Chidamide in combination with azacitidine for an elderly patient with peripheral T cell lymphoma­not otherwise specified: A case report.

Peripheral T cell lymphoma (PTCL) is a type of aggressive non-Hodgkin's lymphoma with poor prognosis. PTCL-not otherwise specified (PTCL-NOS) is one of its most common pathological types. PTCL is not sensitive to conventional chemotherapy regimens and treatment is particularly limited in elderly patients due to their poor tolerance to chemotherapy. The present report shares the treatment experience of one elderly PTCL-NOS case, which achieved complete remission by reduced-intensity chemotherapy with chidamide in combination with azacitidine following the onset of organ failure and chemotherapy insensitivity. The 9-month follow-up showed sustained remission and the long-term efficacy of this regimen is also promising.

Effect of endoscopic therapy and drug therapy on prognosis and rebleeding in patients with esophagogastric variceal bleeding.

Esophagogastric variceal bleeding (EVB) is one of the common digestive system emergencies with poor prognosis and high rate of rebleeding after treatment. To explore the effects of endoscopic therapy and drug therapy on the prognosis and rebleeding of patients with EVB, and then select better treatment methods to effectively improve the prognosis. From January 2013 to December 2022, 965 patients with EVB who were hospitalized in gastroenterology Department of the 940 Hospital of Joint Logistic Support Forces of PLA were retrospectively analyzed. Patients were divided into endoscopic treatment group (ET, n = 586) and drug treatment group (DT, n = 379). Propensity score matching (PSM) analysis was performed in both groups, and the general information, efficacy and length of hospital stay were recorded. The patients were followed up for 3 months after bleeding control to determine whether rebleeding occurred. There were 286 cases in each group after PSM. Compared with DT group, ET had higher treatment success rate (P < 0.001), lower rebleeding rate (P < 0.001), lower mortality rate within 3 months, and no significant difference in total hospital stay (P > 0.05). Compared with drug therapy, endoscopic treatment of EVB has short-term efficacy advantages, and can effectively reduce the incidence of rebleeding and mortality within 3 months.

Demethylase FTO inhibits the occurrence and development of triple-negative breast cancer by blocking m 6A-dependent miR-17-5p maturation-induced ZBTB4 depletion.

Triple-negative breast cancer (TNBC) is a subtype of breast cancer, and its mechanisms of occurrence and development remain unclear. In this study, we aim to investigate the role and molecular mechanisms of the demethylase FTO (fat mass and obesity-associated protein) in TNBC. Through analysis of public databases, we identify that FTO may regulate the maturation of miR-17-5p and subsequently influence the expression of zinc finger and BTB domain-containing protein 4 (ZBTB4), thereby affecting the occurrence and progression of TNBC. We screen for relevant miRNAs and mRNAs from the GEO and TCGA databases and find that the FTO gene may play a crucial role in TNBC. In vitro cell experiments demonstrate that overexpression of FTO can suppress the proliferation, migration, and invasion ability of TNBC cells and can regulate the maturation of miR-17-5p through an m 6A-dependent mechanism. Furthermore, we establish a xenograft nude mouse model and collect clinical samples to further confirm the role and impact of the FTO/miR-17-5p/ZBTB4 regulatory axis in TNBC. Our findings unveil the potential role of FTO and its underlying molecular mechanisms in TNBC, providing new perspectives and strategies for the research and treatment of TNBC.

The Neuroprotective Effect of Activation of Sigma-1 Receptor on Neural Injury by Optic Nerve Crush.

