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The Institute of Physiology of the Czech Academy of Sciences (CAS) has been involved in the field of chronobiology, i.e., in research on temporal regulation of physiological processes, since 1970. The review describes the first 35 years of the research mostly on the effect of light and daylength, i.e., photoperiod, on entrainment or resetting of the pineal rhythm in melatonin production and of intrinsic rhythms in the central biological clock. This clock controls pineal and other circadian rhythms and is located in the suprachiasmatic nuclei (SCN) of the hypothalamus. During the early chronobiological research, many original findings have been reported, e.g. on mechanisms of resetting of the pineal rhythm in melatonin production by short light pulses or by long exposures of animals to light at night, on modulation of the nocturnal melatonin production by the photoperiod or on the presence of high affinity melatonin binding sites in the SCN. The first evidence was given that the photoperiod modulates functional properties of the SCN and hence the SCN not only controls the daily programme of the organism but it may serve also as a calendar measuring the time of a year. During all the years, the chronobiological community has started to talk about “the Czech school of chronobiology”. At present, the today´s Laboratory of Biological Rhythms of the Institute of Physiology CAS continues in the chronobiological research and the studies have been extended to the entire circadian timekeeping system in mammals with focus on its ontogenesis, entrainment mechanisms and circadian regulation of physiological functions. [ABSTRACT FROM AUTHOR]

• Outcomes following chemo-radiotherapy for pineal germinoma are excellent. • Multidisciplinary care optimises the diagnosis and treatment of pineal germinoma. • The utility of biomarkers and immunotherapy in germinoma remains uncertain. Pineal germinoma is rare with high cure rates following craniospinal radiotherapy. Efforts to reduce the radiotherapy dose and field via combination with chemotherapy suggest comparable disease control and reduced neurocognitive impairments, while the efficacy of immunotherapy in pineal germinoma remains undetermined. This report aimed to review clinical outcomes in patients treated for pineal germinoma in Queensland, Australia, and assess for Programmed Death-Ligand1 (PD-L1) expression. Patients who commenced radiation and/or chemotherapy for pineal germinoma from 2005 to 2017 were retrospectively identified using Queensland Oncology Online database. Demographic, diagnostic, treatment, and outcome data was obtained from electronic medical records. PD-L1 immuno-histochemistry was performed on available specimens. Eighteen patients with long-term follow-up data were identified. Median age at diagnosis was 16.8 years (range 9–46 years). Diagnosis was made histologically in fifteen patients, and radiologically in three. All patients underwent radiotherapy (median 36 Gy (range 21–54 Gy)) with lower median dose delivered with whole ventricle irradiation (12/18patients) than craniospinal irradiation (5/18patients). Sixteen patients received chemotherapy preceding radiotherapy. All patients are alive at median 7.25 years from primary treatment completion (range 2.03–13.1 years). Relapse occurred in three patients (16.67%) following treatment response, all of whom achieved remission following high-dose chemotherapy with stem-cell support and craniospinal radiotherapy. Post-treatment functional outcomes were similarly excellent. PD-L1 expression was low (1–49% cells) or negative in 87% of tumours tested but results were confounded by specimen quality and availability. Reduced-dose radiotherapy with chemotherapy does not compromise outcome and is standard of care at this institution. Immunotherapy is unlikely to become standard treatment in the near future. [ABSTRACT FROM AUTHOR]

