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71.
Parkinson’s disease (PD) arises from the loss of dopaminergic neurons in the substantia nigra. 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) is well known to cause Parkinsonism in humans with neurotoxicity specific for dopaminergic neurons. The experience with MPTP supports the hypothesis that endogenous or xenobiotic neurotoxins are involved in the pathogenesis of PD in humans. In our study, 1-acetyl-6, 7-dihydroxy-1, 2, 3, 4-tetrahydro-isoquinoline (ADTIQ), a novel compound, was found in frozen human brain tissues. The formation of ADTIQ was demonstrated using dopamine and methylglyoxal under physiological conditions. Methylglyoxal is a by-product of glycolysis. ADTIQ and its precursors, dopamine and methylglyoxal, were detected in different regions of frozen human brains such as the substantia nigra, caudate nucleus, putamen, frontal cortex, and the cerebellum. A significant difference in ADTIQ levels between control and Parkinson’s patients was found; for instance, the ADTIQ level in putamen of PD patients was 0.76 ± 0.27 nmol/g compared to 0.10 ± 0.01 nmol/g in control. Our results might indicate that ADTIQ is possibly related to Parkinson’s disease.  相似文献   
72.
Some reports suggest cerebellar dysfunction as the basis of essential tremor (ET). Several drugs with the action of gamma-aminobutyric acid (GABA) are known to improve ET. Autopsy studies were performed on brains from nine former patients followed at the Movement Disorders Clinic Saskatchewan, Canada, and compared with five normal control brains. We aimed to measure the concentration of GABA B receptor 1 (GBR1) in the brains of patients who had had ET and to compare them to the GABA concentration in brains of controls. Western blot was used to determine the expression of GBR1 in cerebellar cortex tissue. We found that compared to the controls, the ET brains had three different patterns of GBR1 protein concentration--two with high, four comparable, and three with marginally low levels. There was no association between the age of onset, severity or duration of tremor, the response to alcohol or other drugs and GBR1 level. Thus, we conclude that our study does not support that GBR1 is involved in ET. Further studies are needed to verify these results.  相似文献   
73.
74.

Setting

Implementation study in private health facilities in an Indian metropolis.

Objectives

Improve Tuberculosis (TB) care by private practitioners (PPs).

Methods

PPs from a defined city area were imparted short training in TB care and linkages made with public facilities; subsequent practices were recorded.

Results

Of 364 presumptive TB patient records, 70 (19.3%) did not conform to its definition. Of the conforming, 174 (59.2%) had presumptive pulmonary TB (PTB), 53 (18%) presumptive extra-pulmonary (EPTB) and 67 (24%) had both. Of conforming presumptive PTB, most underwent Chest X-ray and sputum examination in private laboratories. Tissue based diagnostics were not advised for most presumptive EPTB patients. Of 101 cases diagnosed with TB, 82% were new, 23% known diabetic and 4.7% human immune deficiency virus (HIV) reactive out of 64 tested. Most were notified and initiated treatment within 15 days of diagnosis. One-fourth was prescribed standard treatment regimen and treatment was not directly observed for most. One third was initial defaulters or lost during treatment; 62% of PTB and 46% EPTB cases initiated on treatment in private were successfully treated. Of successfully treated PTB cases, 61% had undergone follow-up sputum examination.

Conclusion

Much intensified support mechanisms are needed to improve TB care in private sector.  相似文献   
75.
76.

Introduction

Anastomotic strictures at the gastrojejunal anastomosis have been reported to occur in 3–20% of patients following a Roux-en-Y gastric bypass (RYGB). Patients commonly present with dysphagia, vomiting and post-prandial pain. Clearly using the appropriate investigations to diagnose the potential complications have both clinical and economical benefits. The reported study compared whether Oesophagogastroduodenoscopy (OGD) or oral-contrast swallow should be employed in patient presenting with post-operative complications following RYGB.

Methods

A retrospective study was conducted on 112 patients between 2008 and 2012; at a level 4 bariatric surgery hospital. Patients who had ≥1 OGD to investigate a post-operative complication were included for analysis. Oral-contrast swallow radiology reports performed <28 days prior to an OGD were included for analysis. Patient demographics, OGD, oral-contrast swallow and additional interventions reports were collated from electronic records, pathology and radiology results.

Results

112 patients underwent 1 or more OGD. 75% (n = 67) of patients were diagnosed with a post-operative complication with the most common, 51% (n = 57) being a gastrojejunal anastomotic stricture. 82% (n = 47) of patients presented with dysphagia + - vomiting prior to the diagnosis of gastrojejunal anastomotic strictures. 96% (n = 55) of patients with gastrojejunal anastomotic strictures were successfully treated with balloon dilation. 48% (n = 54) of patients had an oral-contrast swallow as a first line investigation for post-operative symptoms prior to the OGD. 15% (n = 8) of oral-contrast swallow were reported with a significant pathology, with only 1 stricture identified. 70% (n = 38) of oral-contrast swallows reported as normal had a pathology identified at OGD, including 28 strictures.