Purpose: This study aimed to explore the neuroprotective effects of sigma-1 receptor (S1R) on optic nerve crush (ONC) mice by upregulating its expression through intravitreal injection of adeno-associated virus (AAV). Methods: The animals were divided into four groups. Mice that underwent ONC were administered an intravitreal injection with blank vector (ONC group), with AAV targeting downregulation of S1R (S1R-sh group), or with AAV targeting overexpression of S1R (S1R-AAV group). Mice in the control group underwent intravitreal injection with blank vector. The thickness of each layer of the retina was measured through optical coherence tomography, and the apoptotic rate of retinal neurons was determined using the TUNEL assay. The expression levels of brain-derived neurotrophic factor (BDNF) and S1R were quantified through western blot. Electroretinogram (ERG) was performed to evaluate the visual function. Results: The thickness of the total retina (P = 0.001), ganglion cell layer (P = 0.017), and inner nuclear layer (P = 0.002) in S1R-AAV group was significantly thicker than that of the ONC group. The number of retinal apoptotic cells in the S1R-AAV group was 23% lower than that in the ONC group (P = 0.002). ERG results showed that, compared to the ONC group, the amplitudes of the a- and b-waves were higher in the S1R-AAV group (a-wave, P < 0.001; b-wave, P = 0.007). Western blot showed that the expression of BDNF in the S1R-AAV group was higher than that in the ONC group (P < 0.001). Conclusions: Activation of S1R in the retina through intravitreal injection of AAV can effectively maintain the retina structure, promote neuronal cell survival, and protect visual function.

Risk factors of infection among close contacts of COVID-19: A systematic review and meta-analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) was first detected in December 2019, and declared as a pandemic by the World Health Organization (WHO) on March 11, 2020. The current management of COVID-19 is based generally on supportive therapy and treatment to prevent respiratory failure. METHODS: PubMed, Web of Science, Embase, CNKI, and other databases were searched by computer, and relevant literature published from December 2019 to November 2022 on the influencing factors of infection in close contacts with novel coronavirus pneumonia was collected. Meta-analysis was carried out after literature screening, quality assessment, and data extraction. RESULTS: A total of 425 articles were retrieved and 11 were included. Meta-analysis showed that there were 6 risk factors, and the combined OR value and 95% CI of each influencing factor were 5.23 (3.20, 8.57) for family members, 1.63 (0.56, 4.77) for regular contact, 2.14 (0.62, 7.32) for the elderly, 0.58 (0.001569.89) for cohabitation, 1.97 (1.02, 3.82) for women and 0.75 (0.01, 54.07) for others. The Deeks' funnel diagram indicates that there is no potential publication bias among the included studies. CONCLUSION: Family members and gender differences are the risk factors of infection among close contacts, and it cannot be proved that there are differences in infection among frequent contact, advanced age, and living together.

Regulation of Retinal Melanopsin on Lens-induced Myopia in Guinea Pigs.

SIGNIFICANCE: Investigation of the mechanism and the role of melanopsin in lens-induced myopia is necessary to find out potential targets in the prevention of myopia development. PURPOSE: We aimed to study the effect and mechanism of retinal melanopsin on lens-induced myopia in guinea pigs, as well as the interactions between melanopsin and other myopic regulation neurotransmitters such as dopamine and melatonin, and to explore the possible role of melanopsin in the prevention of myopia development. METHODS: Twenty-day-old tricolor guinea pigs were randomly divided into four groups: control group, defocus group, defocus + AA92593 group, and defocus + dimethyl sulfoxide (DMSO) group. The defocus eyes wore -6.00 D lens. In the defocus + AA92593 group, the vitreous cavities were injected with melanopsin antagonist AA92593. In the defocus + DMSO group, the vitreous cavities were injected with 5% DMSO as the administration control. The expression of retinal melanopsin protein was measured with immunofluorescence staining and Western blot. The content of dopamine and melatonin in the retina was determined by the high-performance liquid chromatography electrochemical method. RESULTS: Compared with the defocus group, intravitreal injection of AA92593 resulted in increased axial length of the defocus eyes (defocus, 8.05 ± 0.09 mm; defocus + AA92593, 8.15 ± 0.11 mm; P = .008), lower refractive degree (defocus, -1.98 ± 0.82 D; defocus + AA92593, -2.59 ± 0.97 D; P = .05), decreased relative expression of retinal melanopsin protein (defocus, 0.67 ± 0.11; defocus + AA92593, 0.20 ± 0.06; P < .0001), and increased melatonin content in the defocus eyes (defocus, 0.38 ± 0.09 ng/mg; defocus + AA92593, 0.55 ± 0.13 ng/mg; P = .01), but it had no obvious effect on dopamine content (defocus, 0.64 ± 0.18 ng/mg; defocus + AA9259, 0.61 ± 0.17 ng/mg; P > .99). The melatonin content of retina in the defocus + AA92593 group was correlated with refractive error (Pearson correlation coefficient = -0.68, P = .006) and eye axis length (Pearson correlation coefficient = 0.74, P = .02). CONCLUSIONS: Retinal melanopsin has inhibitory effect on lens-induced myopia development in guinea pigs, and such effect may be related to retinal melatonin.

