Volume 7 (2013): Issue 4 (August 2013)

Background: Small interfering RNA (siRNA) has attracted extensive attention showing significant promise for the study, diagnosis, and treatment of human disease. However, the specific and efficient delivery of siRNA into cells in vivo remains a great challenge. Targeted modification of siRNA, viral nanoparticle-based vectors, targeted multifunctional/multistage nanosystems, combining ultrasound-targeted microbubble destruction, and tumor targeting in an all-in-one system, provides a useful multimodal approach in targeted delivery.

Objective: We provided an overview of different strategies for siRNA delivery including direct modification of siRNA, nanoparticles and viral vectors.

Methods: We conducted a search of standard database. Relevant primary and summary resources were identified and abstracted. A summary of strategies for in vivo targeted gene silencing was produced.

Results: A list of strategies for gene-targeted delivery in vivo was summarized, including target cells, target genes, target legends, and disease model for each strategy. An overview of strategies for siRNA delivery aimed at in vivo targeted gene silencing was presented.

Conclusions: Integration of the advantages of viral or nonviral vectors into gene silencing could have profound impacts on biomedical research. Recent progress is pointing at answers.

Background: Previous studies have demonstrated that grapefruit juice increased the bioavailability of cyclosporine; however, the results from the literature are inconsistent. Other citrus fruits such as pomelo or orange juice had variable effects on the bioavailability of cyclosporine.

Objective: To assess the effect of grapefruit juice and other types of citrus juice on oral bioavailability of cyclosporine in humans using meta-analysis.

Methods: We conducted a meta-analysis of placebo-controlled studies evaluating the effects of citrus juices on bioavailability of cyclosporine. The studies were identified in PubMed, Cochrane CENTRAL, CINAHL, ISI Web of Knowledge, Psych Info International, Pharmaceutical Abstract (IPA), and reference lists of relevant papers. The weighted-mean difference (WMD) was calculated for net changes in the area under the curve (AUC) of cyclosporine. All studies conducted as placebo-controlled crossover studies in humans to compare the effect of citrus juices and control (drinking water) on AUC of cyclosporine and/or Cmin,ss were reviewed. All studies included were evaluated and extracted independently, and discrepancies were resolved through discussion.

Results: Eighteen studies were identified. A subgroup analysis suggested that grapefruit juice significantly increased AUC of cyclosporine (WMD = 1762.5 ng⋅h/ml, 95%CI = 1178.9-2346.0 ng⋅h/ml, p < 0.001). While a meta-analysis of all other types of citrus juices (tangerine juice, Seville orange juice, sweet orange juice, and citrus soda) except pomelo juice revealed no effect on the AUC of cyclosporine (WMD = -181.0 ng⋅h/ml, 95%CI = -582.8-220.9 ng⋅h/ml, p > 0.5), a study of pomelo juice indicated a significant increase in the AUC of cyclosporine.

Conclusions: Grapefruit juice intake increases oral bioavailability of cyclosporine in both healthy volunteers and renal transplant patients, whereas all other types of citrus juices may not have an influence on the oral bioavailability of cyclosporine. Current evidence suggests that pomelo juice may be able to increase cyclosporine oral bioavailability.

Background: Water is a valuable resource in Saudi Arabia. There are untreated wells scattered throughout villages that are sources of drinking water for some rural residents.

Objectives: The present study was conducted to assess the quality of bottled and tap water as well as water from wells in the rural areas of Riyadh, Saudi Arabia.

Material and Methods: Water samples (n = 300) were randomly collected from bottles, taps, and wells. Bacteriological examination of samples included total and fecal coliforms. Screening was performed using wet mounts, trichrome stain, and a modified Ziehl-Neelsen technique. Total dissolved salts (TDS) were determined using a conductivity meter.

