[Study on the protection of gingival epithelial barrier by interleukin-22 through regulating microbiota and E-cadherin expression].

Objective: To investigate the regulatory effect and mechanism of interleukin-22 (IL-22) on the gingival epithelial barrier in the context of periodontal inflammation. Methods: IL-22 knockout (IL-22 KO) mice were constructed, and periodontitis mice models were established through oral gavage with polymicrobial inoculation. DNAs were extracted from the oral plaques of IL-22 KO periodontitis mice group (n=7) and their wild-type littermates periodontitis group (n=7) to establish a periodontitis-related oral microbiota database"PD-RiskMicroDB", determining the relationship between changes in oral microbiota and microbial function in two groups using 16S rRNA sequencing results. Gingival epithelial cells (GEC) were cultured by modified trypsinization method, and were stimulated with 100 µg/L IL-22, Porphyromonas gingivalis (Pg) (multiplicity of infection:100), separately or together for 3 and 12 hours. The experimental groups were as follows: control group (no stimulation), IL-22 group, Pg group and Pg+IL-22 group. The expression of barrier protein E-cadherin in each group at 3 h was detected by immunofluorescence, real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting. Fluorescein isothiocyanate-dextran-mediated epithelial cell permeability experiment was conducted to clarify the changes in permeability of GEC in each group at 3 and 12 h. The mRNA expressions of E-cadherin in the gingival epithelium of wild-type littermates periodontitis group and IL-22 KO periodontitis group were detected by RT-qPCR. Fifteen C57BL/6 wild-type mice were randomly divided into control group (n=5), periodontitis group (n=5) and periodontitis+IL-22 treatment group (n=5). RT-qPCR and immunohistochemistry (IHC) staining were used to detect the expression level of E-cadherin in the gingival epithelium of each group. Results: 16S rRNA sequencing results showed that the composition of oral microbiota changed in IL-22 KO periodontitis group, of which the abundance of bacterial genera related to periodontal tissue invasion was significantly increased (linear discriminant analysis score: 2.22, P=0.009), compared with wild-type littermates periodontitis group. In vitro cell experiments showed that after Pg infection for 3 hours, the cell connections of GEC in Pg group were interrupted, and the fluorescence intensity of E-cadherin was reduced in Pg group compared with the control group. Meanwhile, the mRNA and protein expression levels of E-cadherin (mRNA: 0.69±0.12; protein: 0.60±0.12) were downregulated compared with the control group [mRNA: 1.00±0.00 (P=0.043); protein: 1.04±0.08 (P=0.003)], respectively. The fluorescence intensity of E-cadherin in the Pg+IL-22 group was enhanced compared with Pg group, and expression levels of E-cadherin mRNA (1.16±0.10) and protein (0.98±0.07) in Pg+IL-22 group showed a significant increase compared with Pg group [mRNA: 0.69±0.12 (P=0.005); protein: 0.60±0.12 (P=0.007)]. The result of epithelial permeability test showed that there was no statistical difference in epithelial permeability among control group, Pg group, IL-22 group and Pg+IL-22 group with treatment for 3 hours (F=0.20, P=0.893). While when the treatment time turned to be 12 hours, the epithelial barrier permeability showed a significant increase in Pg group (1.39±0.15) compared with control group (1.00±0.00, P=0.027), and a decrease in Pg+IL-22 group (1.02±0.18) compared with Pg group (1.39±0.15, P=0.034). In vivo, the mRNA expression of E-cadherin in the gingival epithelium of IL-22 KO periodontitis group decreased significantly (0.32±0.21) compared with wild-type littermates periodontitis group (1.01±0.01) (t=5.70, P=0.005). Moreover, RT-qPCR and IHC staining results showed that the mRNA expression level of E-cadherin (0.40±0.07) and absorbance value of E-cadherin positive expression (0.02±0.00) in gingival epithelial tissue of periodontitis group were both significantly down-regulated compared with control group [mRNA: 1.00±0.00 (P=0.005); absorbance value of E-cadherin positive expression: 0.04±0.01 (P=0.006)]. Meanwhile, the mRNA expression level of E-cadherin (1.06±0.24) and the absorbance value of E-cadherin positive expression (0.03±0.01) were both observed increase in periodontitis+IL-22 treatment group compared with periodontitis group (P=0.003, P=0.039). Conclusions: IL-22 may exert a protective effect on the gingival epithelial barrier in an inflammatory environment by regulating the invasiveness of oral microbiota and the expression of host barrier protein.

