected HCWs. Multivariate regression was used to identify predictors of the HBV knowledge score., Results: Among the 314 participants, 75.5% did not know HBV infection at birth carries the highest risk of developing chronic infection. The median knowledge score was 25 out of 42 (59.5%). About one third (30.2%) wrongly believed that HBV can be transmitted through eating or sharing food with chronic hepatitis B patients. About 38.8% did not feel confident that the hepatitis B vaccine is safe. Only 30.1% provided correct answers to all the questions on injection safety. Up to 48.2% reported they consistently recap needles with two hands after injection, a practice that would put them at greater risk of needle stick injury. About 24.2% reported having been pricked by a needle at work within the past 12 months. More than 40% were concerned about having casual contact or sharing food with a person with chronic hepatitis B infection (CHB). In multivariate analysis, physicians scored significantly higher compared to other healthcare professionals. Having received training regarding hepatitis B within the last two years was also significantly associated with a better HBV knowledge score., Conclusions: Findings from the survey indicated an immediate need to implement an effective hepatitis B education and training program to build capacity among Vietnam's healthcare workers in hepatitis B prevention and control and to dispel hepatitis B stigma., Competing Interests: The authors have declared that no competing interests exist.

Background and Aim: Infection at birth due to mother-to-child (MTC) transmission is the most common cause of chronic hepatitis B virus (HBV) infection in Vietnam. This study was undertaken to examine the knowledge, attitudes, and practices of pregnant women and mothers in Vietnam concerning HBV prevention and immunization., Methods: A cross-sectional survey was conducted in Quang Ninh and Hoa Binh provinces in 2017. A standardized questionnaire was administered to women when they received care at primary and tertiary maternal health clinics. Multivariate regression was used to identify predictors of HBV knowledge and practices., Results: Among the 380 women surveyed, 50.3% were pregnant and 49.7% were postpartum. Despite 70.3% of participants reported having received information about HBV during their pregnancy, only 10.8% provided correct answers to all questions regarding HBV transmission routes and preventive measures. Around half of the participants incorrectly believed that HBV is transmitted through sneezing, contaminated water or sharing foods with chronic HBV patients. Although 86.1% of participants believed that HBV vaccination is necessary for infants, only 66.1% responded they were definitely willing to have their own child vaccinated within 24 hours. More than a third of participants expressed concern about having casual contacts or sharing foods with chronic HBV patients. In multivariate analysis, having received information about HBV during their pregnancy was significantly associated with better HBV knowledge score. Delivery at provincial level clinics was a strong predictor for perinatal HBV screening and hepatitis B birth dose administration., Conclusions: The results highlight the need to prioritize educating pregnant women and mothers in future public health campaigns in order to increase knowledge, reduce misperception, and improve hepatitis B vaccine birth dose coverage in Vietnam., Competing Interests: The authors have declared that no competing interests exist.

Transplantation centers have historically considered a history of multiple myeloma as a contraindication to kidney transplantation due to high recurrence rates and poor transplant survival. However, there have been significant advances in the treatment of multiple myeloma, with improved patient survival, which may allow for successful kidney transplantation in these patients. We report on 4 patients who underwent kidney transplantation at our institution between 2009 and 2015 after having achieved a very good partial response or better with chemotherapy and autologous stem cell transplantation. All 4 patients received kidneys from living donors; 2 underwent induction therapy with basiliximab, and 2, with thymoglobulin. One patient had progression of myeloma, which responded well to therapy. All had functioning transplants at 1 year after kidney transplantation. No patients experienced a rejection episode or infections with BK polyomavirus or cytomegalovirus, with follow-up ranging from 16 to 58 months after kidney transplantation. Our experience suggests that kidney transplantation is feasible in a subset of patients with multiple myeloma. Future studies are necessary to compare outcomes in these patients with other high-risk patients undergoing kidney transplantation., (Copyright © 2017 National Kidney Foundation, Inc. All rights reserved.)