Results: There were no coliforms in samples taken from bottled water, whereas, they were detected in samples taken from tap and well water with percentages of 11%, 30% respectively (p = 0.0001). No fecal coliforms were detected in any of the bottled water samples. However, they were isolated from tap (7%) and well water samples (22%), p = 0.001. Escherichia coli content was found to have the highest percentage distribution compared with other coliforms subtypes in both tap and well water. Parasitological analysis detected only few cysts of Entameba coli in both tap (3%) and well (4%) samples while Giardia lamblia cysts (2%) were only detected in well water. There was a wide variation in concentrations of TDS in the 300 water samples. Chemical analysis of well water showed levels above the maximum limits of Saudi and international recommended standards and guidelines for salinity of drinking water.

Conclusion: Water derived from wells in rural areas of Riyadh showed microbial contamination and high total dissolved solids.

Background: Management of perihilar cholangiocarcinoma is mainly by surgery. Computed tomography is the imaging choice by which to evaluate tumor extension and resectability. However, reports concerning the accuracy of computed tomography for this purpose differ.

Objective: To retrospectively assess the accuracy of 16-detector-row computed tomography in evaluating tumor extension and tumor resectability of perihilar cholangiocarcinoma.

Method: Sixty-two patients attending our hospital from January 2004 to June 2011were included in this study. Tumor extension and resectability were retrospectively reviewed. Pathological results, diagnostic laparoscopy, and surgical findings were used as references.

Result: The accuracy for predictability of resectability was 80.7%. The accuracy of 16-detector-row computed tomography in evaluating tumor extension was; 95.2% for prediction of ductal involvement, 85.7% for prediction of hepatic artery invasion, 79.1% for prediction of portal vein invasion, 67.3% for prediction of N1 nodal involvement and 90.9% for prediction of N2 nodal involvement.

Conclusion: Good accuracy was found using 16-detector-row computed tomography in overall evaluation of tumor resectability. For tumor extension, 16-detector-row computed tomography has good accuracy except for evaluating N1 nodes.

Background: Fiducial markers are objects placed in the field of view of an imaging system for use as a point of reference or a measure. There is no information regarding suitable markers for joint models.

Objectives: We compared the fiducial markers commonly used in X-ray, CT, and MRI imaging modalities.

Methods: The markers tested were plastic balls, ceramic balls, passive reflective balls, liquid-filled balls, and steel balls. The balls were scanned using X-ray, CT, and MRI systems. The scanned X-ray images were reviewed if it the markers are able to be expressed. The tomographic images of CT and MRI were converted into 3D ball models and then the reconstructed shapes and dimensions of the balls were examined. The dimensional accuracy of expression and reconstruction was calculated in terms of the mean and the standard deviation.

Results: There was no marker that can be expressed in all the imaging modalities. Alternatively, we propose a synthetic marker that is composed of a hard sphere and a fat tissue wrapping. The hard ball is for X-ray and CT imaging, while the fat tissue is for MRI imaging.

Conclusion: A synthetic marker composed of a hard sphere and a fat tissue wrapping can a multimodal fiducial marker.

Background: Pregnancy-associated plasma protein A (PAPP-A) is a potentially proatherosclerotic metalloproteinase, which has been shown to be abundantly expressed in ruptured unstable plaques. However, changes of the PAPP-A blood levels in patients with coronary artery disease (CAD) according to the Gensini score is unknown in Turkish population.

Objective: We hypothesized that pregnancy-associated plasma protein A (PAPP-A) levels might be important in determining the degree of CAD severity and extent according to its relationship with inflammation in the partly unstable plaque area and with proliferative stimulation overall.

Methods: Our study population included 145 consecutive patients, who underwent elective diagnostic coronary angiography because of CAD symptoms such as chest pain or shortness of breath. The severity and the extent of CAD were evaluated using the Gensini score. Plasma PAPP-A concentrations were determined by ELISA.

Results: Among the 145 study patients (mean age 57 ± 10 years; 97 men and 48 women), 80 had mild CAD (Gensini score <20, group 1), 65 had severe CAD (Gensini score ≥ 20, group 2). PAPP-A levels were significantly higher in group 2 than they were in group 1 (2.7 ± 2.7 μg/ml vs. 1.12 ± 1.3 μg/ml, p < 0.001, respectively). PAPPA levels revealed a moderately positive linear correlation with Gensini scores (r = 0.435; p < 0.001). In addition, there was a weak, but still a positive correlation between PAPP-A levels and age (r = 0.174; p = 0.03).