Presence of SARS-CoV-2-like coronaviruses in bats from east coast Malaysia.

Most of the public health importance coronaviruses, such as Severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2 are likely originated from bats and spread to humans through intermediate hosts; civet cats, dromedary camel and Malayan pangolin, respectively. SARS-CoV-2-like coronaviruses were detected in Thailand, which is neighbouring with Kelantan in East Coast Malaysia. To date, there is no report on the presence of public health concerns (SARS-CoV, SARS-CoV-2 and MERS-CoV) coronaviruses in bats from Malaysia. This study was aimed to elucidate the presence of these coronaviruses in bat samples from East Coast, Malaysia. A total of hundred seventy oropharyngeal swab samples were collected from three states of East Coast Malaysia. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was conducted based on partial 3' Untranslated region (3'UTR) or ORF10 gene and the products were sequenced. The sequences were compared with all coronavirus sequences from the National Center for Biotechnology Information-GenBank (NCBI-GenBank) using NCBI-Basic Local Alignment Search Tool (NCBI-BLAST) software. A phylogenetic tree was constructed to determine the genetic relationship among the detected coronaviruses with the reference coronaviruses from the NCBI-GenBank. Our results showed that SARSCoV-2-like viruses were present in 3% (5/170) of the bats from East Coast Malaysia that have 98-99% sequence identities and are genetically related to SARS-CoV-2 from humans. This finding indicates the presence of SARS-CoV-2-like viruses in bats from East Coast Malaysia that may become a public health concern in the future.

Presence of SARS-CoV-2-like coronaviruses in bats from east coast Malaysia

@#Most of the public health importance coronaviruses, such as Severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2 are likely originated from bats and spread to humans through intermediate hosts; civet cats, dromedary camel and Malayan pangolin, respectively. SARS-CoV-2-like coronaviruses were detected in Thailand, which is neighbouring with Kelantan in East Coast Malaysia. To date, there is no report on the presence of public health concerns (SARS-CoV, SARS-CoV-2 and MERS-CoV) coronaviruses in bats from Malaysia. This study was aimed to elucidate the presence of these coronaviruses in bat samples from East Coast, Malaysia. A total of hundred seventy oropharyngeal swab samples were collected from three states of East Coast Malaysia. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was conducted based on partial 3’ Untranslated region (3’UTR) or ORF10 gene and the products were sequenced. The sequences were compared with all coronavirus sequences from the National Center for Biotechnology Information-GenBank (NCBI-GenBank) using NCBI-Basic Local Alignment Search Tool (NCBI-BLAST) software. A phylogenetic tree was constructed to determine the genetic relationship among the detected coronaviruses with the reference coronaviruses from the NCBI-GenBank. Our results showed that SARSCoV-2-like viruses were present in 3% (5/170) of the bats from East Coast Malaysia that have 98-99% sequence identities and are genetically related to SARS-CoV-2 from humans. This finding indicates the presence of SARS-CoV-2-like viruses in bats from East Coast Malaysia that may become a public health concern in the future.

COVID-19: Four Paediatric Cases in Malaysia.