Different roles of retinal dopamine in albino Guinea pig myopia.

PURPOSE: To investigate whether the different role of ocular dopamine was involved in the myopic development between spontaneous myopia (SM) and form deprivation myopia (FDM) in albino guinea pigs. METHODS: 55 myopic animals were randomly divided into SM, Levodapa (L-DOPA), L-DOPA+carbidopa and vehicle. 70 non-myopic animals were randomly divided into normal control, FDM, L-DOPA+FDM, L-DOPA+carbidopa+FDM and vehicle. Once per day, for 14days, L-DOPA (10mg/kg) was injected intraperitoneally, and carbidopa (1µg) was injected at the same time into the peribulbar space of the right eye. Refractive parameters and dopamine content in neural retina and RPE/choroid complex were measured. RESULTS: In SM animals, high myopia was formed at 5 week of ages. L-DOPA treatment could reduce its myopic degree, and inhibit the increase of axial length and vitreous chamber depth with the increase of retinal dopamine in both eyes. Administration of carbidopa could prevent the increase of retinal dopamine induced by L-DOPA, but no influenced on its refractive state in the injected eyes. In non-SM animals, intraperitoneal L-DOPA could inhibit FDM, accompanied by the increase of retinal dopamine. Carbidopa treatment diminished the inhibition of FDM and prevented the increase in retinal dopamine by L-Dopa. Retinal dopamine was highly correlated with ocular refraction in FDM, but not in SM. There was no significant difference in dopamine content of RPE/choroid complex among all groups. CONCLUSIONS: The role of retinal dopamine was different between SM and FDM in albino guinea pigs. Although systemic L-DOPA could inhibit the development of SM and FDM, retinal dopamine was only involved in the L-DOPA inhibition on FDM, but not on SM.

Topological Organization of Metabolic Brain Networks in Pre-Chemotherapy Cancer with Depression: A Resting-State PET Study.

This study aimed to investigate the metabolic brain network and its relationship with depression symptoms using 18F-fluorodeoxyglucose positron emission tomography data in 78 pre-chemotherapy cancer patients with depression and 80 matched healthy subjects. Functional and structural imbalance or disruption of brain networks frequently occur following chemotherapy in cancer patients. However, few studies have focused on the topological organization of the metabolic brain network in cancer with depression, especially those without chemotherapy. The nodal and global parameters of the metabolic brain network were computed for cancer patients and healthy subjects. Significant decreases in metabolism were found in the frontal and temporal gyri in cancer patients compared with healthy subjects. Negative correlations between depression and metabolism were found predominantly in the inferior frontal and cuneus regions, whereas positive correlations were observed in several regions, primarily including the insula, hippocampus, amygdala, and middle temporal gyri. Furthermore, a higher clustering efficiency, longer path length, and fewer hubs were found in cancer patients compared with healthy subjects. The topological organization of the whole-brain metabolic networks may be disrupted in cancer. Finally, the present findings may provide a new avenue for exploring the neurobiological mechanism, which plays a key role in lessening the depression effects in pre-chemotherapy cancer patients.

Analyses on the misdiagnoses of 25 patients with unilateral optic nerve sheath meningioma.

AIM: To investigate clinical features of optic nerve sheath meningioma (ONSM) that was misdiagnosed, and to find methods to reduce the misdiagnoses. METHODS: Retrospective series study. Twenty-five misdisgnosed patients with unilateral ONSM were collected from Jan. 2008 to Jan. 2015 and the clinical records reviewed. RESULTS: Patients were misdiagnosed with acute papillitis most frequently (n=17), immediately followed by optic atrophy (n=8), ischemic optic neuropathy (n=5), acute retrobulbar optic neuritis (n=5), optic disc vasculitis (n=3). For each patient, the minimum frequency of misdiagnoses was once and the maximum was 4 times. As for the lasting time of being misdiagnosed, the shortest was 1.5mo and the longest was 45mo. Twenty-one cases (84%) were once treated with glucocorticoids, and its side effects was found in seventeen patients. Twenty patients (80%) complained with varying degree of vision loss. When a definite diagnosis was made, sixteen cases (64%) showed slight exophthalmos and eighteen cases (72%) had the tubular ONSM. CONCLUSION: ONSM without loss obvious exophthalmos is easily misdiagnosed in clinic, and for most of these ONSMs are tubular.

