Treatment of Pituitary Carcinomas and Atypical Pituitary Adenomas: A Review

Atypical pituitary adenomas (APAs) are aggressive tumors, harboring a Ki-67 (MIB-1) staining index of 3% or more, and positive immunohistochemical staining for p53 protein, according to the World Health Organization (WHO) classification in 2004. Pituitary carcinomas (PC) usually develop from progressive APAs and predominantly consist of hormone-generating tumors, defined by the presence of disseminations in the cerebrospinal system or systemic metastases. Most of the cases with these malignant pituitary adenomas underwent surgeries, irradiations and adjuvant medical treatments, nevertheless, the therapies are mainly palliative. Recently, the efficacy of temozolomide (TMZ), an orally administered alkylating agent, has been reported as an alternative medical treatment. However, some recent studies have demonstrated a significant recurrence rate after effective response to TMZ. Further clinical and pathological researches of malignant pituitary adenomas will be required to improve the outcome of patients with these tumors.     

Cerebral excitability in pup rats prenatally exposed to 1-bromopropane is suppressed by bromide accumulated in the brain

Previously, we reported that prenatal exposure to 1-bromopropane (1-BP) causes the accumulation of bromide (Br^-) in the brain of rat pups. Here, we aimed to investigate the effects of Br^- accumulation in rat pups prenatally exposed to 1-BP vapor. Dam rats were exposed to 1-BP (400 or 700 ppm; 1-BP group) by inhalation, or to NaBr (20 mM; Br^- group) in drinking water during gestation days 1–20. We also analyzed pentylenetetrazole (PTZ, 60 mg/kg, ip)-induced behavioral changes in pups prenatally exposed to 1-BP or Br^- on postnatal day (PND) 14. PTZ-induced epileptic convulsions were inhibited in both 1-BP (700 ppm) and Br^- groups. The inhibition of neuronal excitability induced by Br^- was evaluated electrophysiologically using the hippocampal slices obtained from PND14–16 pups. PTZ (2 mM) failed to induce epileptiform discharge in the presence of 1.2 mM Br^- in the slices obtained from the control group. However, it induced epileptiform discharge following the removal of Br^-, by perfusing artificial cerebrospinal fluid into the slices obtained from the Br^- group. Our results indicate that Br^- accumulates in the brain of neonatal rat pups prenatally exposed to 1-BP vapor suppressed neuronal excitability.     

Protective effects of cyclodextrin sulphates against gentamicin-induced nephrotoxicity in the rat

Abstract— The effects of cyclodextrin sulphates on the development of rat renal dysfunction induced with gentamicin, an aminoglycoside antibiotic, were studied. Daily subcutaneous injection of gentamicin (100 mg kg^?1, 14 days) developed nephrotoxicity in the rat as assessed by an increase in serum urea nitrogen and histopathological changes in the renal cortex. When cyclodextrin sulphates were given intraperitoneally at 300 mg kg^?1 at 6 h intervals after gentamicin administration, they protected the rat against the drug-induced renal impairment, while the parent cyclodextrins were ineffective. Since post-administration of cyclodextrin sulphates did not reduce the total amount of gentamicin accumulated in the kidney, the protection may occur through interference with intracellular events leading from the drug accumulation to nephrotoxicity. These results suggest that cyclodextrin sulphates are particularly effective in preventing renal failure associated with aminoglycoside treatment.     

Ganglion cells in Ewing's sarcoma following chemotherapy: A case report

A case of Ewing's sarcoma of the bone, arising in the right radius of a 12-year-old girl, which showed unique histologic features after pre-operative treatment, is reported. The light microscopic features of a biopsy sample were those of a small round cell tumor showing positive immunoreaction with antibodies against the product of the MIC 2 gene (O13), neuron-specific enolase, neurofilament, and synaptophysin, but no morphological differentiation. The patient received combined intensive multi drug chemotherapy and radiation before surgery. Examination of the surgical specimen showed that the tumor was less cellular than that in the biopsy specimen, and was composed mainly of loosely textured large cells mimicking ganglion cells, occasionally forming Homer-Wright rosettes. An lmmunohistochemical study revealed that neural differentiation was enhanced. Immunoreactivity for Leu-7 also became positive. Although the patient underwent postoperative chemotherapy, she died of multiple lung and bone metastases 30 months alter the diagnosis. Autopsy showed that metastatic foci were made up of densely packed small round cells like those seen In the biopsy samples, but associated with prominent Homer-Wright rosettes. To the authors' knowledge, this is the first report of a tumor being replaced almost entirely by ganglion cells after preoperative chemotherapy and radiotherapy.     

Origin of neovascular structure in an early stage of hepatocellular carcinoma: Study of alpha-smooth muscle actin immunohistochemistry in serial thin sections of surgically resected cancer