Objectives: This study evaluates the sensitivity and specificity of stenosis index (SI), which accounts for the entire spectral Doppler waveform, to detect significant transplant hepatic arterial stenosis., Materials and Methods: In this institutional review board-approved, HIPAA compliant study, we retrospectively analyzed 69 patients who had catheter angiography for suspected transplant hepatic arterial stenosis (THAS) between January 2006 and December 2010; all patients had Doppler ultrasound within 30 days before angiography. Patients with angiographic stenosis requiring intervention were considered positive for THAS. Stenosis index was calculated from each patient's spectral Doppler ultrasound images by obtaining the ratio of the area under the high-frequency signal to low-frequency signal in the spectral Doppler. Resistive index (RI) and pulsatility index (PI) were also calculated. Receiver operator curve analysis was performed and the area under the curve (AUC) was compared among the three metrics., Results: Forty-eight of 69 patients had THAS by angiography requiring intervention; 21patients had no angiographic evidence of THAS. SI was significantly different (P < .001) between patients with THAS (SI = 1.04 ± 0.20) and those without THAS (SI = 1.39 ± 0.30). Stenosis index had an AUC of 0.86 for detecting THAS, which was significantly higher than that from RI (AUC = 0.68, P = .038 for the comparison) and PI (AUC = 0.70, P = .029). For SI < 1.35, the sensitivity for THAS was 94% and specificity was 52%. For RI < 0.5, the sensitivity was 96% and the specificity was 29%., Conclusions: Stenosis index is more accurate than the resistive index and the pulsatility index for detecting transplant hepatic artery stenosis., (© 2016 by the American Institute of Ultrasound in Medicine.)

Improving long-term transplant and patient survival is still an ongoing challenge in kidney transplant medicine. Our objective was to identify the subsequent risks of new-onset diabetes after transplant (NODAT) and acute rejection (AR) in the first year post-transplant in predicting mortality and transplant failure. A total of 4687 patients without preexisting diabetes (age 2-20 years, 2004-2010) surviving with a functioning transplant for longer than 1 year with at least one follow-up report were identified from the OPTN/UNOS database as of September 2014. Study population was stratified into four mutually exclusive groups: Group 1, patients with a history of AR; Group 2, NODAT+; Group 3, NODAT+ AR+; and Group 4, the reference group (neither). Multivariate regression was used to analyze the relative risks for the outcomes of transplant failure and mortality. The median follow-up time was 1827 days after 1 year post-transplant. AR was associated with an increased risk of adjusted graft and death-censored graft failure (HR 2.87, CI 2.48-3.33, P < .001 and HR 2.11, CI 1.81-2.47, P < .001), respectively. NODAT and AR were identified in 3.5% and 14.5% of all study patients, respectively. AR in the first year post-transplant was a major risk factor for overall and death-censored graft failure, but not mortality. However, NODAT was not a risk factor on graft survival or mortality., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The umpolung of glycals with samarium diiodide offers a simple route to novel carbohydrate-derived nucleophilic reagents in a single step using a readily available reductant. The corresponding allyl samarium reagent that arises from the hexose series reacts with ketones at the C3 position with high stereoselectivity; carbon-carbon bond formation takes place only anti to the substituent at the C4 position of the dihydropyran ring. For the sialic acid series, the completely regio- and stereoselective coupling process of the samarium reagent occurs at the anomeric carbon atom and provides a new approach to the α-C-glycosides of N-acetyl neuraminic acid., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: In imminently dying patients, mechanical ventilation withdrawal is often a comfort measure and avoids prolonging the dying process., Objective: The aim of the study was to identify factors associated with palliative withdrawal of mechanical ventilation and time to death after extubation., Methods: Logistic regression models were used to identify factors associated with palliative withdrawal of mechanical ventilation. Cox proportional hazards models were used to determine factors associated with time to death after extubation. We retrospectively evaluated 322 patients who died on mechanical ventilation or after palliative ventilator withdrawal at a single tertiary care center., Results: Of the 322 ventilated deaths, 159 patients had palliative withdrawal of mechanical ventilation and 163 patients died on the ventilator. Clinical service was associated with palliative withdrawal of mechanical ventilation: Patients withdrawn from the ventilator were less likely to be on the surgery service and more likely to be on the neurology/neurosurgical service. The median time to death was 0.9 hours (range 0-165 hours). Fraction of inspired oxygen (FIO2) greater than 70% (hazard ratio [HR] 1.92, 95% confidence interval [CI ]1.24-2.99) and a requirement for vasopressors (HR 2.06, 95% CI 1.38-3.09) were associated with shorter time to death. Being on the neurology/neurosurgical service at the time of ventilator withdrawal was associated with a longer time to death (HR 0.60, 95% CI 0.39-0.92)., Conclusions: Palliative withdrawal of mechanical ventilation was performed in only half of dying mechanically ventilated patients. Because clinical service rather than physiologic parameters are associated with withdrawal, targeted interventions may improve withdrawal decisions. Considering FIO2 and vasopressor requirements may facilitate counseling families about anticipated time to death.