Citicoline retards myopia progression following form deprivation in guinea pigs.

The retinal dopaminergic system is involved in the myopic shift following form deprivation. Citicoline has been demonstrated to stimulate the dopaminergic system in the brain and retina. Furthermore, citicoline has been used in many neurogenic diseases, such as senile cognitive impairment, stroke and Parkinson's disease as well as in amblyopia and glaucoma. Our aim was to investigate the effect of citicoline on the refractive state and retinal dopamine level in form deprivation myopia of guinea pigs. Guinea pigs, at an age of four weeks, were randomly divided into normal control, deprivation, deprived + citicoline and deprived + vehicle groups. Form deprivation myopia was induced by a translucent eye shield covering the right eye. Citicoline was injected intraperitoneally twice a day (500 mg/kg, 9 am and 9 pm) for 10 days. In vitro, retinal explants were cultured with citicoline for 24 h, with a final citicoline concentration of 100 µmol/L. The ocular refractive parameters and retinal dopamine content were measured. After occlusion for 10 days, the form-deprived eyes became myopic with an increase in axial length and a decrease in retinal dopamine content. The intraperitoneal injection of citicoline reduced the myopic degree (from -3.25 ± 0.77D to -0.62 ± 0.47D, P < 0.001) and partially raised retinal dopamine levels (from 0.55 ± 0.21 ng to 0.81 ± 0.24 ng, P < 0.01) in the form-deprived eyes. After 24 h of culturing retinal explants with citicoline, retinal dopamine content increased significantly (from 0.42 ± 0.14 ng to 0.62 ± 0.21 ng, P < 0.05). These results demonstrated that an intraperitoneal injection of citicoline could retard the myopic shift induced by form deprivation in guinea pigs, which was mediated by an increase in the retinal dopamine levels.

[A randomized controlled trial: acclimatization training on the prevention of motion sickness in hot-humid environment].

OBJECTIVE: Incidence and severity of motion sickness (MS) in hot-humid environment are extremely high. We tried to know the effect of two-stage training for reducing incidence and severity of ms. METHODS: Sixty male subjects were divided into experimental group and control group randomly. Subjects in experimental group received: (2) adaptation training including sitting, walking and running in hot lab. After adaptation confirmation based on subjective feeling, rectal temperature, heart rate, blood Pressure, sweat rates and sweat salt concentration, we tested both groups by Coriolis acceleration revolving chair test and recorded Graybiel's score and grading of severity to evaluate whether adaptation training was useful; (2) Anti-dizzy training 3m later of deacclimatization contained revolving chair training for 10 times. Then we did the same test as mentioned above to evaluate effect of anti-dizzy training. RESULST: Graybiel' s score and grading of severity had no difference between two groups through acclimatization training (P > 0.05). While they had difference through anti-dizzy training (P < 0.01). CONCLUSION: Adaptation training seems useless for reducing incidence and severity of MS in hot-humid environment, but anti-dizzy training is useful.

Regulation of RPE barrier function by all-trans retinoic acid in myopia.

To investigate the effect of all-trans retinoic acid (atRA) on the barrier function of myopia retinal pigment epithelium (RPE), primary RPE cells from guinea pigs were cultured on the filters as monolayer and treated with 10⁻9 M atRA. Epithelial permeability was measured by transepithelial electrical resistance (TER) and HRP concentration, western blot was used to observe the expression of intercellular junction-associated proteins. Treatment of primary cultures of confluent myopia RPE cells with atRA resulted in a progressive increase in TER and a progressive decrease of HRP concentration in the basolateral compartment. The expression of E-cadherin, Occludin and Claudin-1 proteins were up-regulated after treatment with atRA for 6h to 48 h. We concluded that atRA could promote the epithelial barrier function of myopia RPE monolayer possibly by regulating expression of intercellular junction-associated proteins.

