Morphology, cytochemistry and immunocytochemistry of the circulating granulocytes of the loggerhead sea turtle Caretta caretta

The eosinophils and heterophils of loggerheads display a similar rounded shape, an eccentric and elongated or slightly lobulated nucleus and a cytoplasm containing acidophilic pleomorphic granules. The characterization of the different types of granulocytes from nine Mediterranean loggerheads (Caretta caretta), based on cytochemical and immunocytochemical reactions and ultrastructural studies, is reported. On the basis of their positivity after myeloperoxidase, alkaline phosphatase and chloroacetate esterase reactions (typical of mammalian neutrophils), the granulocytes were classified as heterophils, while those myeloperoxidase-negative, major basic protein-positive granulocytes (like mammalian eosinophils), displaying a weak expression of interleukin 5 (a growth and differentiation factor, activator and chemoattractant for eosinophils), were classified as eosinophils. The immunocytochemical and TEM studies allowed the identification of these two granulocyte types, both of which show an eosinophilic reaction with May–Grünwald–Giemsa, periodic acid–Schiff and neutral red staining positivity.     

Hematological malignancies in chronic inflammatory bowel diseases: report of five cases and review of the literature

Several forms of primary and secondary hematological malignancies were rarely observed during the clinical course of inflammatory bowel diseases (IBD). Patients needing a prolonged treatment with immunosuppressants, such as azathioprine or methotrexate, with familiarity and genetic predisposition seem to be at a higher risk of leukemia. On the other hand, asthenia, thickness, and fever may be the symptoms of the onset of each kind of hematological malignancy. The finding of anemia, alteration of leukocyte count and large undetermined cells may suggest increased probability of abnormal proliferation of a single white blood cell line. In this report, the occurrence of hematological malignancies is described in five patients affected by IBD (three with ulcerative colitis and two with Crohn’s disease) attending our Gastroenterology Unit.     

A different schedule of zoledronic acid can reduce the risk of the osteonecrosis of the jaw in patients with multiple myeloma.

Osteonecrosis of the jaw (ONJ) is a reported complication of bisphosphonate use. The incidence ranges between 6 and 13% and seems to be higher in people treated with zoledronic acid (ZA) than with pamidronate. We retrospectively evaluated the incidences of ONJ and skeletal-related events (SRE) in 106 patients with multiple myeloma divided in two groups according to the schedule of administration of bisphosphonates: 51 received monthly administrations until tolerated (group A, standard schedule), 55 were treated monthly during the first year and then every 3 months (group B, reduced schedule). The incidence of SRE was similar (15.1 per 100 person years in group A and 17.7 in group B). ONJ occurred in seven patients, six in group A and one in group B (P=0.049). The risk of ONJ was eight-fold lower with the reduced schedule than with the standard schedule. The only significant risk factor for ONJ was the type of bisphosphonate (P=0.006). The incidence of ONJ was significantly higher with ZA than with pamidronate + ZA (9.1 vs 1.6 per 100 person-years). No ONJ was observed in patients treated only with pamidronate. A reduced schedule of ZA may be safer than the standard schedule while maintaining anti-resorptive efficacy.     

Effects of MDR1 and MDR3 P-glycoproteins, MRP1, and BCRP/MXR/ABCP on the transport of (99m)Tc-tetrofosmin

Multidrug resistance (MDR1) P-glycoprotein (Pgp), multidrug resistance-associated protein (MRP1), and breast cancer resistance protein (BCRP/MXR/ABCP) are members of the ATP-binding-cassette (ABC) superfamily of membrane transporters and are thought to function as energy-dependent efflux pumps of a variety of structurally diverse chemotherapeutic agents. We herein report the characterization of (99m)Tc-Tetrofosmin, a candidate radiopharmaceutical substrate of ABC transporters. (99m)Tc-Tetrofosmin showed high membrane potential-dependent accumulation in drug-sensitive KB 3-1 cells and low antagonist-reversible accumulation in MDR KB 8-5 and KB 8-5-11 cells in proportion to levels of MDR1 Pgp expression. In KB 8-5 cells, EC(50) values of the potent MDR antagonists N-(4-[2-(1,2,3, 4-tetrahydro-6,7-dimethoxy-2-isoquinolinyl)ethyl]-phenyl)-9, 10-dihydro-5-methoxy-9-oxo-4-acridine carboxamide (GF120918), (2R)-anti-5-?3-[4-(10, 11-difluoromethanodibenzo-suber-5-yl)piperazin-1-yl]-2 -hydroxypropoxy ?quinoline trihydrochloride (LY335979), and (3'-keto-Bmt')-[Val(2)]-cyclosporin A (PSC 833) were 40, 66, and 986 nM, respectively. Furthermore, only baculoviruses carrying human MDR1, but not MDR3, conferred both a decrease in accumulation of (99m)Tc-Tetrofosmin in host Spodoptera frugiperda (Sf9) cells and a GF120918-induced enhancement. Transport studies with a variety of stably transfected and drug-selected tumor cell lines were performed with (99m)Tc-Tetrofosmin and compared with (99m)Tc-Sestamibi, a previously validated MDR imaging agent. MDR1 Pgp readily transported each agent. To a lesser extent, MRP1 also transported each agent, likely as co-transport substrates with GSH; neither agent was a substrate for the BCRP/MXR/ABCP half-transporter. In mdr1a(-/-) and mdr1a/1b(-/-) mice, (99m)Tc-Tetrofosmin showed approximately 3. 5-fold greater brain uptake and retention compared with wild-type, with no net change in blood pharmacokinetics, consistent with transport in vivo by Pgp expressed at the capillary blood-brain barrier. Molecular imaging of the functional transport activity of ABC transporters in vivo with (99m)Tc-Tetrofosmin and related radiopharmaceuticals may enable non-invasive monitoring of chemotherapeutic and MDR gene therapy protocols.     

