High-speed k-linear swept laser using acousto-optic deflectors with Doppler shift compensation for optical coherence tomography.

Swept laser based on the acousto-optic deflector (AOD) is a promising swept source in optical coherence tomography (OCT) applications for its high wavenumber linear sweep without mechanical motion. However, the poor coherence length and the elongated cavity of the laser imposed limitations on the acquisition of high-quality images with adequate imaging depth and high imaging speed. In this Letter, we demonstrate a compact high-speed wavenumber linear swept laser based on AOD using Doppler shift compensation, achieving a high linearity of Pearson's R of 0.999991, a duty cycle of ∼100%, an extended coherence length of 5.7 mm, an output power of 18 mW, and excellent phase stability at a sweep speed of 500 kHz. OCT structural images with a system sensitivity of 103.2 dB and OCT angiography (OCTA) of human palm in vivo have been successfully performed, serving as a compelling demonstration of the excellent performance of this swept laser. We believe that the proposed laser will be of high potential in various clinical and industrial applications in the future.

Involvement of Histone Acetyltransferase 1 (HAT1) in the Spermatogenesis of Non-Condensed Nuclear Sperm in Chinese Mitten Crab, Eriocheir sinensis.

Chinese mitten crab, Eriocheir sinensis, is a decapod crustacean with a special, non-condensated nucleus in the sperm. Studies have shown that the nuclear compact state of male germ cells during the spermatogenesis is closely related to histone modification. To explore the possible role of histone acetyltransferase 1 (HAT1) in the chromatin organization during the E. sinensis spermatogenesis, we took the testis tissues of both adult and juvenile crabs as the materials of study and analyzed the biological functions of HAT1 by whole transcriptome sequencing and bioinformatics, then further analyzed the expression and distribution of HAT1 using the methods of RT-qRCR, western blotting, and immunofluorescence location. The results showed that HAT1 is an alkaline-unstable hydrophilic protein. It was predicted to interact with a variety of histones and chromosome assembly proteins, including Asf1b, Chaf1b, and Hist1h3f, and is involved in many biological functions pertaining to chromatin dynamics such as chromatin organization, DNA dependent nucleosome assembly, DNA conformational changes, and so on. HAT1 was up-regulated in the adult testes compared to the juvenile (n = 3, P < 0.05). HAT1 was mainly located in the nuclei of male germ cells of E. sinensis. As spermatogenesis proceeded, the expression of HAT1 decreased and even disappeared in the nuclei (n = 3, P < 0.05). HAT1 is an important player in histone acetylation, which facilitates chromatin alteration in a three-dimensional conformation. The expression of HAT1 in different male germ cells might indicate the chromatin dynamics at the diversity stages of spermatogenesis. The high expression of HAT1 at the early stages of E. sinensis spermatogenesis hints the active involvement in chromatin organization, while its progressively reduced expression accompanied by the progression of spermatogenesis suggests a relatively gradual stabilization and stereotyping of chromatin. As for the disappearance of HAT1 in mature sperm with non-condensed nuclei, the reduction in histones targeted by HAT1 or histone acetylation may be an important initiator.

Polarization-isolated stretched-pulse mode-locked swept laser for 10.3-MHz A-line rate optical coherence tomography.

Stretched-pulse mode-locked (SPML) lasing based on a chirped fiber Bragg grating (CFBG) has proven to be a powerful method to generate wavelength-swept lasers at speeds of tens of megahertz. However, light transmitted through the CFBG may lead to undesirable laser oscillation that disrupts the mechanism of the laser active mode locking in the theta ring cavity. In this Letter, we demonstrate a simple and low-cost approach to suppress the transmitted light and achieve an effective duty cycle of ∼100% with only one CFBG and no need for intra-cavity semiconductor optical amplifier (SOA) modulation, extra-cavity optical buffering, and post amplification. By utilizing polarization isolation of the bi-directional CFBG, a swept laser centered at 1305 nm, with repetition rate of 10.3 MHz, optical power of 84 mW, and 3 dB bandwidth of 109 nm, is demonstrated. Ultrahigh speed 3D optical coherence tomography (OCT) structural imaging of a human palm in vivo using this swept laser is also demonstrated. We believe that this ultrahigh speed swept laser will greatly promote the OCT technique for industrial and biomedical applications.