Conclusion: There is still a need for large epidemiological studies to better understand the mechanisms and prognostic roles of both PAPP-A and insulin-like growth factor 1 in asymptomatic subjects and in subjects with well-documented CAD. If the results were promising, the measurement of PAPP-A may become a clinically important tool for risk stratification in patients with chest pain.

Background: Blowflies (order: Diptera, family: Calliphoridae) and house flies (order: Diptera, family: Muscidae) are important indicators to determine postmortem intervals in forensic entomology. Knowledge of the ecology and bionomics of individual species is necessary for the use of these flies as forensic indicators. Baited trapping is often employed to collect flies for such studies. However, the effect of baits on the diversity and abundance of baited trap collections is not known.

Objective: To compare the sampling effectiveness of several types of bait in terms of diversity and abundance of forensically important flies.

Materials and methods: The effectiveness of belacan (fermented shrimp paste), sugar, beef, ox liver, and fish were tested in three locations at different altitudes in Malaysia; Gombak Field Study Station (about 200 m above sea level (a.s.l.); N3°19′28″, E101°45′09″), Awana (about 1100 m a.s.l.; N3°24′03″ E101°46′59″) and Bukit Cincin (about 1700 m a.s.l.; N3°25′58″ E101°47′05″).

Results: Fish consistently attracted more flies and species than other baits. Beef and ox liver produced moderate or inconsistent results. Flies were rarely attracted to preserved baits such as shrimp paste or odorless baits such as sugar. At higher elevations, flies were attracted to a wider variety of baits. Meat may cause a bias towards mated gravid females and produce a biased sample of the true population.

Conclusion: Fish produced the most consistent results in terms of highest number of flies collected and wide diversity of species sampled, odor, especially from rotting meat, is important in attracting carrion flies.

Background: Despite important advances in the diagnosis and treatment of acute pulmonary embolism (APE), diagnosis of pulmonary embolism (PE) is difficult in patients with chronic obstructive pulmonary disease (COPD) and exacerbation.

Objective: We evaluated PE in patients with chronic obstructive pulmonary disease and exacerbations of unknown origin.

Methods: Two-hundred and eight patients with COPD and severe exacerbations were studied. All patients had CT pulmonary angiography (CTPA) and lower limb ultrasonography. Arterial blood gas measurements, D-dimers and endothelin-1 (ET-1) levels were recorded.

Results: The frequency of PE was 33%. The following were more common in the PE group (χ² = 4.32-6.79, mean p < 0.05): immobilization ≥ 7 days; a ≥ 1 cm difference in edema of the lower limbs; deep venous thrombosis; syncope; S1Q3T3 syndrome; and a decrease in PaCO₂ ≥ 5 mm Hg. Plasma D-dimers and ET-1 levels were significantly higher in the PE group. Risk factors identified from logistic regression analysis were immobilization ≥ 7 days, ≥ 1 cm difference in lower limb edema, and deep venous thrombosis.

Conclusions: Overall, 33% of 208 patients had a PE, and the risk was greater in those who had been immobilized, those who had a ≥ 1 cm difference in edema of the lower limbs, and those who had a deep venous thrombosis.

Background: Aripiprazole, a second-generation antipsychotic, has been shown to have short- and long term efficacy in bipolar disorder as monotherapy and in two-drug combinations. However, its long-term effectiveness among patients with different degrees of pharmacotherapeutic complexity and baseline mood disturbances is not known.

Objective: To assess long-term aripiprazole effectiveness in bipolar disorder (BD) patients in relationship to pharmacotherapeutic complexity and degree of baseline mood disturbance.

Methods: Outpatients assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation, and monitored with the STEP-BD Clinical Monitoring Form received open-label aripiprazole.