Effect of retinoic acid on the tight junctions of the retinal pigment epithelium-choroid complex of guinea pigs with lens-induced myopia in vivo.

Zonula occludens-1 (ZO-1) and occludin are important tight junction (TJ)-associated proteins, which are expressed in the retinal pigment epithelium (RPE)-choroid complex. Retinoic acid (RA) is a regulator of eye growth and may play an important role in forming functional TJs. The aim of this study was to detect the changes that occur in the expression of ZO-1 and occludin in the RPE-choroid complex of guinea pigs with lens-induced myopia (LIM), and to investigate the effect of RA on TJ-associated proteins in vivo. We developed an animal model of myopia by placing a -6.00 D negative lens on the right eyes of 3-week-old guinea pigs. The refractive error and axial length of the eye were measured on days 0, 3, 7 and 14. High-performance liquid chromatography (HPLC) was performed to detect the changes in endogenous RA in the RPE-choroid complex. The expression of ZO-1 and occludin was observed by immunofluorescence and assayed by western blot analysis. Additionally, 2 µl LE540 (2.5 µg/µl), an antagonist of RA receptors (RARs), was injected into the vitreous chamber of the eyes of guinea pigs with LIM and 2 µl phosphate-buffered saline (PBS) (2.5 µg/µl) were injected as a negative control. We observed no obvious change in RA, ZO-1 and occludin expression in the normal control group within 14 days. In the LIM and LIM plus PBS groups, the level of RA and the expression of ZO-1 and occludin in the RPE-choroid complex significantly increased within 14 days along with the development of myopia. However, the level of RA was inhibited and the expression of TJ-associated proteins decreased in the eyes of guinea pigs with LIM following the injection of LE540. Thus, we consider that the expression of ZO-1 and occludin is increased in the RPE-choroid complex during the development of myopia. This change in expression may be regulated by RA, a factor known to be involved in the regulation of eye growth.

Mechanism of the DL-alpha-aminoadipic acid inhibitory effect on form-deprived myopia in guinea pig.

AIM: To investigate the effect of intravitreal injection of DL-alpha-aminoadipic acid (DL-α-AAA) on ocular refractive state and retinal dopamine, transforming growth factor-ß2 (TGFß2), vasoactive intestinal polypeptide (VIP) in guinea pig form-deprived myopia. METHODS: Four-week-old pigmented guinea pigs were randomly assigned to 4 groups: normal control, deprivation, deprivation plus DL-α-AAA, deprivation plus saline. Form deprivation was induced with the self-made translucent eye shields, and lasted for 14 days. 8µg DL-α-AAA was injected into the vitreous chamber of deprived eyes. The corneal radius of curvature, refraction and axial length were measured. Retinal dopamine content was evaluated by the high-performance liquid chromatography with electrochemical detection, and TGFß2 and VIP protein were detected by Western blotting. RESULTS: Fourteen days of eye occlusion caused the axial length to elongate and become myopic in the form-deprived eyes, with the decrease of retinal dopamine and the increase of TGFß2 and vasoactive intestinal polypeptide (VIP) protein. Intravitreal injection of DL-α-AAA could inhibit the myopic shift from (-3.65±1.06)D to (-1.48±0.63)D, P<0.01 due to goggles occluding and cause the decrease of retinal TGFß2 protein in the deprived eyes. However, intravitreal injection of DL-α-AAA had no significant effect on retinal dopamine and VIP protein in deprived eyes. Retinal TGFß2 protein correlated highly with the ocular refraction (y=-3.34+0.31/x, F=74.75, P<0.001) and axial length (y=8.39-0.02/x, F=48.32, P<0.001) in different treatment groups. CONCLUSION: Intravitreal injection of DL-α-AAA is effectively able to suppress the development of form deprivation myopia, which may be associated with retinal TGFß2 protein in guinea pigs.

Bilateral optical nerve atrophy secondary to lateral occipital lobe infarction.

