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71.
72.
Fernand Mac-Moune Lai Kar Neng Lai Edmund K. Li Jao Yiu Sung John S. L. Tam 《Virchows Archiv : an international journal of pathology》1989,415(2):181-186
Summary Immunotactoid glomerulopathy is a distinct clinico-pathological entity which has recently been defined. The term immunotactoid refers to highly organized immune depositions appearing as rod-like microtubular structures in ultrastructural examination. We describe a patient with mixed connective tissue disease who demonstrates characteristic features of immunotactoid glomerulopathy. The diagnosis was made after excluding amyloidosis, cryoglobulinaemia and lupus nephritis. In addition to immunotactoid microtubules, ultrastructural examination also demonstrated presence of fingerprint depositions which were intimately mixed with immunotactoid structures. Fingerprint deposits have been described in lupus nephritis and cryoglobulin-related nephropathy, but rarely in other glomerulonephritis. These unique findings in our patient may suggest a previously unsuspected relationship between the syndrome of immunotactoid glomerulopathy and systemic lupus erythematosus. 相似文献
73.
74.
Amyloid beta peptide induces tau phosphorylation and loss of cholinergic neurons in rat primary septal cultures 总被引:6,自引:0,他引:6
The neuropathological features associated with Alzheimer's disease (AD) brain include the presence of extracellular neuritic plaques composed of amyloid beta protein (Abeta), intracellular neurofibrillary tangles containing phosphorylated tau protein and the loss of basal forebrain cholinergic neurons which innervate regions such as the hippocampus and the cortex. Studies of the pathological changes that characterize AD and several other lines of evidence indicate that Abeta accumulation in vivo may initiate phosphorylation of tau protein, which by disrupting neuronal network may trigger the process of neurodegeneration observed in AD brains. However, the underlying cause of degeneration of the basal forebrain cholinergic neurons and their association, if any, to Abeta peptides or phosphorylated tau remains mostly unknown. In the present study, using rat primary septal cultures, we have shown that aggregated Abeta peptides, in a time (18-96 h)- and concentration (0.7-60 microM)-dependent manner, induce toxicity and decrease choline acetyltransferase enzyme activity in cultured neurons. Using immunocytochemistry and immunoblotting, we have also demonstrated that Abeta treatment can significantly increase the phosphorylation of tau protein in septal cultures. At the cellular level, hyperphosphorylated tau is mostly apparent in the somatodendritic compartment of the neurons. Abeta peptide (10 microM), in addition to tau phosphorylation, also activates mitogen-activated protein kinase and glycogen synthase kinase-3beta, the two kinases which are known to be involved in the formation of hyperphosphorylated tau in the AD brain. Exposure to specific inhibitors of the mitogen-activated protein kinase (i.e. PD98059) or glycogen synthase kinase-3beta (i.e. LiCl) attenuated the hyperphosphorylation of the tau protein in cultured neurons.Given the evidence that tau phosphorylation can induce cell loss by disrupting neuronal cytoskeleton, it is likely that aggregated Abeta peptide triggers degeneration of septal neurons, including those expressing the cholinergic phenotype, by phosphorylation of the tau protein activated by mitogen-activated protein kinase and glycogen synthase kinase-3beta. These results, taken together, suggest that cultured septal cholinergic neurons are vulnerable to Abeta-mediated toxicity and tau phosphorylation may play an important role in Abeta-induced neurodegeneration. 相似文献
75.
Saha S Mazumdar T Anam K Ravindran R Bairagi B Saha B Goswami R Pramanik N Guha SK Kar S Banerjee D Ali N 《Journal of clinical microbiology》2005,43(3):1269-1277
Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), caused by Leishmania donovani, is difficult, as the dermal lesions are of several types and resemble those caused by other skin diseases, especially leprosy. Since the disease generally appears very late after the clinical cure of kala-azar in India, it is also difficult to correlate PKDL with a previous exposure to L. donovani. Very few attempts have been made so far to diagnose PKDL serologically, and the diagnostic methods vary in their sensitivities and specificities. Diagnosis of PKDL through sophisticated PCR methods, although highly sensitive, has limited practical use. We have developed a serodiagnostic method using an enzyme-linked immunosorbent assay to detect specific immunoglobulin (Ig) isotypes and IgG subclass antibodies in the sera of Indian PKDL patients. Our assay, which uses L. donovani promastigote membrane antigens, was 100% sensitive for the detection of IgG and 96.7% specific for the detection of IgG and IgG1. Optical density values for individual patients, however, demonstrated wide variations. Western blot analysis based on IgG reactivity could differentiate patients with PKDL from control subjects, which included patients with leprosy, patients from areas where kala-azar is endemic, and healthy subjects, by the detection of polypeptides of 67, 72, and 120 kDa. The recognition patterns of the majority of serum samples from patients with PKDL were also distinct from those of the serum samples from patients with visceral leishmaniasis (VL), at least for a 31-kDa polypeptide. To further differentiate patients with PKDL from those with active and cured VL, we analyzed the specific titers of the Ig isotypes and IgG subclasses. High levels of IgG, IgG1, IgG2, and IgG3 antibodies significantly differentiated patients with PKDL from patients cured of VL. The absence of antileishmanial IgE and IgG4 in patients with PKDL differentiated these patients from those with active VL. These results imply intrinsic differences in the antibodies generated in the sera from patients with PKDL and VL. 相似文献
76.