OBJECTIVE: This is a brief report of 4 paediatric cases of COVID-19 infection in Malaysia BACKGROUND: COVID-19, a coronavirus, first detected in Wuhan, China has now spread rapidly to over 60 countries and territories around the world, infecting more than 85000 individuals. As the case count amongst children is low, there is need to report COVID-19 in children to better understand the virus and the disease. CASES: In Malaysia, until end of February 2020, there were four COVID-19 paediatric cases with ages ranging from 20 months to 11 years. All four cases were likely to have contracted the virus in China. The children had no symptoms or mild flu-like illness. The cases were managed symptomatically. None required antiviral therapy. DISCUSSION: There were 2 major issues regarding the care of infected children. Firstly, the quarantine of an infected child with a parent who tested negative was an ethical dilemma. Secondly, oropharyngeal and nasal swabs in children were at risk of false negative results. These issues have implications for infection control. Consequently, there is a need for clearer guidelines for child quarantine and testing methods in the management of COVID-19 in children.

Prevalence of Toxoplasma gondii in pet and stray cats in Klang Valley, Malaysia.

Toxoplasma gondii, a zoonotic protozoan that has a worldwide distribution, is known to infect many warm-blooded vertebrates. The feline species including domestic cats are the definitive hosts for Toxoplama gondii and shed the infective oocyst. There is lack of information on the prevalence of Toxoplasma gondii in cats in Malaysia. The objective of this study was to determine both the seroprevalence of T. gondii and the prevalence of T. gondii DNA in cats' feces in Klang Valley, Malaysia. 198 blood and 201 fecal samples were collected from pet and stray cats from the local council, Dewan Bandaraya Kuala Lumpur (DBKL) and University Veterinary Hospital, Universiti Putra Malaysia respectively. The overall seroprevalence of Toxoplasma gondii in cats in the Klang Valley was found to be 5.5%. There was a high prevalence (10.5%) of T. gondii DNA detected in the cat fecal samples in both pet and stray cats suggestive of T. gondii oocyst shedding. Stray cats showed a higher seroprevalence and molecular prevalence of T. gondii than the pet cats. However, comparative analysis using Chi-square test showed no significant difference between both groups (P>0.05). Higher prevalence (10.5%) of cats shedding T. gondii DNA as compared to the seroprevalence (5.5%) was found in the cat population in the Klang Valley. The high prevalence of cats shedding T. gondii DNA is alarming as this may directly reflect the number of oocysts excreted into the environment posing a significant public health hazard.

First molecular detection of Tritrichomonas foetus in domestic cats in Klang Valley, Malaysia.

Tritrichomonas foetus is known to cause chronic diarrhea in the feline species in many different regions of the world. However, there is a paucity of information on T. foetus among cats in Malaysia. This study was conducted to determine the prevalence of Tritrichomonas foetus in the pet and stray cat population in Klang Valley, Malaysia. A total of 201 pet and stray cats' fecal samples were collected in Klang Valley. 24 samples were cultured in the InPouch® TF Feline to observe for motile trophozoites. A nested PCR protocol was used to screen for T. foetus in the collected samples. The prevalence of T. foetus in the cat population in Klang Valley was 33%. There was no association between Tritrichomonas infection and age, sex, breed or management of the cats. However, statistical analysis revealed that stray cats were more likely to be infected with T. foetus compared to pet cats. This study confirmed for the first time the presence of T. foetus among the cat population in Klang Valley, Malaysia.

First molecular detection of Tritrichomonas foetus in domestic cats in Klang Valley, Malaysia

@#Tritrichomonas foetus is known to cause chronic diarrhea in the feline species in many different regions of the world. However, there is a paucity of information on T. foetus among cats in Malaysia. This study was conducted to determine the prevalence of Tritrichomonas foetus in the pet and stray cat population in Klang Valley, Malaysia. A total of 201 pet and stray cats’ fecal samples were collected in Klang Valley. 24 samples were cultured in the InPouch® TF Feline to observe for motile trophozoites. A nested PCR protocol was used to screen for T. foetus in the collected samples. The prevalence of T. foetus in the cat population in Klang Valley was 33%. There was no association between Tritrichomonas infection and age, sex, breed or management of the cats. However, statistical analysis revealed that stray cats were more likely to be infected with T. foetus compared to pet cats. This study confirmed for the first time the presence of T. foetus among the cat population in Klang Valley, Malaysia.

