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71.
Visceral leishmaniasis: current status of control,diagnosis, and treatment,and a proposed research and development agenda 总被引:13,自引:0,他引:13
Guerin PJ Olliaro P Sundar S Boelaert M Croft SL Desjeux P Wasunna MK Bryceson AD 《The Lancet infectious diseases》2002,2(8):494-501
Visceral leishmaniasis is common in less developed countries, with an estimated 500000 new cases each year. Because of the diversity of epidemiological situations, no single diagnosis, treatment, or control will be suitable for all. Control measures through case finding, treatment, and vector control are seldom used, even where they could be useful. There is a place for a vaccine, and new imaginative approaches are needed. HIV co-infection is changing the epidemiology and presents problems for diagnosis and case management. Field diagnosis is difficult; simpler, less invasive tests are needed. Current treatments require long courses and parenteral administration, and most are expensive. Resistance is making the mainstay of treatment, agents based on pentavalent antimony, useless in northeastern India, where disease incidence is highest. Second-line drugs (pentamidine and amphotericin B) are limited by toxicity and availability, and newer formulations of amphotericin B are not affordable. The first effective oral drug, miltefosine, has been licensed in India, but the development of other drugs in clinical phases (paromomycin and sitamaquine) is slow. No novel compound is in the pipeline. Drug combinations must be developed to prevent drug resistance. Despite these urgent needs, research and development has been neglected, because a disease that mainly affects the poor ranks as a low priority in the private sector, and the public sector currently struggles to undertake the development of drugs and diagnostics in the absence of adequate funds and infrastructure. This article reviews the current situation and perspectives for diagnosis, treatment, and control of visceral leishmaniasis, and lists some priorities for research and development. 相似文献
72.
Outcome of anti-HBe positive chronic hepatitis B in alpha-interferon treated and untreated patients: a long term cohort study 总被引:27,自引:0,他引:27
Brunetto MR Oliveri F Coco B Leandro G Colombatto P Gorin JM Bonino F 《Journal of hepatology》2002,36(2):263-270
BACKGROUND/AIMS: We studied the influence of biochemical and virologic patterns and interferon on the outcome of anti-HBe positive chronic hepatitis B in 164 (103 treated) consecutive patients, followed-up prospectively for a mean of 6 years (21 months-12 years). METHODS: Histology, biochemical and virologic profiles were characterized by monthly monitoring during the first 12 months of follow-up. Thereafter patients underwent blood and clinical controls every 4 and 6 months, respectively. Cirrhosis at follow-up histology or end stage complications of cirrhosis served as end points for the analysis of factors influencing disease progression in patients with baseline chronic hepatitis or cirrhosis, respectively. RESULTS: Disease progression was associated with older age (P<0.001), absence of previous HBeAg history (P=0.017) and higher serum HBV-DNA levels (P=0.009) (more frequently observed in unremitting disease profile, P=0.012) at multivariate analysis. Fluctuations of IgM anti-HBc levels (associated with disease exacerbations, P=0.045) correlated with end stage complications in cirrhotics (P=0.011). Disease improved in 14.6 and 1.6% of treated and untreated patients, respectively (P=0.015): interferon slowed disease progression (P<0.001). CONCLUSIONS: The outcome of anti-HBe positive chronic hepatitis B is worsened by older age and persistent viral replication or hepatitis exacerbations in chronic hepatitis or in cirrhotic patients, respectively. Interferon reduces by 2.5-folds disease progression. 相似文献
73.
74.