Results: Ninety-seven patients (52 BDI, 40 BDII, 5 BD NOS, mean age 40.2 years, 75.3% female) received aripiprazole combined with a mean ± SD (median) of 2.9 ± 1.7 (3) other prescription psychotropics, with 39.2% (38/97) receiving up to triple-pharmacotherapy (aripiprazole plus up to 2 other psychotropics) and 60.8% (59/97) taking quadruple-or-more-pharmacotherapy (aripiprazole plus at least 3 other psychotropics). At baseline 71.1% (69/97) of patients were symptomatic and 28.9% (28/97) were euthymic. Overall, mean (median) aripiprazole final dose and duration were 17.6 (15) mg/day and 388 (190) days, respectively. Aripiprazole was discontinued in only one-quarter of euthymic patients taking up to triple-pharmacotherapy, but in two-thirds of other patients (symptomatic patients taking up to triple-pharmacotherapy and symptomatic/euthymic patients taking quadrupleor- more-pharmacotherapy).

Conclusion: Aripiprazole treatment of bipolar disorder may be modestly extended beyond mono-pharmacotherapy and dual-pharmacotherapy to include triple-pharmacotherapy in euthymic patients, but further extension beyond current indications may not be effective in most patients.

Background: Pelvic ultrasonography is necessary for the diagnosis of polycystic ovary syndrome (PCOS). Compared with transabdominal ultrasonography, a transvaginal approach provides better endometrial imaging, but is more invasive. A thick endometrium is associated with endometrial abnormalities indicating further surveillance.

Objectives: We determined factors associating with endometrial thickness in PCOS Thai women. The information is useful to identify patients who need endometrial surveillance.

Methods: One hundred sixty-nine Thai women with PCOS diagnosed using revised Rotterdam 2003 criteria were examined for weight, height, waist circumference, and signs of hyperandrogenism. Endometrial thickness was determined by ultrasonography. Venous blood samples were collected after 12-hour fasting period and at 2 hours after 75-gram oral glucose loading.

Results: Endometrial thickness had moderate correlation with BMI (r = 0.207, p = 0.007), 2-hour glucose (r = 0.227, p = 0.003), and serum total testosterone (r = -0.278, p < 0.001); it had weak to null correlation (r < 0.2) with age, duration of amenorrhea, waist circumference, Ferriman-Gallwey score, and other parameters of insulin resistance and hyperandrogenemia. Multiple logistic regression analysis demonstrated that important factors associating with endometrial thickness ≥7 mm were total testosterone >0.8 ng/mL (OR = 0.241, 95%CI 0.118-0.493, p < 0.001) and BMI >23.5 kg/m² (OR = 2.431, 95%CI.1.196-4.939, p = 0.014).

Conclusions: Endometrial thickness in PCOS Thai women has significantly inverse correlation with serum total testosterone and positive correlation with BMI. Endometrial thickness measurement using transvaginal ultrasonography may be unnecessary for PCOS Thai women with hyperandrogenism.

Background: Many athletes, especially at elite university level, suffer from chronic ankle instability (CAI). Chronic ankle instability usually occurs after simple ankle sprain from poor landing. The repetitive injury causes chronic ankle instability. This chronic ankle instability leads to poor performance and recurrent injury during training and competition. A proper rehabilitation program may improve performance and prevent further injury.

Objectives: We aimed to compare the effect of a 6-week functional rehabilitation program in athletes with chronic ankle instability between a hydrotherapy plus ankle taping group and a land-based plus ankle taping group on ankle functional ability, ankle joint position sense and the number of reinjuries.

Methods: Forty-seven university level athletes with chronic ankle instability and residual symptoms were randomized into a hydrotherapy group (24 participants) and a land-based group (23 participants). All participants were taped using a heel lock technique at the injured ankle during the training session. The rehabilitation program included stretching, aerobic exercise, balance exercise, strengthening exercise, and skill training using an aquatic or land-based environment according to the group for 6 weeks. A single-limb hopping test and ankle joint position sense were measured at baseline, 6 weeks, and 3 months. Recurrent ankle injuries were also recorded.