Purpose: We introduce a new technique for quantifying arterial stenoses, stenosis index (SI), using frequency analysis of the spectral Doppler waveform., Methods: Spectral Doppler waveforms obtained distal to arterial stenoses were enveloped, and the envelope was transformed into the frequency domain via Fourier transform. Stenosis index represents the ratio of the power in high-frequency harmonics to the power in the fundamental frequency.Stenosis index was compared with resistive index (RI), pulsatility index (PI), and acceleration time using 1000 computer simulations of waveforms from arteries distal to transplanted renal artery stenoses using Kendall tau correlation coefficients and receiver operating characteristic curve analyses., Results: The mean r's using Kendall tau correlation for SI, RI, and PI were 0.58, 0.31, and 0.45, respectively. The 95% confidence intervals for increase in r's for SI versus RI and PI to the degree of stenosis (none, mild, and severe) in the 1000 computer simulations were 0.22 to 0.34 and 0.07 to 0.19. The difference between the areas under the curves for SI versus RI and PI for normal artery versus mild stenosis was 0.26 to 0.44 and 0.078 to 0.24. Stenosis index and acceleration time were not significantly different., Conclusions: In computational models, SI outperformed RI and PI in correlation and receiver operating characteristic curve analysis. Further testing of SI is warranted.

Purpose: Overactive bladder is subtyped into overactive bladder-wet and overactive bladder-dry, based on the presence or absence, respectively, of urgency incontinence. To better understand patient and physician perspectives on symptoms among women with overactive bladder-wet and overactive bladder-dry, we performed patient focus groups and interviews with experts in urinary incontinence., Materials and Methods: Five focus groups totaling 33 patients with overactive bladder symptoms, including 3 groups of overactive bladder-wet and 2 groups of overactive bladder-dry patients, were conducted. Topics addressed patient perceptions of overactive bladder symptoms, treatments and outcomes. A total of 12 expert interviews were then done in which experts were asked to describe their views on overactive bladder-wet and overactive bladder-dry. Focus groups and expert interviews were transcribed verbatim. Qualitative data analysis was performed using grounded theory methodology, as described by Charmaz., Results: During the focus groups sessions, women screened as overactive bladder-dry shared the knowledge that they would probably leak if no toilet were available. This knowledge was based on a history of leakage episodes in the past. Those few patients with no history of leakage had a clinical picture more consistent with painful bladder syndrome than overactive bladder. Physician expert interviews revealed the belief that many patients labeled as overactive bladder-dry may actually be mild overactive bladder-wet., Conclusions: Qualitative data from focus groups and interviews with experts suggest that a spectrum exists between very mild overactive bladder-wet and severe overactive bladder-wet. Scientific investigations are needed to determine whether urgency without fear of leakage constitutes a unique clinical entity., (Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

In the present work, we investigated the multielemental elution behavior of metal ions absorbed on iminodiacetic acid (IDA) chelating resin by using hydrogen peroxide (H(2)O(2)) as an eluent. As a result, V(V), Mo(VI), W(VI), Nb(V) and Ta(V) were efficiently eluted by H(2)O(2). In contrast, other metal ions were rarely recovered. The oxidation states of V(V), Mo(VI), and W(VI) were not changed through the H(2)O(2) eluting process, checked by X-ray photoelectron analysis. In addition, the UV-vis adsorption spectra and IR spectra of V(V), Mo(VI) and W(VI) in the H(2)O(2) eluent suggested the formation of metal-peroxo complexes through H(2)O(2) elution. The desorption of these metal ions from IDA functional groups is explained in term of destabilization along with the coordination of peroxo-ligands to the V(V)-, Mo(VI)- and W(VI)-IDA complexes, and a decrease in the adsorption capacity by electrostatic repulsion between dissociated carboxylic groups of IDA and the oxoanions in the neutral pH shown in 30 wt% H(2)O(2). When this method was applied to the selective separation of V(V), Mo(VI) and W(VI) from other metals in an acid soluble fraction of fly-ash, 83.4 ± 2.5% of V(V), 88.1 ± 3.3% of Mo(VI), and 69.3 ± 5.4% of W(VI) were recovered in a 30 wt% H(2)O(2) eluent.