Piero Marchetti Luca Benzi Maurizio Cerri Paolo Cecchetti Rosa Giannarelli Mauro Giannecchini Graziano Di Cianni Renza Cristofani Roberto Miccoli Alessandra Bertolotto Anna Zappella Renzo Navalesi 《Acta diabetologica》1988,25(1):55-62
Summary In this study we evaluated the relationships between plasma metformin levels, measured by reversed-phase high-performance
liquid chromatography, and serum lipid levels in 20 metformintreated, type II diabetic patients. Mean fasting plasma metformin
concentration was 490 ± 188 ng/ml. No correlation was found between daily dose of drug and lipid parameters. A significant
correlation emerged between circulating metformin concentration and serum triglycerides (r=−0.574, p<0.01), HDL-cholesterol
(r=0.583, p<0.01) and HDL2-cholesterol (r=0.670, p<0.05). Multiple linear regression analysis showed that the correlation between plasma metformin concentration
and serum triglycerides still remained significant after correction for other clinical and metabolic parameters. Total cholesterol
and HDL3-cholesterol were not correlated with metformin concentrations. These results demonstrate the clinical usefulness of measuring
plasma metforminc concentrations and indicate that some effects of metformin on lipid metabolism depend on the drug plasma
levels. 相似文献
75.
Piero Barbanti MD PhD Luisa Fofi MD Licia Grazzi MD Fabrizio Vernieri MD Cecilia Camarda MD Paola Torelli MD Sabina Cevoli MD PhD Antonio Russo MD PhD Francesco Bono MD Cinzia Finocchi MD Renata Rao MD Stefano Messina MD Roberto De Simone MD Nicola Vanacore MD PhD Stefano Bonassi PhD ERT IRON Study Group 《Headache》2021,61(6):936-950
76.
Piero Barbanti MD PhD Cinzia Aurilia MD Sabina Cevoli MD PhD Gabriella Egeo MD PhD Luisa Fofi MD Roberta Messina MD Antonio Salerno MD Paola Torelli MD Maria Albanese MD PhD Antonio Carnevale MD Francesco Bono MD Domenico D'Amico MD Massimo Filippi MD Claudia Altamura MD PhD Fabrizio Vernieri MD EARLY Study Group 《Headache》2021,61(9):1351-1363
77.
Piero Olliaro Luciano Lombardi Simona Frigerio Nicoletta Basilico Donatella Taramelli Diego Monti 《Ultrastructural pathology》2013,37(1):9-13
Hemozoin, the detoxification product of hemoglobin heme, piles up as electron-dense material in the food vacuole (FV) of intraerythrocytic malaria parasites (malaria pigment). In infected individuals, pigment is internalized by both circulating and resident phagocytes, thus modulating their functions. Synthetic beta-hematin, prepared in vitro from hematin (ferriprotoporphyrin IX hydroxide) in acidic condition, is spectroscopically identical to hemozoin. In this electron microscopy study, native and synthetic hemozoin also prove to be morphologically indistinguishable (large polygonal crystals with apparent transverse banding) and to undergo the same process when internalized by phagocytes (primarily a direct uptake of crystals, similar to what is described for asbestos fibers). On the contrary,whole parasites appear to follow a classical endocytic pathway. This suggests that there may be differences between the ingestion of free particles and whole parasites in terms of modulation of phagocytes' functions. 相似文献
78.