Background: To elucidate the origin of the neovascular structure found in well‐differentiated hepatocellular carcinoma (HCC), an immunohistochemical study was performed on sequential thin section specimens. Method: Eleven surgically resected specimens of well‐differentiated HCC were analyzed for neovascular structure using monoclonal alpha‐smooth muscle actin (α‐SMA) antibody. Each paraffin specimen was serially sliced to a thickness of 3 µm for immunohistochemistry. When a ring‐shaped structure was found unrelated to portal triads on α‐SMA staining, it was regarded as abnormal neovascularity (non‐triadal vessel or unaccompanied vessel). Results: All of the 11 liver cancers had thin‐walled, round‐ or oval‐shaped non‐triadal vessels in their well‐differentiated parts. Immunohistochemistry of serial thin sections of HCC showed that these non‐triadal vessels were connected to portal veins in portal triads in well‐differentiated cancer in a total of nine patients (81.8%). This type of neovascular structure found in a well‐differentiated cancer seemed to be a surviving portal vein among diminishing and disappearing arteries and bile ducts. All 11 tumors showed isovascular staining on ordinary digital subtraction angiography, and four of the tumors showed negative enhancement on intra‐arterial carbon dioxide‐enhanced ultrasonography or computerized tomographic (CT) hepatic arteriography, suggesting a relative arterial blood scarcity in the tumor nodules. Conclusion: At an early stage of HCC, non‐triadal vessels originate from ordinary portal veins in intratumoral portal triads. This fact sufficiently explains the reason why a well‐differentiated liver cancer can sometimes show arterial blood paucity on CT arteriography or enhanced ultrasonography.     

Characterization of colonic motor activity in conscious dogs

Diurnal changes in canine colonic motility were investigated by means of chronically implanted force transducers. A characteristic of the colonic motor profile in the fasted state was the occurrence of colonic motor complexes consisting of tonic contractions superimposed with phasic ones. On feeding, motor complexes were immediately induced in the whole colon and continued to occur at significantly shorter intervals than those in the fasted state, but the duration and the amplitude of the colonic motor complexes were not affected by feeding. This increased activity period lasted for 8–16 h after feeding, and 83.3% of the defecations were observed in this period. Of the defecations 33% occurred in the first 2 h after feeding (P < 0.05). More than 80% of the giant migrating contractions associated with defecation propagated from the middle to the distal colon, and the start of faeces evacuation coincided with the end of the relaxation period of the distal colon preceding the arrival of the giant migrating contractions. More than 90% of the giant migrating contractions not associated with defecation migrated from the proximal to the middle colon. More than 60% of the colonic motor complexes migrated in an aboral direction and about 18% of them in an oral direction. These results suggest that (1) defecations tend to occur immediately after feeding; (2) the regional distribution of giant migrating contractions was different between those associated and not associated with defecation.     

Predictive factors in eradicating hepatitis C virus using a relatively small dose of interferon

Interferon (IFN) can reduce hepatitis C virus load and even eliminate the virus in 30-40% of patients. Several predictive factors for eradication of the virus have been reported and a higher dose of IFN tends to result in elimination of the virus. However, a small dose of IFN sometimes is as effective as a large dose in eradicating the virus. The predictive factors for such a response are not well established. We retrospectively analysed 50 patients with chronic hepatitis C who were treated with relatively small amounts of IFN (equal or less than 252 million units). Eleven patients were responders (elimination of hepatitis C virus (HCV) and normalization of alanine amino transferase (ALT) for at least 6 months), but the remaining 39 were non-responders. Multivariate analysis showed that the pretreatment viral load and total dose of IFN per kilogram of bodyweight were significant predictive factors of response to therapy. We also assessed the amino acid substitutions in the IFN sensitivity determining region (ISDR), NS5A codon 2209-2248, of HCV in serum samples obtained from 31 patients with HCV genotype 1 b. The presence of more than one amino acid substitution in the ISDR tended to correlate with HCV genotype lb elimination. As IFN is expensive and has a number of serious side effects, our study suggests that the optimal dose of IFN may vary from one patient to another and that more stringent criteria should be used to select the optimal dose for therapy.     

Inhibition of platelet adhesion to collagen by monoclonal anti-CD36 antibodies

Monoclonal anti CD36 antibodies capable of inhibiting platelet adhesion to collagen have not previously been identified. We have now prepared two groups of monoclonal antibodies. One group was prepared using, as immunogen, highly purified (99+%) CD36 prepared by a denaturing procedure. These antibodies (Mo series) reacted strongly with CD36 on protein blots but did not immunoprecipitate native CD36 from platelet lysates nor inhibit platelet adhesion to collagen. The second group of monoclonal antibodies (131 series) was prepared using CD36 purified to >95% by a non-denaturing procedure. These antibodies reacted with control platelets, but not Nak^a-negative platelets which lack CD36, as measured by flow cytometry and by immunoprecipitation. Three monoclonal antibodies of this latter group (131.4, 131.5 and 131.7) inhibited platelet adhesion to collagen in static systems under Mg²⁺-independent conditions but had little effect in the presence of Mg²⁺. 131.4 and 131.7 also inhibited adhesion to collagen using citrated whole blood in a parallel plate flow chamber at physiological shear rates (800 s^?1), whereas 131.5 was without effect. These are the first anti-CD36 monoclonal antibodies shown to be capable of inhibiting platelet adhesion to collagen and provide further evidence that CD36 plays a role in platelet–collagen interaction.     

amilial Primary Biliary Cirrhosis

A 53-year old male and his daughter (38 years old) had primary biliary cirrhosis. The daughter had a high titer of antimitochondrial and other autoantibodies. Nine members, including, four living sibs, mother and two of the daughter's healthy offspring have been examined for liver function, the presence of autoimmune antibodies, cell mediated immunity and histocompatibility antigens. The eldest and second sons, mother and sisters of the affected daughter had multiple autoimmune reactions including antismooth-muscle antibodies and decreased peripheral T lymphocyte but liver tests were normal except in the eldest son. Histocompatibility antigens HL-A9 and HL-B5 were present in both patients and the elder son.
Thus the findings suggest a similar genetic predisposition to immunologic abnormalities among the family members of the patients with primary biliary cirrhosis.