Conjunctival microbiome changes in soft contact lens users and contact lens discomfort patients.

INTRODUCTION: Contact lens discomfort (CLD) acts as a challenging problem, and the associated conjunctival microbiome changes were unclear. MATERIAL AND METHODS: Conjunctival sac swab samples were collected from 12 eyes of nonwearers (NW), 12 eyes of asymptomatic contact lens (ACL) wearers, and 11 eyes of CLD. The V3-V4 region of the 16S rRNA gene sequencing was used to investigate differences among three groups. RESULTS: No differences in alpha diversity were observed among the three groups. The beta diversity showed a distinct microbiome composition between ACL and CLD group (P = 0.018) with principal coordinate analysis. The relative abundance of Firmicutes was significantly higher in CLD (48.18%) than in ACL (13.21%) group (P = 0.018). The abundance of Bacillus in patients with ACL (0.05%) or with CLD (0.02%) were significantly lower than that in the NW (1.27%) group (P = 0.024, 0.028, respectively). Moreover, the abundance of Firmicutes was positively correlated with the OSDI scores in CLD patients (r = 0.817, P < 0. 01, Spearman). DISCUSSIONS: Patients with CLD have various degrees of bacterial microbiota imbalance in the conjunctival sac, compared with NW and ACL groups. CONCLUSION: Firmicutes may serve as a potential biomarker for the CLD patients.

In the current study, we investigated the conjunctival microbiome changes among nonwearers (NW), asymptomatic contact lens (ACL) wearers, and contact lens discomfort (CLD) patients using high-throughput 16S rRNA gene sequencing, and correlated relative abundances of the microbiota with clinical parameters.The relative abundance of Firmicutes was higher in CLD than that in ACL group. The abundance of Bacillus was lower in ACL or CLD group than that in NW group. The abundance of Firmicutes was positively correlated with the OSDI scores in CLD patients.Firmicutes may serve as a potential biomarker for the CLD patients.

Intraperitoneal Injection of MCC950 Inhibits the Progression of Myopia in Form-Deprivation Myopic Mice.

Myopia, one of the most prevalent ocular diseases worldwide, is projected to affect nearly half of the global population by 2050. The main cause of myopia in most patients is axial myopia, which primarily occurs due to the elongation of the eyeball, driven by changes in the extracellular matrix (ECM) of scleral cells. Previous studies have shown that NLRP3, an important inflammatory mediator, plays a critical role in regulating the expression of MMP-2 in the sclera. This, in turn, leads to a decrease in the expression of Collagen-1, a major component of the scleral ECM, triggering the remodeling of the scleral ECM. This study aimed to investigate the effect of MCC950, an inhibitor of NLRP3, on the progression of myopia using a mouse form-deprivation myopia (FDM) model. The FDM mouse model was constructed by subjecting three-week-old C57BL/6J mice to form-deprivation. The mice were divided into experimental (n = 10/group; FDM2M, FDM4M, FDM2W, and FDM4W) and control groups (n = 5/group). The experimental groups were further categorized based on the duration of form deprivation (2 and 4 weeks, labeled as 2 and 4, respectively) and the type of injection received (MCC950 or saline, labeled as M and W, respectively). MCC950 was injected at a concentration of 50 mg/mL, with a dose of 10 mg per kilogram of body weight. Meanwhile, the saline group received the same volume of saline. Refraction and axial length measurements were performed for each eye. The expression levels of NLRP3, caspase-1, IL-1ß, IL-18, MMP-2, and Collagen-1 in the sclera were assessed using immunohistochemistry and Western blotting. The intraperitoneal injection of MCC950 did not significantly affect refraction or axial length in normal mice (p > 0.05). However, in FDM mice, MCC950 attenuated the elongation of the axial length and resulted in a smaller shift towards myopia compared to the saline group (FDM4M vs. FDM4W, p = 0.03 and p < 0.05, respectively). MCC950 decreased MMP-2 expression (p < 0.05) but increased Collagen-1 expression (p < 0.05) in the experimental eyes when compared to the saline group. Within the MCC950 group, the expression of MMP-2 was increased in the experimental eyes at 4 weeks (p < 0.05), while that of Collagen-1 was decreased (p < 0.05), which is consistent with changes in refractive error. Immunohistochemical analysis yielded similar results (p < 0.05). MCC950 also reduced the expression levels of NLRP3 (p = 0.03), caspase-1 (p < 0.05), IL-1ß (p < 0.05), and IL-18 (p < 0.05) in the experimental eyes compared to the saline group. Within the MCC950 group, the expression levels of NLRP3 and caspase-1 were comparable between the experimental and control eyes (p > 0.05), whereas IL-18 expression was higher in experimental eyes (p < 0.05). IL-1ß expression was higher in the experimental eyes only at week 4 (p < 0.05). The intraperitoneal injection of MCC950 can inhibit the progression of myopia in FDM mice, possibly by regulating collagen remodeling in the sclera through the NLRP3-MMP-2 signaling pathway. Therefore, MCC950 holds promise as a potential therapeutic agent for controlling the progression of myopia.