Aims: Research has focused on treatment of overactive bladder (OAB) symptoms in women with the goal of cure. The objective of this study was to assess women's perceptions of their OAB symptoms, treatment experience, and outcomes by conducting patient focus groups., Methods: Women seen in our academic center female urology referral clinics were identified by ICD-9 codes for OAB symptoms and recruited to participate in one of five focus groups, totaling 33 patients. Non-clinician moderators conducted the focus group sessions incorporating topics related to patients' perceptions of OAB symptoms, treatments, and outcomes. Data analysis was performed using grounded theory methodology., Results: Qualitative analysis yielded several preliminary themes: impact of OAB on quality of life, strategies to control wetness, medications and side effects, and triggers. The majority of focus group participants reported only a partial response to medication and other physician-recommended treatments for OAB. Therefore, they developed self-reliant personalized strategies to improve their quality of life. These strategies included fluid restriction, preventive toileting, and, most importantly, the use of incontinence pads., Conclusions: The majority of the women who participated in the focus groups reported only a partial response to medical and other treatments for OAB. As a result, they developed personalized self-management strategies to improve their quality of life. Although most studies addressing the treatment of OAB aim at curing the condition, such a strategy may be unrealistic. Applying a chronic care model that uses a patient-centered symptom-management approach to OAB may optimize patient outcomes and improve quality of life., (Copyright © 2011 Wiley-Liss, Inc.)

Objectives: To better understand aging women's experience with overactive bladder (OAB) symptoms and the care they receive, with the ultimate goal of improving the quality of care provided to aging women with overactive bladder., Methods: Women seen in outpatient female urology clinics were identified by ICD-9 codes for OAB and recruited. Patients with painful bladder syndrome, mixed stress and urge incontinence, prolapse, or recent pelvic surgery were excluded. Patient focus groups were conducted by trained nonclinician moderators incorporating topics related to patients' perceptions of OAB physiology, symptoms, diagnostic evaluation, treatments, and outcomes. Qualitative data analysis was performed using grounded theory methodology., Results: Five focus groups totaling 33 women with OAB were conducted. Average patient age was 67 years (range, 39-91). Older women with OAB lacked knowledge about the physiology of their disease and had poor understanding regarding the rationale for many diagnostic tests, including urodynamics and cystoscopy. The results of diagnostic studies often were not understood by older patients. Many women were dissatisfied with the care they had received. This lack of knowledge and understanding was more apparent among the elderly women in the group., Conclusions: Findings demonstrated a poor understanding of the physiology of overactive bladder and the rationale for various diagnostic modalities and treatments. This was associated with dissatisfaction with care. There is a need for better communication with older women experiencing OAB symptoms about the physiology of the condition., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Airborne particulate matter (PM) collected in Bucharest (Romania) and Tokushima (Japan) was comprehensively characterized through multielemental analysis by ICP-MS to the PM samples. Prior to an elemental characterization of the sample, a multielemental determination method composed of acid digestion (HClO(4)/HNO(3)/HF or H(2)O(2)/HNO(3)/HF) and inductively coupled plasma mass spectrometry/inductively coupled plasma atomic emission spectrometry (ICP-MS/ICP-AES) was established to analyze a certified reference material of vehicle exhaust matter (NIES No. 8) for verifying the method. As the results, 39 elements in the certified reference material could be determined. They were a good agreement with the certified and reference values for HClO(4)/HNO(3)/HF acid digestion. Chalcophile elements, such as cadmium, antimony, and lead in Bucharest showed higher enrichment factors than those in Tokushima.

Most carcinomas spread to distant sites through lymphatic vessels. Several preclinical and clinical studies have shown a positive correlation between the incidence of lymph node metastasis and secretion of the lymphatic growth factor vascular endothelial growth factor-C (VEGF-C) by tumor cells, suggesting tumor lymphangiogenesis as an escape mechanism. However, recent evidence has shown VEGF receptor-3 (VEGFR-3) expression on tumor cells and autocrine signaling, which increase metastatic potential. Furthermore, there is growing evidence implicating lymphatic-homing chemokine receptors, particularly C-C chemokine receptor 7 (CCR7), in lymph node metastasis. We report here that expressions of VEGF-C and CCR7 by tumor cells act synergistically to promote their invasion toward lymphatics. First, VEGF-C acts to increase lymphatic secretion of CCL21, which in turn drives CCR7-dependent tumor chemoinvasion toward lymphatics. Second, VEGF-C acts in an autocrine fashion to increase tumor invasiveness by increasing the proteolytic activity and motility of tumor cells in a three-dimensional matrix. Both of these effects are VEGFR-3 dependent and evident only in three-dimensional environments. We further verified that VEGF-C induces lymphatic CCL21 up-regulation in vivo by direct injection of VEGF-C protein intradermally in the mouse. Taken together, these results bridge the prometastatic functions of CCR7 and VEGF-C in tumors and show that, beyond lymphangiogenesis, VEGF-C promotes tumor invasion toward lymphatics by both autocrine and CCR7-dependent paracrine signaling mechanisms, which may be a significant cause of lymph node metastasis.

