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PURPOSE: Distinguishing an iris melanoma from an iris nevus can be challenging as few clinical features other than documented growth are helpful in making the diagnosis. In this study, we compared the presenting intraocular pressure (IOP) and cup-to-disc ratio (CDR) between affected and unaffected eyes in patients with iris melanoma and iris nevus. PATIENTS AND METHODS: This was a single-institution retrospective case series of patients treated for iris melanoma and iris nevus from January 2013 to October 2022. Thirty-nine subjects with iris melanoma and forty age-matched patients with iris nevus were included. We analyzed the difference in IOP, CDR, and diagnosis of glaucoma between affected and unaffected eyes in patients with iris melanoma and control iris nevus cohort. RESULTS: The average IOP for eyes with iris melanoma and iris nevus was 18.8±6.1 mmHg and 14.6±3.5 mmHg (P

Purpose: Distinguishing an iris melanoma from an iris nevus can be challenging as few clinical features other than documented growth are helpful in making the diagnosis. In this study, we compared the presenting intraocular pressure (IOP) and cup-to-disc ratio (CDR) between affected and unaffected eyes in patients with iris melanoma and iris nevus. Patients and methods: This was a single-institution retrospective case series of patients treated for iris melanoma and iris nevus from January 2013 to October 2022. Thirty-nine subjects with iris melanoma and forty age-matched patients with iris nevus were included. We analyzed the difference in IOP, CDR, and diagnosis of glaucoma between affected and unaffected eyes in patients with iris melanoma and control iris nevus cohort. Results: The average IOP for eyes with iris melanoma and iris nevus was 18.8± 6.1 mmHg and 14.6± 3.5 mmHg (P< 0.001), respectively. The average CDR was 0.36± 0.27 and 0.24± 0.14 (P=0.02), respectively. The average IOP of the contralateral unaffected eye in iris melanoma patients was 16.3± 3.5 mmHg, significantly less than the affected eye (P=0.03). The average CDR of the contralateral unaffected eye in iris melanoma was 0.25± 0.15, which was trending towards being less than the affected eye (P=0.05). There was no difference in the average IOP (P=0.89) or average CDR (P=0.49) between the affected and unaffected eye in patients with iris nevus. Conclusion: We demonstrate that patients with iris melanoma are more likely to have greater IOP and CDR in the affected eye compared to the unaffected eye, and a diagnosis of unilateral glaucoma than eyes with iris nevus. Patients with iris melanoma had greater IOP asymmetry between the affected and unaffected eye. Therefore, IOP and CDR asymmetry may suggest a diagnosis of iris melanoma. [ABSTRACT FROM AUTHOR]

Recent studies suggest that a shared neural ensemble may link distinct memories encoded close in time. According to the memory allocation hypothesis, learning triggers a temporary increase in neuronal excitability that biases the representation of a subsequent memory to the neuronal ensemble encoding the first memory, such that recall of one memory increases the likelihood of recalling the other memory. Here we show in mice that the overlap between the hippocampal CA1 ensembles activated by two distinct contexts acquired within a day is higher than when they are separated by a week. Several findings indicate that this overlap of neuronal ensembles links two contextual memories. First, fear paired with one context is transferred to a neutral context when the two contexts are acquired within a day but not across a week. Second, the first memory strengthens the second memory within a day but not across a week. Older mice, known to have lower CA1 excitability, do not show the overlap between ensembles, the transfer of fear between contexts, or the strengthening of the second memory. Finally, in aged mice, increasing cellular excitability and activating a common ensemble of CA1 neurons during two distinct context exposures rescued the deficit in linking memories. Taken together, these findings demonstrate that contextual memories encoded close in time are linked by directing storage into overlapping ensembles. Alteration of these processes by ageing could affect the temporal structure of memories, thus impairing efficient recall of related information.

We asked whether hyperoxia might induce hypomyelination of the corpus callosum, clinically described as periventricular leukomalacia (PVL) of the severely preterm infant. Mouse pups and their nursing dams were placed in 80% oxygen from P4-P8, then removed to room air until P11. Corpus callosal sections were probed myelin immunofluorescence, tested for myelin basic protein concentration by Western blot, and both glial fibrillary acidic protein levels and apoptosis quantified. Density of corpus callosal capillaries were measured after lectin staining and hypoxia measured by Hypoxyprobe. Numbers of oligodendrocytes were quantified by immunohistochemistry. We next used hypoxiamimesis as a surrogate to hypoxia by comparing cerebral hypoxia inducible factor (HIF) stabilization to hepatic HIF stabilization. Hyperoxia induced hypomyelination and a reduction of corpus callosal capillaries. Hyperoxia decreased numbers of oligodendrocytes with an increase in corpus callosal fibrosis and apoptosis. Cerebral hypoxiamimesis induced hypomyelination whereas hepatic hypoxiamimesis alone increased myelination, oligodendrocyte numbers, and corpus callosal capillary density. Hepatic HIF-1 dependence on myelination was confirmed using the cre/lox hepatic HIF-1 knockout. These findings suggest that hyperoxia can induce hypomyelination through vasoobliteration and subsequent ischemia, adding a potential oxygen induced mechanism to the diverse causes of periventricular leukomalacia of the severely preterm infant. Targeting hepatic HIF-1 alone led to increased myelination. [ABSTRACT FROM AUTHOR]

Southwest China has a high burden of spinal tuberculosis (TB). Few large case studies of spinal TB in southwest China have been conducted. This study investigated the features of 921 patients who were treated for spinal TB at a general hospital in southwest China between 2001 and 2016. Demographic data, clinical data, laboratory data, imaging findings, treatment methods, and outcomes of patients who were admitted to the hospital for spinal TB were reviewed retrospectively. The annual incidence of spinal TB increased throughout the study period. The greatest number of patients were 41 to 50 years old (22.04%). Local pain was the most common symptom (97.8%). A significant difference in the duration of symptoms was observed between rural populations (28.40 months) and urban populations (10.17 months) (P=.041). Of the patients, 32.68% had a normal erythrocyte sedimentation rate and 25.84% had a normal C-reactive protein level. The lumbar spine was the most commonly involved spinal site (44.77%), followed by the thoracic spine (43.60%). All of the patients underwent chemotherapy, and 77.10% of patients underwent surgery. Most of the patients were cured, with the exception of 2.19% of patients who discontinued chemotherapy after early improvement of clinical status. Spinal TB is still a major public health problem in southwest China. Chemotherapy and surgery can yield satisfactory outcomes with timely diagnosis and long-term treatment. It is urgent to increase the attention paid to spinal TB and improve knowledge of this disease among the general public, especially in southwest China. [Orthopedics. 2017; 40(6):e1017-e1023.]. [ABSTRACT FROM AUTHOR]