[Analysis of TUBB4A gene variant in a patient with adolescent-onset hypomyelinating leukodystrophy with atrophy of basal ganglia and cerebellum].

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a patient with adolescent-onset hypomyelinated leukodystrophy with atrophy of basal ganglia and cerebellum (H-ABC). METHODS: A patient who was diagnosed with H-ABC in March 2018 at the First Affiliated Hospital of Nanjing Medical University was selected as the study subject. Clinical data was collected. Peripheral venous blood samples of the patient and his parents were collected. The patient was subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing. RESULTS: The patient, a 31-year-old male, had manifested with developmental retardation, cognitive decline and abnormal gait. WES revealed that he has harbored a heterozygous c.286G>A variant of the TUBB4A gene. Sanger sequencing confirmed that neither of his parents has carried the same variant. Analysis with SIFT online software indicated the amino acid encoded by this variant is highly conserved among various species. This variant has been recorded by the Human Gene Mutation Database (HGMD) with a low population frequency. The 3D structure constructed by PyMOL software showed that the variant has a harmful effect on the structure and function of the protein. According to the guidelines formulated by the American College of Medical Genetics and Genomics (ACMG), the variant was rated as likely pathogenic. CONCLUSION: The c.286G>A (p.Gly96Arg) variant of the TUBB4A gene probably underlay the hypomyelinating leukodystrophy with atrophy of basal ganglia and cerebellum in this patient. Above finding has enriched the spectrum of TUBB4A gene variants and enabled early definitive diagnosis of this disorder.

Effect of NLRP3 repression on NLRP3 inflammasome activation in human corneal epithelial cells with black carbon exposure.

PURPOSE: To investigate the inhibitory effects of NLRP3 siRNA on NLRP3 inflammasome activation in human corneal epithelial cells (HCECs) with fresh black carbon (FBC) particles and ozone-oxidized BC (OBC) particles treatment. METHODS: HCECs were transfected with NLRP3 siRNA or control siRNA for 48 h, followed by 200 µg/ml FBC or OBC suspension for an additional 72 h. Untreated controls were cells with no siRNA transfection or BC treatment. RT-qPCR and Western blot were used to measure mRNA and protein levels of components of the NLRP3 inflammasome (NLRP3, ASC, and Caspase-1) and downstream cytokine (IL-1ß), respectively. RESULTS: Compared with untreated control cells, mRNA levels of NLRP3, ASC, Caspase-1, and IL-1ß were significantly higher (p < 0.05) in control siRNA transfected cells with BC treatments. Compared with the control siRNA transfected cells, NLRP3 siRNA transfection reduced the expression of NLRP3 and ASC, whereas it had a limited effect on the expression of Caspase-1 and IL-1ß with FBC or OBC exposures. Under FBC treatment, the reductions of NLRP3 and Caspase-1 mRNA levels were 53.5% (p < 0.001) and 34.2% (p < 0. 01), respectively, and NLRP3 and ASC protein levels were lowered by 58.2% (p < 0.001) and 45.4% (p < 0.001), respectively. Under OBC treatment, the reductions of NLRP3 and Caspase-1 mRNA levels were 39.8% (p < 0.001) and 25.6% (p < 0.05), respectively, and NLRP3 and ASC protein levels were lowered by 44.8% (p < 0.001) and 41.7% (p < 0.001), respectively. Moreover, mRNA levels of ASC and IL-1ß, the protein levels of Caspase-1 and IL-1ß showed a tendency to decrease in NLRP3 siRNA transfected cells, it was statistically insignificant (p > 0.05). CONCLUSIONS: NLRP3 siRNA transfection could partially reverse the increased mRNA levels of NLRP3 and Caspase-1, the protein levels of NLRP3 and ASC in HCECs with BC treatment, whereas the reductions of protein levels of Caspase-1 and IL-1ß were not significant, indicating that NLRP3 siRNA has a limited inhibitory effect on the activation of NLRP3 inflammasome triggered by BC.