Results: In the hydrotherapy group, the time taken in the single-limb hopping test significantly decreased immediately after exercise and at the follow up compared with baseline (p = 0.001). In the land-based group, time taken in the single-limb hopping test significantly decreased at 3 months follow up compared with baseline (p = 0.05). No significant differences were detected between groups in ankle joint position sense and the number of recurrent ankle sprains. All participants returned to their athletic activity and competition.

Conclusion: The combined rehabilitation program of ankle taping, land-based exercise and/or hydrotherapy could be recommended for clinical uses in athletes with chronic ankle instability.

Background: Epidemiological data of dengue patients in Ratchaburi, Thailand have been reviewed from the year 2000 through 2010. However, with the changes in population structure and lifestyle, a more detailed analysis is needed.

Objective: We described the changes in the epidemiology of dengue patients in Ratchaburi province, Thailand.

Materials and Method: Cases of dengue patients reported by Ratchaburi Provincial Office, Ministry of Public Health, Thailand.

Result: During the years 2000 to 2010, the rate of dengue patients in Ratchaburi, Thailand varied from 123.45 per 100,000 population in 2003 to 394.25 per 100,000 population in 2008. The case fatality rate varied from 0-0.62%. The disease was seen all year round with a higher incidence in the rainy season. Although the highest attack rate has been observed amongst children below 15 years old, a trend of shift in age group towards older children and adults has been seen during the past decade.

Conclusion: Dengue patients are common in Ratchaburi, Thailand causing heavy burden on the health system. The case fatality rate was between 0-0.62% throughout the period of study indicating early recognition and improved management of dengue patients. The trend towards higher age in dengue patients during the past decade is a problem of concern and needs further clarification.

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an enzymopathy with high frequency in Southeast Asians. Phuan is a minority tribe in Thailand. The prevalence of G6PD deficiency and its molecular heterogeneity in this population is yet unknown.

Objectives: To characterize molecular heterogeneity of G6PD in Phuan people and investigate whether the heterogeneity of G6PD could be used to delineate the origin of Phuan people in Thailand.

Methods: Cord blood samples from 202 Phuan neonates were tested for G6PD deficiency using a G6PD activity assay. G6PD mutations were determined in G6PD deficient blood samples by polymerase chain reaction-restriction fragment length polymorphism analysis and sequencing.

Results: G6PD deficiency was found in 12 (12.2%) of 98 males and 8 (7.7%) of 104 females in the study population. Molecular analysis was performed on 12 males and 8 females to identify G6PD mutations. G6PD Viangchan (871G→A, 1311C→T)(25.0%) was the most dominant mutation followed by the G6PD Canton (1376G→T) (15.0%), G6PD Union (1360C→T) (10.0%), one case each of G6PD Kaiping (1388G→A) and G6PD Mediterranean (563C→T, 1311C) (5%), and eight G6PD deficient unidentified mutations.

Conclusions: G6PD deficiency in Phuan is highly frequent and G6PD Viangchan(871G→A, 1311C→T) is the most common mutation. Our study suggests that Phuans have coevolved with Thais, and were influenced by gene flow from Chinese and Indian mutations.

Background: Low urinary excretion of citrate is a major risk in Thai kidney stone patients. Reabsorption of citrate at renal proximal tubules requires sodium-dicarboxylate cotransporter-1 (NaDC-1).

Objectives: We investigated the expression of NaDC-1 in stone-containing kidneys and evaluated the association of NaDC-1 expression with urine pH. Expression of NaDC-1 protein in acid-treated human proximal renal cells (HK-2 cells) was also studied.

Methods: Twenty-four patients with nephrolithiasis aged 50.61 ± 13.30 years (9 males, 15 females) were recruited. Twenty-four hours urine samples were collected from all patients. Expression of NaDC-1 in renal tissues and HK-2 cells was determined by immunohistochemistry and Western blotting, respectively.