Prevalence of Toxoplasma gondii in pet and stray cats in Klang Valley, Malaysia

@#Toxoplasma gondii, a zoonotic protozoan that has a worldwide distribution, is known to infect many warm-blooded vertebrates. The feline species including domestic cats are the definitive hosts for Toxoplama gondii and shed the infective oocyst. There is lack of information on the prevalence of Toxoplasma gondii in cats in Malaysia. The objective of this study was to determine both the seroprevalence of T. gondii and the prevalence of T. gondii DNA in cats’ feces in Klang Valley, Malaysia. 198 blood and 201 fecal samples were collected from pet and stray cats from the local council, Dewan Bandaraya Kuala Lumpur (DBKL) and University Veterinary Hospital, Universiti Putra Malaysia respectively. The overall seroprevalence of Toxoplasma gondii in cats in the Klang Valley was found to be 5.5%. There was a high prevalence (10.5%) of T. gondii DNA detected in the cat fecal samples in both pet and stray cats suggestive of T. gondii oocyst shedding. Stray cats showed a higher seroprevalence and molecular prevalence of T. gondii than the pet cats. However, comparative analysis using Chi-square test showed no significant difference between both groups (P>0.05). Higher prevalence (10.5%) of cats shedding T. gondii DNA as compared to the seroprevalence (5.5%) was found in the cat population in the Klang Valley. The high prevalence of cats shedding T. gondii DNA is alarming as this may directly reflect the number of oocysts excreted into the environment posing a significant public health hazard.

A colonic amoebic abscess mimicking colonic carcinoma.

Amebiasis is one of the major causes of diarrhea in the developing countries and it can present with a wide range of gastrointestinal symptoms depending on the phase of infection. We described a case of 50 year-old male patient who presented with abdominal pain, diarrhea and vomiting. After right hemicolectomy for appendicular abscess with tumour over the ileum, histopathological examinations revealed numerous trophozoites of Entamoeba histolytica in a background of inflammations (Figure 1). Following resection of the ameboma, he received intravenous metronidazole treatment for total of two weeks duration.

[The study of association of chronic rhinosinusitis inflammation subtype with bronchial inflammation phenotype].

Objective:We sought to compare clinical characteristics between eosinophilic and non-eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma, and explored the association of chronic rhinosinusitis inflammation subtypewith bronchial inflammation phenotype in CRSwNP with asthma. Method:Fifty-one consecutive patients suffering from CRSwNP with asthma undergoing endoscopic sinus surgery (ESS) were recruited. Preoperative computed tomography (CT), skin-prick test, bronchial provocation test, lung function, and oral fractional exhaled nitric oxide (FeNO) measurements were conducted. Venous blood was taken within 1 week before ESS. Nasal polyps (NPs) specimens were obtained from each patient during ESS, and stained with hematoxylin and eosin. According to the pathologic characteristics of NP samples, fifty-one patients suffering from CRSwNP with asthma were grouped as eosinophilic CRSwNP (ECRSwNP) and non-ECRSwNP and three levels of eosinophil infiltration were recognized. Result:Fifty-one patients suffering from CRSwNP with asthma were grouped as ECRSwNP (n=33) and non-ECRSwNP (n=18). History of surgery, history of allergy, Lund-Mackay scores, duration of asthma, frequency of severity asthma, numbers of asthma exacerbation in the last year, FeNO, blood eosinophil percentage and absolute count were all significantly higher in the ECRSwNP with asthma group compared with the non-ECRSwNP with asthma group (P<0.05). Blood eosinophil percentage had a significant correlation with degree of eosinophil infiltration in NPs (r=0.459, P<0.01) and FeNO (r=0.591, P<0.01). There was a correlation between degree of eosinophil infiltration in NPs and FeNO (r=0.556, P<0.01). Furthermore, Lund-Mackay scores had a positive correlation with blood eosinophil percentage (r=0.327, P<0.05) and degree of eosinophil infiltration in NPs (r=0.412, P<0.01) and FeNO (r=0.691, P<0.01). Conclusion:There is different clinical characteristics between ECRSwNP with asthma and non-ECRSwNP with asthma. These data suggest that CRSwNP inflammation subtype is significantly correlated with bronchial inflammation phenotype in patients suffering from CRSwNP with asthma.