PURPOSE: To report a phenomenon of optical nerve atrophy secondary to lateral occipital lobe infarction. METHODS: Two successive patients with unilateral occipital lobe infarction who experienced bilateral optical nerve atrophy during the follow-up underwent cranial imaging, fundus photography, and campimetry. RESULTS: Each patient was diagnosed with occipital lobe infarction by cranial MRI. During the follow-up, a bilateral optic atrophy was revealed, and campimetry showed a right homonymous hemianopia of both eyes with concomitant macular division. CONCLUSION: Bilateral optic atrophy was related to occipital lobe infarction, and a possible explanation for the atrophy was transneuronal degeneration caused by occipital lobe infarction.

[MK801 controls form-deprivation myopia by nitric oxide-cyclic GMP signaling pathway in guinea pig].

OBJECTIVE: To investigate the mechanism of myopia following intravitreous injection of MK801 (dizocipine maleate) intravitreous injected. METHODS: Three-week-old guinea pigs were divided into six groups: group A (control), group B (3 weeks form-deprivation in right eye), group C ( 3 weeks form-deprivation in right eye + saline), group D (3 weeks form-deprivation in right eye + MK801 1ng), group E (3 weeks form-deprivation in right eye + MK801 10 ng), group F (3 weeks form-deprivation in right eye + MK801 100 ng). The refraction and axial length of the eyes were measured. ncNOS was measured by hybridization in situ, and cyclic GMP (cGMP) concentrations by radioimmunochemistry. The correlation between MK801 concentration and diopter degree, axial length of the eyes, and levels of ncNOS or cyclic GMP were analyzed with linear correlation in the groups C-F. RESULTS: Diopter degree was decreased, axial eye length was shorted and levels of ncNOS and c-GMP were decreased in groups C, D, E and F dependent on the concentration of MK801. The diopter degree had positive correlation with MK801 concentration (r=0.702, P<0.05), while the axial eye length and the levels of ncNOS and cGMP were negatively correlated (r=-0.736, -0.637, -0.725, P<0.05) CONCLUSION: MK801 injected into the vitreous humor can restrain myopia by down-regulated the expression of the nitric oxide-cyclic GMP signaling pathway. The effect is concentration dependent.

Retinoic acid metabolic change in retina and choroid of the guinea pig with lens-induced myopia.

AIM: To investigate the role of retinoic acid (RA) and retinaldehyde dehydrogenase-2 (RALDH(2)) of retina and choroid in the guinea pig lens-induced myopic eyes. METHODS: Totally 45 guinea pigs, at age of three weeks, were randomly assigned into three groups: the normal control, the lens-induced group and the recovering group. Out of focus was induced by the -6.00D concave lens on the left eye, and lasted for 15 days. All animals underwent biometric measurement (corneal radius of curvature, refraction and axial length). Subsequently, RA content in the retina and RPE/choriod complex was detected by reversed-phase high-performance liquid chromatography. RALDH(2) protein in the retina and RPE/choriod complex was evaluated by the immunohistochemical staining and Western blotting. RESULTS: After wearing -6.00D lens for 15 days, axial length of the lens-induced eye extends and myopia was formed, with RA contents increasing in both the neural retina and RPE/choroid complex. Comparing with the lens-induced group, myopic degree significantly relieved, and its RA contents in both the neural retina and RPE/choroid complex decreased in the recovering group. In the normal control, RALDH(2) protein was expressed positively in the retinal nerve fiber layer (RNFL), inner plexiform layer (IPL) and lateral border of outer nuclear layer (ONL). Retinal RALDH(2) protein increased in the lens-induced group, and was also positive in the outer plexiform layer (OPL). In the recovering group, retinal RALDH(2) protein attenuated the expression in the OPL turns to negative. RALDH(2) protein was not expressed in the choroid of any group. CONCLUSION: RA of retina and chorid participates in the regulation of the lens-induced myopia in guinea pigs, which may be related with retinal RALDH(2) protein.

Exogenous levodopa increases the neuro retinal dopamine of guinea pig myopic eyes in vitro.