Azathioprine or methotrexate in the treatment of patients with steroid-dependent or steroid-resistant ulcerative colitis: results of an open-label study on efficacy and tolerability in inducing and maintaining remission

BACKGROUND: The role of azathioprine and methotrexate in inducing and maintaining remission in patients with ulcerative colitis is still controversial. AIM: To evaluate the efficacy and tolerability of these two drugs in a series of patients with steroid-dependent or steroid-resistant active ulcerative colitis. METHODS: Forty-two patients were treated with a daily dose of azathioprine (2 mg/kg) and, if intolerant or not responding, with methotrexate (12.5 mg/week intramuscularly), and their efficacy was established by clinical, endoscopic and histological examinations at 6 months. Patients achieving clinical remission continued with treatment and were followed up. RESULTS: Of the 42 patients on azathioprine, 10 experienced early side-effects requiring withdrawal from treatment, 22 (69%) achieved complete remission, six (19%) achieved improvement and four (12%) obtained no substantial benefit. Methotrexate, administered to eight patients intolerant to and two patients resistant to azathioprine, induced complete remission in six patients (60%) and improvement in four (40%). During follow-up, a larger number of patients on azathioprine relapsed in comparison with patients on methotrexate [16/28 (57%) vs. 2/10 (20%), respectively; P < 0.05]. Only minor side-effects were observed on both treatments. CONCLUSIONS: Azathioprine is effective in patients with steroid-dependent or steroid-resistant ulcerative colitis. Methotrexate seems to be a good alternative in patients intolerant to or not responding to azathioprine.     

Patterns of coronary compromise leading to bradyarrhythmias and hypotension in inferior myocardial infarction

BACKGROUND: Occlusion and reperfusion of the acutely occluded right coronary artery may result in abrupt bradycardia and hypotension, attributed to Bezold-Jarisch cardio-inhibitory reflexes arising from the ischemic left ventricle. Given that right ventricular infarction, a result of proximal right coronary artery occlusion, predisposes to bradycardia and hypotension, we hypothesized that proximal right coronary occlusions would be more likely to result in bradycardia-hypotension compared to more distal occlusions. METHODS: In 216 patients with acute inferior myocardial infarction undergoing primary angioplasty of the right coronary artery, we retrospectively analyzed the incidence of bradyarrhythmias and hypotension during occlusion and with reperfusion. RESULTS: Occlusion proximal to the right ventricular branches was identified in 151 (70%) of cases, with occlusions distal but compromising the left ventricular and atrioventricular nodal branches in 65 (30%) others. During occlusion, those with proximal occlusions were more likely to suffer hypotension (41 versus 15%, P=0.0002), advanced atrioventricular block (21 versus 3%, P=0.0008) and hypotension with bradycardia (25 versus 9%, P=0.01). Similarly, reperfusion of proximal occlusions more frequently resulted in abrupt hypotension (42 versus 19%, P=0.002), bradycardia (34 versus 14%, P=0.004) and hypotension with bradycardia (27 versus 12%, P=0.02). CONCLUSIONS: These data demonstrate that during right coronary artery occlusion and with reperfusion, bradycardia and hypotension develop more commonly in patients with proximal occlusions compared with those with distal occlusions. These findings suggest that reflexes arising from the ischemic right ventricle may play a role in bradyarrhythmias and hypotension.     

The origin of brain metastases in patients with an undiagnosed primary tumour

Summary Background. In patients presenting brain metastases as the first manifestation of a previously undiagnosed primary tumour (UDP) histopathological confirmation of the diagnosis can be obtained by either direct surgical sampling of the brain lesion or paraclinical search for an accessible primary tumour. The sequence of the diagnostic work-up and the timing of an eventual neurosurgical intervention are a matter of debate and are mainly influenced by the distribution of primary tumours in UDP patients. The aim of this study was to verify the hypothesis that the distribution of primary tumours differs between UDP patients and the rest of the patients with brain metastases (DP), and to propose a diagnostic work-up specifically tailored to the UDP population.Methods. Retrospective study on 342 patients admitted to the Lausanne University hospital between 1983 and 1998 with the diagnosis of cerebral metastases.Findings. UDP patients represented 36% of the whole group. Primary tumour location was significantly different between the two groups (p=0.001). Although the lung was the most frequent primary tumour location in both groups (UDP: 60%, DP: 43%), in UDP 14% only of the primaries were found outside of the lung and as much as 26% remained unknown despite thorough investigations.Conclusions. Our study confirmed the hypothesis that the relative frequency of primary tumours differs between DP and UDP patients. This difference therefore mandates a diagnostic strategy specifically tailored for UDP patients: if a radiological lung investigation clearly remains the best initial step in the work-up of these patients, extensive paraclinical investigations without a clear clinical suspicion should probably not be undertaken if this first survey fails to disclose the primary tumour as only 14% of the patients will actually benefit from it. In this situation, a neurosurgical procedure should probably be considered the most appropriate next step to be taken in order to provide a definitive diagnosis without unnecessary delays.