Corrigendum to "Hodgkin Lymphoma Cell Lines Are Characterized by a Specific miRNA Expression Profile." Neoplasia 2009, Feb;11(2):167-176.

[This corrects the article DOI: 10.1593/neo.08980.].

Levels of Ancylostoma infections and phylogenetic analysis of cox 1 gene of A. ceylanicum in stray cat faecal samples from Guangzhou, China.

Ancylostoma ceylanicum is a common zoonotic nematode. Cats act as natural reservoirs of the hookworm and are involved in transmitting infection to humans, thus posing a potential risk to public health. The prevalence of feline A. ceylanicum in Guangzhou (South China) was surveyed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In total, 112 faecal samples were examined; 34.8% (39/112) and 43.8% (49/112) samples were positive with hookworms by microscopy and PCR method, respectively. Among them, 40.8% of samples harboured A. ceylanicum. Twelve positive A. ceylanicum samples were selected randomly and used for cox 1 sequence analysis. Sequencing results revealed that they had 97-99% similarity with A. ceylanicum cox 1 gene sequences deposited in GenBank. A phylogenetic tree showed that A. ceylanicum isolates were divided into two groups: one comprising four isolates from Guangzhou (South China), and the other comprising those from Malaysia, Cambodia and Guangzhou. In the latter group, all A. ceylanicum isolates from Guangzhou were clustered into a minor group again. The results indicate that the high prevalence of A. ceylanicum in stray cats in South China poses a potential risk of hookworm transmission from pet cats to humans, and that A. ceylanicum may be a species complex worldwide.

Development of a controlled release of salicylic acid loaded stearic acid-oleic acid nanoparticles in cream for topical delivery.

Lipid nanoparticles are colloidal carrier systems that have extensively been investigated for controlled drug delivery, cosmetic and pharmaceutical applications. In this work, a cost effective stearic acid-oleic acid nanoparticles (SONs) with high loading of salicylic acid, was prepared by melt emulsification method combined with ultrasonication technique. The physicochemical properties, thermal analysis and encapsulation efficiency of SONs were studied. TEM micrographs revealed that incorporation of oleic acid induces the formation of elongated spherical particles. This observation is in agreement with particle size analysis which also showed that the mean particle size of SONs varied with the amount of OA in the mixture but with no effect on their zeta potential values. Differential scanning calorimetry analysis showed that the SONs prepared in this method have lower crystallinity as compared to pure stearic acid. Different amount of oleic acid incorporated gave different degree of perturbation to the crystalline matrix of SONs and hence resulted in lower degrees of crystallinity, thereby improving their encapsulation efficiencies. The optimized SON was further incorporated in cream and its in vitro release study showed a gradual release for 24 hours, denoting the incorporation of salicylic acid in solid matrix of SON and prolonging the in vitro release.

Loss of TAK1 increases cell traction force in a ROS-dependent manner to drive epithelial-mesenchymal transition of cancer cells.