1. Extracellular single neuron activity was recorded in the lateral hypothalamic area (LHA) of awake, behaving monkeys, with particular regard to the feeding-related functional characteristics of glucose-sensitive (GS) versus glucose-insensitive (GIS) neurons. Firing rate changes were recorded by means of carbon fiber, multibarreled glass microelectrodes during 1) microelectrophoretic application of various chemicals, 2) gustatory and olfactory stimulation, and 3) a high fixed-ratio schedule (FR) bar press feeding task. 2. In 336 neurons examined, 91 (27%) were suppressed by electrophoretically administered glucose, and so they were designated as GS cells. The 245 neurons (73%) in which the firing rates did not change during glucose applications were pronounced GIS. The 179 GS and GIS cells tested exhibited different responses to the catecholamines (CAs), noradrenaline (NA) and dopamine (DA), both of which are intimately involved in the control of feeding. More GS neurons responded to NA than did GIS cells; the predominant effect of both CAs on GS neurons was inhibition. 3. The taste responsiveness of 111 LHA neurons was examined. Fifty-seven cells (52%) showed responses to gustatory stimulation. Of 50 GS neurons tested, 33 (66%) exhibited firing rate changes to tastes. On the contrary, only 24 (39%) of the 61 GIS neurons examined responded to gustatory stimuli. Activity changes of GS neurons commonly occurred to two or more tastants, in distinction to the relative gustatory specificity shown by GIS cells. 4. Two hundred fifty-six (84%) of the 303 neurons tested responded during one or more phases of the bar press feeding task. Most activity changes occurred during the bar press (BP) and reward (RW) periods, however numerous phasic responses to cue light (CL) and cue tone (CT) were also observed. A higher proportion of the GS neurons showed task-related activity changes than did the GIS cells (77, 95% and 179, 81%, respectively). GS neurons responded more during the BP phase and to the food reward; GIS cells were more responsive during the CL that enabled acquisition and the CT that signaled reward. Thus GS neurons were responsive during the acquisition and consumption of reward, whereas GIS cells responded to external cues signaling both of these events. The gustatory neurons displayed specific task-related activity changes only in the CL (GIS cells) and BP phases (GS neurons), that is, in phases most intimately involved in sensory-motor integration. 5. Two-thirds of the 30 GS neurons tested were responsive to both gustatory and olfactory stimulation as opposed to only one-third of GIS cells.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
77.
Abdullah Saleh AlQattan MBBS Weaam Zohier Ghulam MBBS Najla Aldaoud MBBS Lama Algheryafi MBBS Nadia Aleisa MBBS Fozan A. Aldulaijan MBBS 《The breast journal》2021,27(3):258-263
Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease. 相似文献
78.
Xuejin Ma ME Xiaoxi Chen MD Guoyuan Jiang MBBS Lin Jiang MD Tingchao Li MBBS Ling Wei MBBS Shiguang Li MD 《The breast journal》2021,27(12):890-894
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type. 相似文献
79.
Hussan Zeb RN BSN MSPH Ahtisham Younas RN BSN MN Israr Ahmed RN BSN Anwar Ali MBBS FCPS MRCP 《Health & social care in the community》2021,29(5):e174-e183
Self-care enables patients in improving quality of life and reducing hospital admissions. Research explored the experiences of patients about breathlessness, sleep problems and complication management in chronic obstructive pulmonary disease (COPD). However, the self-care experiences and the role of the family in self-care are underexplored. This study aimed to understand the self-care experiences of patients with COPD and explore the role of the family in self-care. An interpretive phenomenological inquiry was used, and 13 patients were interviewed in 2019 from two hospitals in Pakistan. The inclusion criteria were patients above 30 years of age at any stage of COPD, who received a confirmed diagnosis of COPD and were receiving the treatment, and engaged in self-care at their homes or communities. The interviews lasted for 35–60 min. Ricoeur's interpretation theory was used for data analysis comprising steps explanation, naive understanding and in-depth understanding. Self-care emerged as a complex individual and familial endeavour affected by personal, social and economic factors. Poverty was one of the core determinants of self-care. Patients emphasised the spiritual, cultural and traditional approaches to self-care. Future research is warranted to develop better understanding of spiritual and cultural self-care and how these dimensions of self-care affect patients’ self-care behaviours. 相似文献
80.
Caitlin H. Douglass BHSc Karen Block PhD Danielle Horyniak PhD Margaret E. Hellard MBBS FRACP PhD FAFPHM Megan S. C. Lim PhD 《Health & social care in the community》2021,29(6):e308-e317
Young people from migrant and ethnic minority backgrounds are recognised as emerging priority populations for reducing alcohol and other drug (AOD)-related harms in Australia. Limited research has investigated how service providers address AOD challenges in migrant communities. In this qualitative study, we interviewed 15 service providers from AOD, migrant support, community and other health services in a diverse region of Melbourne. Interviews explored the challenges that service providers faced and the strategies they implemented to engage with young migrants in relation to AOD use. Thematic analysis was used to generate four themes: stigma as a barrier to service delivery, intergenerational differences between young people and parents, the need for outreach and establishing trust and understanding over time. Service providers believed that stigma prevented many young people from migrant backgrounds having open conversations about their AOD use with family members and professionals. Participants perceived that some parents had less AOD-related knowledge and lower English language proficiency than their children creating challenges for effective communication. Service providers recognised the importance of engaging with young people in settings where they felt comfortable rather than expecting them to approach their service. Participants also acknowledged the need to invest time in establishing trust and understanding with young migrants so they could facilitate conversations about AOD use as relationships evolved. Although service providers had a strong understanding of young people's needs, they found it challenging to build relationships in the context of funding and time constraints. Our results indicate the need for long-term funding and timelines that enable service providers to build strong relationships with young migrants, their families and their broader cultural communities to facilitate access to AOD support. 相似文献