Theoretical and experimental study of hybrid optical computing engine for arbitrary-order FRFT.

Fractional Fourier transform (FRFT) is the generalization of Fourier transform. It provides many significant advantages, such as fractional order as the new degree of freedom and high efficiency and great performance for non-stationary signal analysis/processing, that other operations including Fourier transform cannot. Here, we report a hybrid optical system for computation of arbitrary-order FRFT of temporal signals. In experiment, the fractional-domain information of input temporal signals could be directly acquired by detector. In addition, the optical computing results are in good agreement with numerical results. Then we apply the optical computing engine to demodulation of chirp spread spectrum signals. Using sub-Nyquist sampling, the proposed technology could greatly save the number of measurements in demodulation. The compression ratio could be as low as 0.4%, because of the high compression performance of chirp signals in FRFT domain. As a result, the proposed technology has unique advantages in analysis and information extraction for non-stationary signals, especially for chirp-like signals, and may become a powerful optical time-frequency analysis tool for temporal signals.

High-speed all-optical processing for spectrum.

Data-processing techniques in spectroscopy are fundamental and powerful analytical tools for lots of practical applications. In the age of big data, high-speed data-processing in spectroscopy is in urgent need, especially for the real-time analysis/feedback of data stream of spectroscopy or the capture of non-repetitive/rare phenomena in fast dynamic process. So far, intensive researches focus on high-speed processing of light signal in time/spatial domain but few people find a way to do it in spectral domain. Here, we report an optical computing technology for high-speed optical spectrum processing with features of real time, multiple functions, all-fiber configuration and immunity to electromagnetic interference. The software-controlled system could perform as, but not limited to, the first-order (or arbitrary fractional-order) differentiator/integrator/Hilbert transformer and tunable band-pass filter, respectively, to handle spectral data rapidly. High-speed processing of optical spectrum at a rate of 10,000,000 times per second is demonstrated.

Prevalence and correlates of Mycoplasma genitalium infection among patients attending a sexually transmitted infection clinic in Guangdong, China: a cross-sectional study.

BACKGROUND: Mycoplasma genitalium (MG) causes urogenital tract infections and is associated with reproductive morbidity. Although MG has been reported across many regions and population groups, it is not yet routinely tested for in China. Our study contributes to current research by reporting the prevalence and correlates of MG infection in patients attending a sexually transmitted infection (STI) clinic in Guangdong from Jan 2017-May 2018. METHODS: Urethral (from 489 men) and endo-cervical (from 189 women) samples, blood samples, and patient histories (via questionnaires) were collected. Doctors clinically diagnosed anogenital warts (GW) during the examination (n = 678). The presence of MG was evaluated using an in-house via polymerase chain reaction protocol. We also tested all participants for herpes simplex virus-2 (HSV-2), Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), syphilis and HIV. Univariate and multivariate logistic regression were used to evaluate factors associated with MG. RESULTS: MG was detected in 7.2% (49/678) of the patients (men, 7.4%; women, 6.9%). The MG positivity rate was 14.2% among symptomatic patients, and 5.6% for asymptomatic patients, respectively. Only 36.7% (18/49) Mg positive patients were symptomatic. Among the MG-infected patients, 10.2% were co-infected with CT, 6.1% with NG, 8.2% with HSV-2, 4.1% with syphilis and 22.4% with GW. Presentation with clinical symptoms was significantly associated with MG infection [OR = 2.52 (2.03-3.13)]. In our analysis, MG was not associated with other STIs. CONCLUSIONS: MG is a relatively common infection among individuals attending an STI clinic in Guangdong Province. Routine testing of symptomatic patients may be necessary, and more epidemiological studies are needed to provide evidence for future testing guidelines.