Epithelial-mesenchymal transition (EMT) is a crucial step in tumor progression, and the TGFß-SMAD signaling pathway as an inductor of EMT in many tumor types is well recognized. However, the role of non-canonical TGFß-TAK1 signaling in EMT remains unclear. Herein, we show that TAK1 deficiency drives metastatic skin squamous cell carcinoma earlier into EMT that is conditional on the elevated cellular ROS level. The expression of TAK1 is consistently reduced in invasive squamous cell carcinoma biopsies. Tumors derived from TAK1-deficient cells also exhibited pronounced invasive morphology. TAK1-deficient cancer cells adopt a more mesenchymal morphology characterized by higher number of focal adhesions, increase surface expression of integrin α5ß1 and active Rac1. Notably, these mutant cells exert an increased cell traction force, an early cellular response during TGFß1-induced EMT. The mRNA level of ZEB1 and SNAIL, transcription factors associated with mesenchymal phenotype is also upregulated in TAK1-deficient cancer cells compared with control cancer cells. We further show that TAK1 modulates Rac1 and RhoA GTPases activities via a redox-dependent downregulation of RhoA by Rac1, which involves the oxidative modification of low-molecular weight protein tyrosine phosphatase. Importantly, the treatment of TAK1-deficient cancer cells with Y27632, a selective inhibitor of Rho-associated protein kinase and antioxidant N-acetylcysteine augment and hinders EMT, respectively. Our findings suggest that a dysregulated balance in the activation of TGFß-TAK1 and TGFß-SMAD pathways is pivotal for TGFß1-induced EMT. Thus, TAK1 deficiency in metastatic cancer cells increases integrin:Rac-induced ROS, which negatively regulated Rho by LMW-PTP to accelerate EMT.

Association of HLA locus variant in Parkinson's disease.

A variant (rs3129882) in the genome-wide association study (GWAS)-linked variant [in the human leukocyte antigen (HLA) gene region] has been reported to associate with an increased risk of Parkinson's disease (PD) in Caucasian population. Studies among Chinese are limited. To address this, we analysed rs3129882 in a total of 1312 subjects of Chinese ethnicity from independent Asian centers comprising of 675 controls and 637 PD cases. The rs3129882 variant was associated with a decreased risk in our ethnic Chinese PD patients. Logistic regression analysis taking into consideration variables of age, gender and race showed that allele A reduced the risk of PD via a dominant model [odds ratio (OR) = 0.77, 95% confidence interval (CI) = 0.62, 0.96, p = 0.018]. As HLA is a highly polymorphic region, it is possible that ethnic-specific effect or environmental agents may modulate the effect of this GWAS-linked locus in influencing the risk of PD.

HLA variants rs9271366 and rs9275328 are associated with systemic lupus erythematosus susceptibility in Malays and Chinese.

BACKGROUND: Human leukocyte antigen (HLA) antigens and genes have long been reported associated with systemic lupus erythematosus (SLE) susceptibility in many populations. With the advance in technologies such as genome-wide association studies, many newly discovered SLE-associated single-nucleotide polymorphisms (SNPs) have been reported in recent years. These include HLA-DRB1/HLA-DQA1 rs9271366 and HLA-DQB1/HLA-DQA2 rs9275328. Our aim was to investigate these SNPs in a Malaysian SLE cohort. MATERIALS AND METHODS: SNPs rs9271366 and rs9275328 were screened across 790 Malaysian citizens from three ethnic groups (360 patients and 430 healthy volunteers) by Taqman SNP genotyping assays. Allele and genotyping frequencies, Hardy-Weinberg equilibrium, Fisher's exact test and odds ratio were calculated for each SNP and ethnic group. Linkage disequilibrium and interaction between the two SNPs were also evaluated. RESULTS: The minor allele G and its homozygous genotype GG of HLA-DRB1/HLA-DQA1 rs9271366 significantly increased the SLE susceptibility in Malaysian patients, including those of Malay and Chinese ethnicity (odds ratio (OR) > 1, p < 0.05). As for HLA-DQB1/HLA-DQA2 rs9275328, the minor allele T and the heterozygous genotype CT conferred protective effect to SLE in Malaysians, as well as in Malays and Chinese, by having OR < 1 and p value <0.05. Both SNPs did not show associations to SLE in Indians. D' and r (2) values for the two SNPs in LD analysis were 0.941 and 0.065, respectively, with haplotype GC and AT being significantly associated with SLE (p < 5.0 × 10(-4)) after 10,000 permutations were performed. The MDR test clustered the genotype combinations of GG and CC, and AG and CC of rs9271366 and rs9275328, accordingly, as high-risk group, and the two SNPs interacted redundantly by removing 1.96% of the entropy. CONCLUSIONS: Our findings suggest that in addition to some classical HLA variants, rs9271366 and rs9275328 are additional polymorphisms worth considering in the Malaysian and possibly in a larger Asian SLE scenario.