Daniele Recupero Lorenzo Daniele Caterina Marchiò Luca Molinaro Isabella Castellano Paola Cassoni Alberto Righi Filippo Montemurro Piero Sismondi Nicoletta Biglia Giuseppe Viale Mauro Risio Anna Sapino 《The Journal of pathology》2013,229(3):390-399
A subgroup of HER2‐overexpressing breast tumours co‐expresses p95 $^{{\rm{HER2}}}$ , a truncated HER2 receptor that retains a functional HER2 kinase domain but lacks the extracellular domain, thus impairing trastuzumab binding. We evaluated p95 $^{{\rm{HER2}}}$ expression in 99 frozen breast carcinoma samples by western blot analysis. The HER2‐positive cell line BT474 treated with pervanadate or pronase was used as a positive control for p95 $^{{\rm{HER2}}}$ expression. Immunohistochemistry was performed on parallel formalin‐fixed, paraffin‐embedded sections of the same case series using antibodies directed against either the intra‐ or extra‐cellular binding domain of HER2. In particular, biotinylated trastuzumab (BiotHER) was used to evaluate the binding capacity of the humanized antibody. To avoid a subjective evaluation of the score values and the percentage of immunostained cells, the slides were scanned and automatically analysed. The number of cases with HER2 overexpression (score 3+) and HER2 gene amplification was higher in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐positive samples than in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐negative group. Automated analysis confirmed a significantly higher percentage of 3+ scored cells in p95 $^{{\rm{HER2}}}$ ‐positive cases. Conversely, the percentage of 2+ scored cells was higher in p95 $^{{\rm{HER2}}}$ ‐negative cases. The status of the HER2 extracellular domain was then studied using flow cytometry on BT474 cells after pronase enzymatic digestion using trastuzumab and pertuzumab, while the presence of HER2‐HER3 dimers was studied using a proximity‐ligation assay. In vitro experiments showed that short‐term pronase digestion of BT474 cells produced two HER2 fragments (of 95 and 150 kDa, detectable in tissue specimens as well), increased the binding affinity of trastuzumab, reduced the rate of HER2–HER3 dimers, and did not interfere with pertuzumab‐binding capacity. In conclusion, the presence of p95 $^{{\rm{HER2}}}$ as detected by western blot analysis does not compromise the immunohistochemical detection of HER2. Our data suggest that a reduction of the receptor steric hindrance as induced by enzymatic shedding may facilitate the binding capacity of trastuzumab. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
79.
Deepanker Tewari Fabio Del Piero Stephen Cieply Willard Feria Helen Acland 《Journal of virological methods》2013
Equine herpesvirus-1 (EHV-1) strains with a single point mutation at the 2254 nucleotide position with a G2254 constitution within the DNA polymerase gene are associated strongly with equine myeloencephalopathies. Infections with non-neuropathogenic EHV-1 strains without the G2254 nucleotide but with an A2254 nucleotide are associated less frequently with equine neurologic disease. A retrospective study utilizing DNA extracted from formalin fixed paraffin embedded tissues was conducted with real time PCR and pyrosequencing, to determine the infecting EHV-1 strains. Infection with EHV-1 A2254 and or G2254 strain was detected with real time PCR, and was confirmed with a rapid pyrosequencing technique. Pyrosequencing was useful in at least 2 cases where real time PCR was equivocal in determining the infecting EHV-1 strain type. The strain with G2254 mutation was detected in 9.4% of 21 studied abortion cases, and in 86.6% of 15 neurologic cases. 相似文献
80.
Jakob K. Anninga Piero Picci Marta Fiocco Herman M. J. A. Kroon Daniel Vanel Marco Alberghini Hans Gelderblom Pancras C. W. Hogendoorn 《Virchows Archiv : an international journal of pathology》2013,462(1):109-120
Osteosarcomas of hands or feet are rare, and seemingly these cases differ in presentation and behavior compared to those in usual locations. The clinico-pathological presentation of patients with osteosarcomas of the hand or foot was studied and compared with published cases. Forty osteosarcomas were identified among 4,221 cases, representing 0.95 % of all osteosarcomas. Thirty of these were well documented. Mean age at diagnosis was 43 years (hands) and 36 years (feet) and male–female ratio was 1.2:1 and 2.0:1, respectively. In the hand, 62 % of the osteosarcomas presented in the metacarpals and 23 % in the phalanges, and only two cases occurred in the carpal bones. Distribution in the foot was tarsal bones 56 %, metatarsal bones 33 %, and phalanges 11 %.Of the cases in the hand 54 % were of high grade and of those in the foot 71 %. Survival of osteosarcomas of the hand or foot was 81 %. Only patients with high-grade osteosarcoma died of the disease. Histological grade was the only significant variable related to survival. High-grade osteosarcoma of the hand or feet should be treated similar to those in conventional sites. Osteosarcomas of hands or feet are rare and in a relative high proportion are of low grade. Survival in high-grade cases is comparable to that in conventional sites. 相似文献