Speckle reducing OCT using optical chopper.

Optical coherence tomography (OCT) has been an important and powerful tool for biological research and clinical applications. However, speckle noise significantly degrades the image quality of OCT and has a negative impact on the clinical diagnosis accuracy. In this paper, we propose a novel speckle noise suppression technique which changes the spatial distribution of sample beam using a special optical chopper. Then a series of OCT images with uncorrelated speckle patterns could be captured and compounded to improve the image quality without degradation of resolution. Typical signal-to-noise ratio improvement of ∼6.4 dB is experimentally achieved in tissue phantom imaging with average number n = 100. Furthermore, compared with conventional OCT, the proposed technique is demonstrated to view finer and clearer biological structures in human skin in vivo, such as sweat glands and blood vessels. The advantages of low cost, simple structure and compact integration will benefit the future design of handheld or endoscopic probe for biomedical imaging in research and clinical applications.

Macrolide and fluoroquinolone associated mutations in Mycoplasma genitalium in a retrospective study of male and female patients seeking care at a STI Clinic in Guangzhou, China, 2016-2018.

BACKGROUND: Antimicrobial resistance in M. genitalium is a growing clinical problem. We investigated the mutations associated with macrolide and fluoroquinolone resistance, two commonly used medical regimens for treatment in China. Our aim is to analyze the prevalence and diversity of mutations among M. genitalium-positive clinical specimens in Guangzhou, south China. METHODS: A total of 154 stored M. genitalium positive specimens from men and women attending a STI clinic were tested for macrolide and fluoroquinolone mutations. M. genitalium was detected via TaqMan MGB real-time PCR. Mutations associated with macrolide resistance were detected using primers targeting region V of the 23S rRNA gene. Fluoroquinolone resistant mutations were screened via primers targeting topoisomerase IV (parC) and DNA gyrase (gyrA). RESULTS: 98.7% (152/154), 95.5% (147/154) and 90.3% (139/154) of M. genitalium positive samples produced sufficient amplicon for detecting resistance mutations in 23S rRNA, gyrA and parC genes, respectively. 66.4% (101/152), 0.7% (1/147) and 77.7% (108/139) samples manifested mutations in 23S rRNA, gyrA and parC genes, respectively. A2072G (59/101, 58.4%) and S83I (79/108, 73.1%) were highly predominating in 23S rRNA and parC genes, respectively. Two samples had amino acid substitutions in gyrA (M95I and A96T, respectively). Two samples had two amino acid substitutions in parC (S83I + D87Y). 48.6% (67/138) of samples harbored both macrolide and fluoroquinolone resistance-associated mutations. The most common combination of mutations was A2072G (23S rRNA) and S83I (parC) (40/67, 59.7%). One sample had three amino acid changes in 23S rRNA, gyrA and parC genes (A2072G + A96T + S83I). CONCLUSIONS: The high antimicrobial resistance rate of M. genitalium in Guangzhou is a very worrying problem and suggests that antimicrobial resistance testing and the development of new antibiotic regimens are crucially needed.

Compressed sensing spectral domain optical coherence tomography with a hardware sparse-sampled camera.

We present a sparse-sampled camera for compressed sensing spectral domain optical coherence tomography (CS SD-OCT), which is mainly composed of a novel mask with specially designed coating and a commercially available CCD camera. The sparse-sampled camera under-samples the SD-OCT spectrum in hardware, thus reduces the acquired image data and can achieve faster A-scan speed than conventional CCD camera with the same pixel number. Compared with a conventional SD-OCT system, the CS SD-OCT system equipped with the sparse-sampled camera has better fall-off and SNR performance. CS-OCT imaging of bio-tissue is also demonstrated.

MicroRNA-147b Promotes Proliferation and Invasion of Human Colorectal Cancer by Targeting RAS Oncogene Family (RAP2B).