Results: NaDC-1 was expressed mainly in proximal renal tubular cells. Tubular cells in the medullary region were weakly positive for NaDC-1. The intensity of NaDC-1 expression varied among nephrolithic renal tissues and was categorized into weak (6/24, 25%), intermediate (10/24, 42%), and high (8/24, 33%) expression. A trend of decreased urine pH in patients with increased NaDC-1 expression was observed. When the expression of NaDC-1 was recategorized into low (16/24) and high (8/24) expression, patients with high NaDC-1 expression had significantly lower urine pH than those with low NaDC-1 expression. Acid-treated HK-2 cells (pH 6.8) showed significantly higher expression of NaDC-1 compared with the control nontreated cells (pH 7.4). Significant association between urinary citrate and urine pH was not found. Also, significant association between urinary citrate and intrarenal NaDC-1 expression was not revealed.

Conclusion: NaDC-1 was principally expressed in proximal renal tubules of stone-bearing kidneys. High expression of NaDC-1 was associated with low urine pH. To our knowledge, this is the first report of NaDC-1 expression in the kidneys of nephrolithiasis patients. We experimentally confirmed that acid conditions upregulated the expression of NaDC-1 in the human proximal tubular cells.

Background: Although spinal anesthesia with intrathecal morphine is considered to be an alternative technique for analgesia after total knee arthroplasty (TKA), it is simple, easy to perform, and economical. Information to improve postoperative outcome of intrathecal morphine for TKA is still limited.

Objective: To investigate whether preoperative combination of pregabalin and celecoxib is superior to either drug alone to improve the analgesic efficacy of intrathecal morphine for patients after TKA.

Methods: A randomized, placebo-controlled, double-blind trial of pregabalin (150 mg), celecoxib (400 mg), or in combination, administered before TKA. All patients received spinal anesthesia with intrathecal morphine 0.2 mg and patient-controlled analgesic morphine postoperatively. The primary outcome was 24 hours cumulative morphine consumption. Secondary outcomes included time to first dose of morphine, 0-10 Visual Analog Scale (VAS) of pain scores at rest and when moving, VAS anxiety scores, patient satisfaction 0-10 score, postoperative adverse effects, and complications.

Results: One hundred patients were randomly assigned into four groups. There were no differences in the 24-h cumulative morphine consumption, time to first dose of morphine and in the results of the 24 hours of VAS pain scores at rest. Compared with the placebo group, pain scores when moving at 2 hours in the pregabalin-celecoxib group was significantly lower (p < 0.05). Significant decrease of anxiety scores were shown in the pregabalincelecoxib group at 2 hours and together with the celecoxib group at 6 hours and 24 hours postoperatively (p < 0.05). Postoperative adverse effects and complications were similar in all groups except for transcutaneous oxygen saturation (SpO₂) < 92% in the pregabalin group at the end of surgery. The patient satisfaction at 24 and 48 hours after surgery was similar in all groups.

Conclusion: Preoperative pregabalin, celecoxib alone, or as a combination does not improve the analgesic effect of 0.2 mg intrathecal morphine for patients after TKA. Although preoperative pregabalin with celecoxib may statistically decrease patients’ anxiety score for 24 hours postoperatively with comparable adverse effects, no clinical significance is observed

Background: Pyoderma gangrenosum is a rare condition usually associated with underlying diseases such as ulcerative colitis, inflammatory bowel disease, or rheumatoid arthritis. However, some cases may also be traced to trauma or surgical procedures.

Objective: We reported a patient with pyoderma gangrenosum from work-related injury with abnormal cytokine elevation.

Results: Skin biopsy of the ulcer showed diffuse cellular infiltration and increased expression of granulocyte colony-stimulating factor (G-CSF). Laboratory studies revealed elevated white blood cell levels and increases in the inflammatory markers interleukin-6 (IL-6) and G-CSF. Oral doses of prednisolone were effective in treating the ulcer.

Conclusion: Measuring G-CSF and IL-6 levels may help facilitate earlier diagnosis of pyoderma gangrenosum, thereby resulting in more effective treatment.