Guided by structure-based design, we synthesized two novel series of potent inhibitors of BACE1 and generated extensive SAR around both the prime and non-prime side binding pockets. The key feature of both series is a cyclic amine motif specifically crafted to achieve interactions with both the flap and with the S2' pocket.

A patient underwent radiofrequency (RF) ablation of a pleural-based pulmonary metastasis from treated hepatocellular carcinoma. Ten months after the procedure, computed tomography and positron emission tomography findings raised the concern of tumor recurrence with invasion of the chest wall, for which the patient underwent thoracotomy with resection. Pathologic evaluation demonstrated osteonecrosis of the rib but no malignancy. This case illustrates that thermal osteonecrosis may occur after RF ablation of a pleural-based lesion.

Shrimp farming is a sufficiently large and mature industry to have an effective range of antimicrobial agents for most bacterial diseases in shrimp culture. However, at present, there exists great concern over the widespread use of antibiotics in aquaculture, which may result in residue of antibiotics in water and mud, and subsequently, the development of antibiotic resistance in bacteria in the environment. There is limited understanding about the effect of antibiotic residues on bacteria resistance in shrimp farming environment. Therefore, a study was conducted to investigate bacterial resistance to Norfloxacin (NFXC), Oxolinic Acid (OXLA), Trimethoprim (TMP) and Sulfamethoxazole (SMX), which were found in four shrimp farming locations in mangrove areas in Vietnam. Findings indicate that there is a relatively high incidence of bacteria resistance to these antibiotics observed in most of the studied sites, particularly to antibiotics with concentration of 0.1 microg/ml. Yet the relation between concentration of antibiotic residues and incidence of antibiotic resistance is not clearly defined. Among individual antibiotics, the incidence of resistance to TMP and SMX was higher than the others. Identification of bacteria isolated from mud samples by DNA analyzer shows that Bacillus and Vibrio are predominant among bacteria resistant to the antibiotics. The result of the study also indicates that these antibiotics in media degraded more rapidly due to the presence of resistant bacteria.

Vascular endothelial growth factor (VEGF)-C is necessary for lymphangiogenesis and holds potential for lymphangiogenic therapy in diseases lacking adequate lymphatic drainage. However, the ability of VEGF-C to enhance sustainable, functional lymphatic growth in adult tissues remains unclear. To address this, we evaluated VEGF-C overexpression in adult lymphangiogenesis in regenerating skin. We used a model of mouse tail skin regeneration incorporating a suspension of either VEGF-C overexpressing tumor cells, which provide a continuous supplement of excess VEGF-C to the natural regenerating environment for more than 25 days, or otherwise identical control-transfected tumor cells. We found that excess VEGF-C did not enhance the rate of lymphatic endothelial cell (LEC) migration, the density of lymphatic vessels, or the rate of functionality -- even though lymphatic hyperplasia was present early on. Furthermore, the hyperplasia disappeared when VEGF-C levels diminished, which occurred after 25 days, rendering the lymphatics indistinguishable from those in control groups. In vitro, we showed that whereas cell-derived VEGF-C could induce chemoattraction of LECs across a membrane (which involves amoeboid-like transmigration), it did not increase LEC chemoinvasion within a 3-dimensional fibrin matrix (which requires proteolytic migration). These results suggest that whereas excess VEGF-C may enhance early LEC proliferation and cause lymphatic vessel hyperplasia, it does not augment the physiological rate of migration or functionality, and by itself cannot sustain any lasting effects on lymphatic size, density, or organization in regenerating adult skin.

In recent years, antibiotics have been used widely in intensive shrimp culture and this may lead to their contamination of the environment. Surveys on residues of trimethoprim (TMP), sulfamethoxazole (SMX), norfloxacin (NFXC) and oxolinic acid (OXLA) in water and mud in shrimp ponds in mangrove areas were conducted in the north as well as in south of Viet Nam in July and August, 2002. The results show that these antibiotics are found in all samples in both shrimp ponds and surrounding canals. The highest concentrations of TMP, SMX, NFXC and OXLA are 1.04, 2.39, 6.06, and 2.50 ppm in water samples; and 734.61, 820.49, 2615.96, 426.31 ppm (based on wet mud weight), respectively. The comparison of antibiotics residues between study sites and types of shrimp ponds will be discussed in this paper. The results also suggest that antibiotics residues may cause harmful effect on ecosystems in the study sites.