BACKGROUND: MicroRNAs (miRNAs), a class of small-regulatory RNA molecules, were closely involved in the pathogenesis of a broad-spectrum of colorectal cancer (CRC). But role of miR-147b in CRC still remains unclear. METHODS: Real-time RT-PCR or Western blotting was utilized to detect the expressions of miR-147b and RAP2B in CRC cell lines and tissues. Luciferase reporter assays were conducted to detect the associations between miR-147b and 3'UTRs of RAP2B. A series of assays were performed to evaluate the effect of miR-147b on proliferation, migration, and invasion of CRC in vitro and in vivo. RESULTS: We found that the level of miR-147b was significantly lower in CRC tissues than in normal tissues (p = 0.0006). Enforced expression of miR-147b led to suppression of CRC cell proliferation in vitro and tumor growth in vivo. Specifically, miR-147b promoted proliferation by arresting CRC cells in the G1/G0 phase. Mechanically, RAP2B was identified as a direct target gene of miR-147b and RAP2B rescued the suppression of proliferation and invasion reduced by miR-147b in CRC cells. CONCLUSIONS: miR-147b not only plays important roles in the regulation of cell proliferation and tumor growth in CRC, which might be a potential prognostic marker or therapeutic target for CRC.

Relationship between serum quantitative HBsAg and HBV DNA levels in chronic hepatitis B patients.

Serum hepatitis B surface antigen (HBsAg) level has been developed as an important marker to predict treatment outcome recent years. The authors aimed to identify the correlation between quantitative HBsAg and hepatitis B virus (HBV) DNA level in chronic hepatitis B (CHB) patients and explore whether quantitative HBsAg can be used as a surrogate marker of serum HBV DNA for CHB patients. One hundred seventy-three patients were included in this study. Patients were divided into two groups: Hepatitis B e antigen (HBeAg) positive and negative patients. There was a positive correlation between quantitative HBsAg and HBV DNA level in HBeAg positive patients (r = 0.509, P < 0.001) and poor correlation in HBeAg negative patients (r = 0.176, P = 0.096). Interestingly, completely no correlation (r = -0.01, P = 0.994) was found in younger HBeAg negative patients (<40 years old), whereas in older HBeAg negative patients (>40 years old) there is a positive correlation (r = 0.448, P = 0.003). Mean HBsAg titer and Alanine aminotransferase (ALT) level were significantly higher in HBeAg positive group (3.81 log10 IU/mL; 105 IU/mL) than in negative group (2.85 log10  IU/mL; 32 IU/mL) (P <  0.001). We concluded that quantitative HBsAg could reflect HBV DNA level in HBeAg positive patients, but could not surrogate for HBV DNA level in HBeAg negative patients. Our study improves understanding of the relationship between HBsAg titers and HBV DNA levels in CHB patient and may have implications for future treatment algorithms evaluating the HBsAg titers in both HBeAg positive and negative patients.

Gonorrhea and chlamydia prevalence in different anatomical sites among men who have sex with men: a cross-sectional study in Guangzhou, China.

BACKGROUND: A high rectal and oropharyngeal sexually transmitted infection (STI) burden has been reported among men who have sex with men (MSM) in many regions, but little data exists on rectal and oropharyngeal STIs among MSM in China. The purpose of this study was to determine the prevalence of gonorrhea and chlamydia at different anatomic sites among MSM in Guangzhou, China. METHODS: We recruited a cross-sectional sample of MSM in one Chinese city and collected detailed information about socio-demographic characteristics and sexual behaviors. Men had urine, rectal, and pharyngeal swab samples tested for gonorrhea and chlamydia using nucleic acid amplification tests (NAAT). Univariate and multivariate logistic regressions were used to evaluate factors associated with gonorrhea and chlamydia. Among men without any STI symptoms, we also examined the prevalence of gonorrhea and chlamydia by anatomical site. RESULTS: We enrolled 463 men between January 2015 and March 2017. A total of 58/463 (12.5%) of men had gonorrhea and 84/463 (18.1%) had chlamydia. MSM with gonorrhea were more likely to have been recruited from the STI clinic (OR 3.41, 95% CI 1.94-5.99), living with HIV (OR 2.41, 95% CI 1.18-4.92), diagnosed had STI co-infection (OR 2.55, 95% CI 1.39-4.69). MSM with chlamydia were more likely to be students (OR 1.8, 95% CI 0.99-3.39). Most gonorrhea (34/58, 59%) and chlamydia (64/84, 76%) infections were not associated with STI symptoms. CONCLUSION: Asymptomatic gonorrhea and chlamydia infection were common in this sample of Chinese MSM. Further research is necessary to determine optimal STI screening programs.