Penicilliosis in lupus patients presenting with unresolved fever: a report of 2 cases and literature review.

Penicilliosis is a rare occurrence among non human immunodeficiency virus (HIV) infected patients. We report here two cases of Penicillium marneffei infection in patients with systemic lupus erythematosus (SLE). Both patients had a recent flare of lupus and were on immunosuppressive drugs when they presented with prolonged fever without an obvious foci of infection, unresponsive to broad-spectrum antibiotics. They were leucopaenic upon admission, with rapid deterioration during the course of the illness. Diagnosis of penicilliosis via fungal isolation from blood culture was delayed resulting in the late initiation of antifungal agents. While both patients ultimately recovered, the delay in diagnosis led to a prolonged hospital stay with increased morbidity. Clinicians should be aware of this uncommon but emerging fungal pathogen in SLE patients and maintain a high index of suspicion in diagnosing this potentially fatal but treatable disease.

Pneumocystis jirovecii pneumonia 13 years post renal transplant following a recurrent cytomegalovirus infection.

Pneumocystis jirovecii (formerly Pneumocystis carinii) pneumonia (PCP) is a rare but serious infection that usually occurs within a year after solid organ transplantation. PCP may occur after 1 year post transplantation, but the rate is reported to be very low. Studies have shown an association between cytomegalovirus (CMV) infection in solid organ transplant patients and an increased risk of opportunistic infection. This increased risk is thought to be a result of the immunomodulatory effects of the CMV infection. We present a case of PCP infection occurring 13 years after a renal transplantation. This occurred following a recurrent CMV infection while the patient was on low-dose immunosuppressants.

Esophageal tissue engineering: an in-depth review on scaffold design.

Treatment of esophageal cancer often requires surgical procedures that involve removal. The current approaches to restore esophageal continuity however, are known to have limitations which may not result in full functional recovery. In theory, using a tissue engineered esophagus developed from the patient's own cells to replace the removed esophageal segment can be the ideal method of reconstruction. One of the key elements involved in the tissue engineering process is the scaffold which acts as a template for organization of cells and tissue development. While a number of scaffolds range from traditional non-biodegradable tubing to bioactive decellularized matrix have been proposed to engineer the esophagus in the past decade, results are still not yet favorable with many challenges relating to tissue quality need to be met improvements. The success of new esophageal tissue formation will ultimately depend on the success of the scaffold being able to meet the essential requirements specific to the esophageal tissue. Here, the design of the scaffold and its fabrication approaches are reviewed. In this paper, we review the current state of development in bioengineering the esophagus with particular emphasis on scaffold design.

Preparation and characterization of quercetin nanocrystals.

This study is to enhance the dissolution rate of a poorly water-soluble drug, quercetin, by fabricating nanocrystals using high-pressure homogenization. The particle size, crystallinity, dissolution, and antioxidant effects of fabricated quercetin nanocrystals have been investigated. Characterization of the original quercetin powder and nanocrystals was carried out by photon correlation spectroscopy (PCS), laser diffraction, scanning electron microscopy, differential scanning calorimetry (DSC), X-ray diffraction, dissolution tester, and so on. A PCS size of about 483 nm was obtained for the nanocrystals after 20 cycles of homogenization at 1500 bar. X-ray diffraction and DSC studies revealed that the lyophilized quercetin nanoparticles were crystalline after high-pressure homogenization. The percent dissolution efficiency, relative dissolution, mean dissolution time, difference factor (f(1)), and similarity factor (f(2)) were calculated for the statistical analysis. It was found that the dissolution of the drug nanocrystals was much higher than that of the pure drug at pH 6.8 and 1.2. The antioxidant activity and reducing power of the quercetin nanocrystals were more effective than the original quercetin.