Salmonella has developed ways to modulate host cellular response in order to survive. Although the steps required for such modulation have been incompletely characterized, there is increasing evidence for a role for SptP, a type III secretion protein. In part, the actions of SptP are thought to be mediated through its reported inhibition of the extracellular-regulated kinase (ERK) MAP kinase pathway. In the present studies, a series of transfections were performed in which various constitutively activated components of the MAP kinase pathway were co-transfected with SptP in order to determine the mechanism by which SptP inhibits this MAP kinase activation. SptP was found to inhibit the activation of ERK stimulated by both a constitutively active form of Ras and a partially activated form of Raf-1 containing a phospho-mimetic mutation (Raf Y340D). In contrast, the activation of ERK by constitutively active forms of MAP kinase kinase (MEK) was not inhibited, suggesting that the actions of SptP were mediated by Raf-1. In order to determine how SptP might interfere with activation of Raf, we utilized a membrane-localized form of Raf. Constitutive membrane-localization of Raf (RafCAAX), resulting in partial activation, did not prevent inhibition by SptP. However, introduction of an additional, partially activating (Y340D) phospho-mimetic mutation, to RafCAAX, dramatically reduced the ability of SptP to inhibit Raf action. Comparison of SptP mutants, lacking either GTPase-activating protein (GAP) activity or tyrosine phosphatase activity, further suggested that SptP inhibits both the membrane localization and subsequent phosphorylation required for activation of Raf. Both tyrosine phosphatase activity and GAP activity were responsible for SptP inhibition of Raf(Y340D)-induced ERK activation, but only GAP activity was responsible for inhibition of the membrane localized forms of Raf-1. To assess the biological significance of SptP, we examined tumour necrosis factor (TNF)-alpha induction following Salmonella infection. SptP gene deletion enhanced the capacity of Salmonella to induce TNF-alpha secretion following infection of J774A.1 macrophage cells.

Bioassay-directed fractionation led to the isolation of 14 compounds, six of which possess antimalarial activity, from the dried leaves and stems of Rhaphidophora decursiva. Polysyphorin (1) and rhaphidecurperoxin (6) showed strong activities against Plasmodium falciparum. Rhaphidecursinol A (2), rhaphidecursinol B (3), grandisin (4), and epigrandisin (5) were less active against the same organism. Among the isolates, rhaphidecursinol A (2) and rhaphidecursinol B (3) were determined to be new neolignans, and rhaphidecurperoxin (6) is a new benzoperoxide. Known compounds isolated include polysyphorin (1), grandisin (4), epigrandisin (5), (+)-medioresinol, (-)-pinoresinol, (-)-syringaresinol, (+)-glaberide I, (+)-dehydrovomifoliol, (-)-liliolide, (-)-hydroxydihydrobovolide, and N-butylbenzamide, of which compound 1 appears worthy of further evaluation as an antimalarial agent. Structure elucidation and identification were accomplished by spectroscopic means including 1D and 2D NMR analyses.

The pregnane steroid, (E)-aglawone, along with four known triterpenes, and a known sterol mixture were isolated from the bark of Aglaia lawii (Wight) Saldanha ex Ramamoorty (Meliaceae). The structural determination/identification was accomplished by a combination of 1D- and 2D-NMR spectroscopic techniques. The relative stereochemistry of the known triterpene, 20S,24S-epoxydammarane-3alpha,25-diol acetate, was also unequivocally determined for the first time by X-ray crystallography. The isolates were not active against various human cancer cell lines.

To investigate the distribution of Gnathostoma spp in Ho Chi Minh City (HCM city), 1,081 eels were purchased from a local market twice a month from March 1998 to February 1999. Infective larvae of Gnathostoma spp detected from the flesh and liver of eels by the press preparation technique were examined and identified. Three hundred and fifty advanced third-stage larvae were recovered from liver, none from the flesh. The average rate of infection was 0.11; a high rate of infection was found from August to November and a low rate of infection from February to May. The average number of larvae/eel was 2.9; the greatest number of larvae/eel was in January whereas the lowest was in March and April. There was a marked decrease in both prevalence and intensity of infection from February to May, followed by a rise from June. The finding suggests that in HCM city, the infection rate abruptly decreases soon after the end of the rainy season and starts to rise when the rain comes and reaches its peak at the end of the rainy season. All recovered larvae were identified as G. spinigerum.