• Pathological tumors originating purely from the pineal gland are very rare, which mainly found in children and adolescents. • Clinical manifestations of pineal tumor mosty: visual impairment, headaches, and a decrease of cognitive and consciousness. • It is recommended to install VP-shunt several days before definitive tumor surgery for ventricular decompression. • The choice of technique is determined by the tumor location, pathological findings, and risk of complications. • The OTA technique allows excellent views of pineal region, and access to the midline, superior vermis, and ventricle III. The development of improved micro-surgery techniques and neuroanesthesia has become increasingly sophisticated makes open-microsurgery tumor resection a choice for the management of the pineal region. An 11-year-old male with a pineal body tumor post ventriculo-peritoneal (VP) shunt, underwent tumor resection. Patients complain of headaches, relieve with medication but often recurrent, and often experience a decrease in consciousness. One month before the procedure, the patient experienced blurred vision, staggering, nausea, vomiting, and decrease of consciousness. The operation is performed with an occipital transtentorial approach (OTA) technique. During surgery, hemodynamics was relatively stable. Postoperatively, the patient underwent controlled ventilation in the intensive care room, and recover significantly within one week. Various surgical approaches have been proposed for pineal region tumors. We review the available literature (PubMed) with 11 reported cases of pineal tumor therapy with the occipital transtentorial approach and evaluate general symptoms in clinical manifestations, histopathological features, radiological findings, and survival times to demonstrate therapeutic effectiveness. Several cases of the pineal tumor were also reported using tumor extraction by occipital transtentorial approach. The choice of approach is influenced by the location of the tumor, pathology findings, the neurosurgeon's comfort and consideration of the risk of complications. [ABSTRACT FROM AUTHOR]

• We present a unique case of a large falcotentorial meningioma manifesting only with subtle abducens nerve paresis. • Management of these uncommon lesions remains challenging despite modern day surgery. • Complete surgical resection is the definitive therapeutic option but is associated with significant potential morbidity. • Cerebrospinal fluid diversion without resection may be advocated in certain cases, particularly if relatively asymptomatic. We report the case of a falcotentorial meningioma presenting only with binocular, horizontal diplopia in an otherwise healthy sixty-two-year old male. Review of the established literature highlights a lack of consensus regarding management of this extremely rare pineal region tumor. Complete surgical resection ultimately remains the ideal therapeutic option but surgical excision continues to bear serious risk of neurologic and ophthalmic morbidity, including hemianopia and cortical visual impairment. We advocate that a multidisciplinary approach focusing on patient values is critical in treatment of these uncommon lesions. Cerebrospinal fluid diversion in this patient achieved successful resolution of symptoms secondary to intracranial hypertension whilst facilitating close surveillance. [ABSTRACT FROM AUTHOR]

Abstract: VITOM-90 (Karl Storz Endoscopy, Tuttlingen, Germany) is a new technology that can be used as an alternative to the operating microscope. We have found that this device substantially improves surgeon comfort during infra-tentorial supracerebellar approaches to pineal region masses, and now report our experiences. The VITOM-90 is a specially designed scope that is attached to a high definition (HD) digital camera and displayed on a HD video monitor. This system was utilized in five patients undergoing infratentorial supracerebellar approaches for pineal region lesions. Surgical outcomes and pathologies are described. The device was used by three surgeons during five procedures. Three patients underwent surgery in the sitting position and two in the modified prone (Concorde) position. Pathologies included pineocytoma, lipoma, and germinoma. Total resection was achieved in three patients and subtotal in two patients. Surgeon assessment was positive; surgeons indicated that surgery with the VITOM-90 was more comfortable than with the operating microscope. Lack of stereopsis was considered a minor drawback. The VITOM-90 permitted a natural head and neck position. Operating room personnel and residents reported improved visualization of the anatomy. Using the VITOM-90 benefited surgeons during pineal region surgery by reducing strain and allowing the surgeon to operate from a comfortable position without increased operative time or complications. The improved comfort levels may translate into safer, more accurate surgeries in this complex area. [Copyright &y& Elsevier]

Copyright of Revista Española de Patología is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Schwannomas arising from the trochlear nerve are very rare and to our knowledge, less than 35 histologically documented cases have been reported in the literature. There are no reports of a schwannoma in the pineal region. We report a 24-year-old woman who underwent a para-occipital trans-tentorial approach and gross total excision of a pineal region schwannoma arising from the trochlear nerve. This is the first such reported case. [ABSTRACT FROM AUTHOR]