PURPOSE: In our previous work, it has been shown that intraperitoneal injection of L-DOPA can inhibit the development of occlusion myopia in guinea pigs, and increase levels of retinal dopamine. The aim of this study was to investigate whether exogenous L-DOPA can be converted into dopamine in cultured retina of guinea pig eyes subjected to visual deprivation, and to evaluate whether müller cells are involved in the processing of retinal dopamine induced by L-DOPA. METHODS: Fifty-eight guinea pigs were randomly divided into 2 groups at the age of 4 weeks: normal control and visual deprivation. Form deprivation was induced with translucent eye shields over the right eye, and lasted for ten days. Corneal curvature, refraction and axial length were measured in all animals. In vitro, neuro-retina and müller cell were cultured, and L-DOPA was added to the culture medium at three concentrations: 1цM, 10цM and 100цM. Subsequently, dopamine content was evaluated by high-performance liquid chromatography, and apoptotic cells were identified by TUNEL staining. RESULTS: Ten days of occlusion caused the affected eyes to elongate and become myopic in guinea pigs. Compared with the deprivation group, 10цM L-DOPA treament significantly raised dopamine content in cultured retina and müller cells (P<0.05). However, 1цM and 100цM L-DOPA treatment caused no increase in dopamine levels (P>0.05). Apoptotic nuclei were detected in the ganglion cell layer (92.5%±8.3%) and inner nuclear layer (46.8%±9.1%) of cultured retina treated with 100 цM L-DOPA. Moreover, 100 цM L-DOPA also caused apoptosis of retinal müller cells, at a mean rate of 59.4 ±11.3%. CONCLUSION: Our results suggest that exogenous L-DOPA can cause an increase in retinal dopamine in form-deprived guinea pig eyes in vitro, and that müller cells are involved in the increase in retinal dopamine.

[Expression of cyclic guanine monophosphate and the ultrastructure change in retina of guinea pig with form-deprivation myopia].

OBJECTIVE: To explore the expression of cyclic guanine monophosphate (cGMP) and the ultrastructure change in retina of guinea pig with form-deprivation myopia and the underlying mechanisms. METHODS: Three-weeks-old guinea pigs were distributed in 3 groups: an untreated group (Group I), a myopia 2-weeks group (Group II) and a myopia 3-weeks group (Group III), animals underwent monocular form-deprivation by facemask for 2 and 3 weeks. The right eyes were deprived and the left eyes were self-controlled. The refraction and axial length of the eyes was measured. Retina was observed by electron microscope. The expression of cGMP was detected by radioimmunochemistry. RESULTS: Deprived eyes in guinea pig showed significant development of myopia, the refraction and axial length was increased. The pathological changes in ultrastructure of retina were aggravated with the development of myopia. The expression of cGMP was significantly up-regulated in the deprived eyes compared with self-control eyes(P<0.05). CONCLUSION: Form-deprivation can up-regulate the expression of cyclic GMP, which might play an important role in the development of myopia.

Modulation of TGFß(2) and dopamine by PKC in retinal Müller cells of guinea pig myopic eye.

AIM: To investigate the effect of protein kinase C (PKC) on transforming growth factor-ß(2) (TGFß(2)) and dopamine in retinal Müller cells of guinea pig myopic eye. METHODS: Myopia was induced by translucent goggles in guinea pig, whose retinal Müller cells were cultured using the enzyme-digesting method. Retinal Müller cells were divided into 5 groups: normal control, myopia, myopia plus GF109203X, myopia plus PMA, myopia plus DMSO. PKC activities were detected by the non-radioactive methods. TGFß(2) and tyrosine hydroxylase (TH) proteins were analyzed by Western Blotting in retinal Müller cells. Dopamine was determined by the high-performance liquid chromatography-electrochemical detection in suspensions. RESULTS: After 14 days deprived, the occluded eyes became myopic with ocular axle elongating. Müller cells of guinea pigs were obtained using enzyme digestion. Compared with normal control group, the increase in PKC activity and the up-regulation in TGFß(2) expression were found in retinal Müller cells of myopic eyes, with the decrease of TH and dopamine content (P<0.05). After PKC activated by PMA, TGFß(2) and TH content were up-regulated with the increase of dopamine content (P<0.05). While the PKC activities was inhibited by GF109203X, proteins of TGFß(2) and TH were down-regulated in the myopic eyes, with the decrease of dopamine content (P<0.05). CONCLUSION: TGFß(2) and dopamine are modulated by PKC in Müller cells of the myopic eyes in guinea pig.