Effects of mesalazine enemas on lymphoid follicular proctitis.

Lymphoid follicular proctitis (LFP) is an uncommon inflammatory disease that is characterized by rectal bleeding, congested and granular mucosa without ulceration and abnormal and coalescing hyperplastic lymphoid follicles without acute inflammatory changes. The lesions are usually confined to the rectal mucosa. LFP therapy is not well defined. Herein, we present a case of LFP that was resolved with a rapid administration of mesalazine enemas. A 35-year-old male was admitted to our hospital due to intermittent rectal bleeding associated with stools. Total colonoscopy revealed nodular mucosa with top pinpoint-like ulcers from the rectum to the border between the sigmoid flexure and the rectum. The nodules congested together on the lower rectal segment and occupied 2/3 of the rectal lumina. Endoscopic submucosal dissection was performed in order to obtain more specimens for histologic examination, which revealed marked lymphoid follicular hyperplasia with prominent germinal centers and a conserved mantle zone. Treatment was started with mesalazine enemas of 4 g q.d. and the patient was asymptomatic after three days. All the lesions disappeared two months later. Mesalazine enemas could be a promising and effective therapeutic option for LFP therapy.

Self-Assembly of Extended Head-to-Tail Triangular Pt3 Macrocycles into Nanotubes.

New pyridylsalicylaldimine-based ligands with extended conjugation have been synthesized. The reaction of these ligands with K2PtCl4 yielded triangular Pt3 macrocycles rather than the anticipated Pt4 macrocycles. The macrocycles have been analyzed in solution by variable-temperature and variable-concentration 1H NMR, NOESY, and DOSY spectroscopy studies. These investigations show that the macrocycles aggregate at room temperature in solution by an entropy-driven process. In the solid state, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and transmission electron microscopy studies show that the macrocycles aggregate into nanotubular structures. Triangular platinum-containing macrocycles with the expanded pyridylsalicylaldimine ligands are promising for constructing nanotubes and discotic liquid crystals.

Treatment of Ischemia-Reperfusion Injury of the Skin Flap Using Human Umbilical Cord Mesenchymal Stem Cells (hUC-MSCs) Transfected with "F-5" Gene.

BACKGROUND Recent studies have shown that skin flap transplantation technique plays an important role in surgical procedures. However, there are many problems in the process of skin flap transplantation surgeries, especially ischemia-reperfusion injury, which directly affects the survival rate of the skin flap and patient prognosis after surgeries. MATERIAL AND METHODS In this study, we used a new method of the "stem cells-gene" combination therapy. The "F-5" gene fragment of heat shock protein 90-α (Hsp90-α) was transfected into human umbilical cord mesenchymal stem cells (hUC-MSCs) by genetic engineering technique. RESULTS The synergistic effects of "F-5" gene and hUC-MSCs in the treatment of ischemia-reperfusion injury of the skin flap were confirmed by histochemical and immunohistochemical methods. CONCLUSIONS This study showed that the hUC-MSCs transfected with "F-5" gene can effectively improve the repair of ischemia-reperfusion injury.

The Rich Tautomeric Behavior of Campestarenes.

Campestarenes are a new family of Schiff-base macrocycles that form selectively in a one-step synthesis. These macrocycles with five-fold symmetry show solvent-dependent tautomerization and dimerization or aggregation. In this paper, we have prepared new soluble campestarenes that do not aggregate. The initial single-crystal X-ray diffraction study of a campestarene reveals that these macrocycles are nearly flat. The tautomeric behavior of the campestarenes has been extensively studied by variable-temperature, multinuclear NMR spectroscopy, UV/Vis spectroscopy, and IR spectroscopy. In polar solvents, such as DMF, the molecules exist predominantly in their keto-enamine form, but the enol-imine tautomer is dominant in non-polar solvents. A detailed computational study of the tautomeric forms of campestarenes provides a theoretical basis for their behavior and corroborates the experimental data. The results of this study give the first comprehensive understanding of the electronic and spectroscopic properties of these pentagonal macrocycles.