Summary: Organic cation transporter 3/4 (OCT3/4) is a transcription factor of embryonic stem cells; c-kit (CD117) is a tyrosine kinase receptor implicated in seminoma carcinogenesis. Their reactivity is well characterized in testicular, but not extragonadal and metastatic, germ cell tumors. A total of 93 germ cell tumors (41 seminoma, 22 embryonal carcinoma, 18 teratoma, and 12 yolk sac tumor) were obtained from the central nervous system (30), mediastinum (23), retroperitoneum/abdomen (31), and other locations (9). Immunohistochemical staining for c-kit, placental-like alkaline phosphatase (PLAP), OCT3/4, and new markers D2-40 and AP-2γ was performed on seminomas; CD30 and epithelial membrane antigen were added for nonseminomas. In embryonal carcinoma, c-kit reacted in 17 of 22 cases, OCT3/4 in 18 of 22, and PLAP in 13 of 22. OCT3/4 was superior to PLAP in intensity and percent cells staining. In seminoma, OCT3/4 and D2-40 were superior to PLAP in intensity and percent cells; c-kit and AP-2γ were superior in percent cells. D2-40 stained 23 of 24 seminomas strongly but had only weak focal reactivity in 6 of 17 embryonal carcinomas. Sensitivity and specificity were high for OCT3/4 discriminating seminoma and embryonal carcinoma, and c-kit discriminating seminoma, from other germ cell tumors. For embryonal carcinoma, OCT3/4 had higher specificity (0.94) than CD30 (0.786) owing to CD30 reactivity in 3 of 10 teratomas. Epithelial membrane antigen discriminated teratoma from other nonseminomas with a sensitivity of 1 but reacted occasionally in embryonal carcinoma (3/15) and yolk sac tumor (2/7). In conclusion, for extragonadal seminoma, OCT3/4, AP-2γ, D2-40, and c-kit were equivalently superior to PLAP. For embryonal carcinoma, OCT3/4 was superior to PLAP and more specific than CD30. D2-40 is recommended to discriminate between seminoma and embryonal carcinoma. [Copyright &y& Elsevier]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing urbanisation is altering the physiology of wild animals and the mechanisms involved are largely unknown. We hypothesised that altering the physiology of urban organisms is due to the effect of extra light at night on the circadian clock by modulating the expression of pineal machinery and clock genes. Two experiments were performed. In Experiment 1, immediately after being procured from their respective sites (urban and rural sites), birds were released individually in LL dim light conditions. Circadian rhythm period, activity duration, and total activity count were calculated and did not differ between urban and rural birds. In Experiment 2, birds (from urban and rural habitats) were sampled at six time points at regular 4-h intervals, beginning 1 h after sunrise. We measured daily variations in plasma melatonin levels. We also analysed the expression levels of Aanat , Mel1A and Mel1B as an indicator of melatonin biosynthesis and action machinery. Clock and clock-controlled genes (Bmal1 , Clock , Per2 , Per3 , Cry1 and Npas2) were studied in the hypothalamus, the pineal gland, and retina to investigate the effects of urban habitats on the circadian clock. Our results show that there is a lower expression of Aanat in the pineal gland and relatively low plasma melatonin levels in urban birds. Further, clock genes are also differentially expressed in all three central tissues of urban birds. We propose that alterations in the melatonin biosynthesis machinery and the expression of clock genes could result in miscalculations in the internal timing of the organism, with environmental timings leading to altered physiology in urban wild animals. Image 1 • There is a daily expression of clock and clock controlled genes in both urban and rural habitats. • Aanat expression is lower in the pineal gland in urban birds. • Plasma melatonin secretion is delayed and levels are low in urban birds. • Clock genes are also differentially expressed in all three central tissues of urban birds. • We propose urban environment alters daily clock expression leading to miscalculations of internal timing hence altered urban physiology. Present finding suggest that there is lower secretion of melatonin and altered expression of clock genes in urban birds. [ABSTRACT FROM AUTHOR]