Immunocytochemical localization of GABAA receptors in goldfish and chicken retinas

A monoclonal antibody (mAb 62-3G1) to the GABAA receptor/benzodiazepine receptor/Cl- channel complex from bovine brain was used with light and electron microscopy in goldfish retina and light microscopy in chicken retina to localize GABAA receptor immunoreactivity (GABAr-IR). GABAr-IR was found in the outer plexiform layer (OPL) in both species, in three broad bands in the inner plexiform layer (IPL) of goldfish, and in seven major bands of the chicken IPL. A small percentage of amacrine cell bodies (composing at least three types) were stained in chicken. In goldfish OPL, GABAr-IR was localized intracellularly and along the plasma membrane of cone pedicles, whereas rod spherules were lightly stained, but always only intracellularly. In chicken, all three sublayers of the OPL were GABAr-IR. The presence of GABAr-IR on photoreceptor terminals is consistent with data indicating feedback from GABAergic horizontal cells to cones. In the goldfish IPL, GABAr-IR was localized to postsynaptic sites of amacrine cell synapses; intracellular staining of processes in the IPL also was observed in presumed "GABAergic" targets. A comparison of GABAr-IR with the distributions of 3H-muscimol uptake/binding, glutamate decarboxylase-IR, GABA-IR, and 3H-GABA uptake in the IPL showed either a reasonable correspondence or mismatch, depending on the marker, species, and lamina within the IPL. The distribution of GABAr-IR in the retina corresponded better with the 3H-muscimol than with 3H-benzodiazepine binding patterns yet overall was in excellent agreement with many other physiological and anatomical indicators of GABAergic function. We suggest that intracellular GABAr-IR represents the biosynthetic and/or degradative pathway of the receptor and we conclude that mAb 62-3G1 is a valid marker of GABAA receptors in these retinas and will serve as a useful probe with which to address the issue of mismatches between the localization of GABAA receptors and indicators of presynaptic GABAergic terminals.     

Ubiquitinated neurites are associated with preamyloid and cerebral amyloid β deposits in patients with hereditary cerebral hemorrhage with amyloidosis Dutch type

Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.)     

Endovascular repair of abdominal aortic aneurysm in a renal transplant patient

A 65-year-old man presented with an asymptomatic infrarenal abdominal aortic aneurysm of 6 cm in transverse diameter. Five years before he received a cadaveric renal transplant. The patient also had the following risk factors and associated diseases: arterial hypertension, coronary artery disease, previous myocardial infarction, coronary angioplasty and stent, ileal resection secondary to Chron disease, hepatopathy, hyperlipidemia and hepato-renal cystic disease. The ASA classification was III, IV. Considering previous abdominal operations and risk factors, we decided to repair the aneurysm with a minimal aggression. The aneurysm was successfully approached by an endovascular route implanting a 22x10 bifurcated aorto-iliac endovascular prosthesis. The patient died 13 months later after being diagnosed of enterocolitis by cytomegalovirus complicated with sepsis and lung infection. We consider this less invasive modality of treatment a valid and useful alternative in this high-risk group of patients.     

Amyloidosis and Alzheimer's disease

Alzheimer's disease (AD) is the most frequent type of amyloidosis in humans and the commonest form of dementia. Extracellular Abeta amyloid deposits in the form of amyloid plaques and cerebral amyloid angiopathy as well as intraneuronal neurofibrillary tangles co-exist in the brain parenchyma of AD patients, the cognitive areas being the most severely affected. This review focuses on the potential role of amyloid in the development of neurodegeneration and presents studies of AD and other unrelated inherited dementia syndromes associated with neuronal loss and amyloid deposition in the brain.     

Chondrosarcoma of the uterus: case report and literature review

BACKGROUND: Pure heterologous sarcomas of the uterine corpus are extremely rare, accounting for 4% of all uterine sarcomas. Primary chondrosarcoma, which is characterized by the absence of epithelial or other heterologous mesenchymal elements, is included in this group. To this date, only 17 cases, including the presenting case, have been reported. CASE: A 55-year-old female presenting with post-menopausal bleeding was diagnosed with chondrosarcoma of the uterus, after abdominal hysterectomy and bilateral salpingoophorectomy. After 8 months of surgery, there is no evidence of recurrence after receiving external radiotherapy and brachytherapy. CONCLUSION: Primary chondrosarcoma of the uterus is an extremely rare uterine tumour most frequently diagnosed by the pathologist. They are usually aggressive malignant tumours with an early relapse and metastases.