Conclusion

We recommend that an OGD should be performed in patients presenting with symptoms consistent with a stricture following RYGB. The urgency of the OGD will be dictated by clinical correlation. The use of a water-soluble contrast swallow should be reserved for a suspected anastomotic leak.  相似文献   
77.
Absolute lymphocyte count (ALC) has been associated with overall survival (OS) and event-free survival, but we do not know if ALC is associated with minimal residual disease (MRD) at the end of induction (EOI) and whether it can be used as surrogate marker in resource limited settings. Immunological differences between MRD-positive and MRD-negative B ALL patients at the EOI are not known at present. This prospective study evaluated the association of ALC and peripheral blood lymphocyte subset percentage at the EOI with MRD. ALC was done at baseline, day 8, and day 15 and at EOI. Assessment for MRD and peripheral blood lymphocyte subset was done at EOI. In 2-year study duration, 197 B cell acute lymphoblastic leukemia (ALL) patients were recruited out of which 150 were analyzed. Peripheral lymphocyte subset percentage was available for 58 patients. We found that ALC at baseline, day 8, day 15, and EOI was not associated with MRD. Day 8 ALC was significantly higher in poor steroid responders (day 8 blasts?>?1?×?109 cells/l) (p?<?0.0001). At the EOI, CD4?CD8+ cell percentage in peripheral blood were significantly higher in MRD-positive patients than MRD-negative patients (p?=?0.01). Our study suggests that ALC at any point is not a surrogate marker for MRD. Immunologically MRD-positive and MRD-negative patients differ in CD4?CD8+ cells. The role of CD8+T and TCRαβCD3+T cells in eliminating residual leukemic cells need to be studied further by functional assays.  相似文献   
78.
OBJECTIVE: To determine the mechanism leading to striatal dopamine (DA) loss in dopa-responsive dystonia (DRD). BACKGROUND: Although mutations in the gene GCH1, coding for the tetrahydrobiopterin (BH4) biosynthetic enzyme guanosine triphosphate-cyclohydrolase I, have been identified in some patients with DRD, the actual status of brain BH4 (the cofactor for tyrosine hydroxylase [TH]) is unknown. METHODS: The authors sequenced GCH1 and measured levels of total biopterin (BP) and total neopterin (NP), TH, and dopa decarboxylase (DDC) proteins, and the DA and vesicular monoamine transporters (DAT, VMAT2) in autopsied brain of two patients with typical DRD. RESULTS: Patient 1 had two GCH1 mutations but Patient 2 had no mutation in the coding region of this gene. Striatal BP levels were markedly reduced (<20% of control subjects) in both patients and were also low in two conditions characterized by degeneration of nigrostriatal DA neurons (PD and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treated primate), whereas brain NP concentrations were selectively decreased (<45%) in the DRD patients. In the putamen, both DRD patients had severely reduced (<3%) TH protein levels but had normal concentrations of DDC protein, DAT, and VMAT2. CONCLUSIONS: The data suggest that 1) brain BH4 is decreased substantially in dopa-responsive dystonia, 2) dopa-responsive dystonia can be distinguished from degenerative nigrostriatal dopamine deficiency disorders by the presence of reduced brain neopterin, and 3) the striatal dopamine reduction in dopa-responsive dystonia is caused by decreased TH activity due to low cofactor concentration and to actual loss of TH protein. This reduction of TH protein, which might be explained by reduced enzyme stability/expression consequent to congenital BH4 deficiency, can be expected to limit the efficacy of acute BH4 administration on dopamine biosynthesis in dopa-responsive dystonia.  相似文献   
79.
Neurodegeneration is a complex neurological phenomenon characterized by disturbed coherence in neuronal efflux. Progressive neuronal loss and brain damage due to various age-related pathological hallmarks perturb the behavioral balance and quality of life. Sirtuins have been widely investigated for their neuroprotective role, with SIRT1 being the most contemplated member of the family. SIRT1 exhibits significant capabilities to enhance neurogenesis and cellular lifespan by regulating various pathways, which makes it an exciting therapeutic target to inhibit neurodegenerative disease progression. SIRT1 mediated neuronal fortification involves modulation of molecular co-factors and biochemical pathways responsible for the induction and sustenance of pro-inflammatory and pro-oxidative environment in the cellular milieu. In this review, we present the major role played by SIRT1 in maintaining cellular strength through the regulation of genomic stability, neuronal growth, energy metabolism, oxidative stress, inhibiting mechanisms and anti-inflammatory responses. The therapeutic significance of SIRT1 has been put into perspective through a comprehensive discussion about its ameliorating potential against neurodegenerative stimuli in a variety of diseases that characteristically impair cognition, memory and motor coordination. This review enhances the acquaintance concerned with the neuroprotective potential of SIRT1 and thus promotes the development of novel SIRT1 regulating therapeutic agents and strategies.  相似文献   
80.
Parkinson’s disease (PD) is the second most familiar, progressive and movement-related neurodegenerative disorder after Alzheimer disease. This study aimed to decipher the role of autophagy in cypermethrin-induced Parkinsonism, an animal model of PD. Indicators of autophagy [expression of beclin 1, autophagy-related protein 12 (Atg 12), unc-51 like autophagy activating kinase 1 (Ulk 1), p62 and lysosome-associated membrane protein 2 (LAMP 2) and conversion of microtubule-associated protein 1A/1B-light chain 3 (LC3) I to II], signalling cascade [phosphorylated (p) 5′ adenosine monophosphate-activated protein kinase (p-AMPK), sirtuin 1 (Sirt 1), phosphorylated-mammalian target of rapamycin (p-mTOR), tuberous sclerosis complex 2 (TSC 2), p317Ulk 1 and p757Ulk 1 levels] and lysosome morphology were assessed in control and cypermethrin-treated rat model of PD. Autophagy markers were also measured in cypermethrin-treated neuroblastoma cells in the presence of 3-methyl adenine, a phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) class III inhibitor; vinblastine, an autophagosome elongation inhibitor; bafilomycin A1, an autophagolysosome and lysosome fusion/abnormal acidification inhibitor or torin 1, a mechanistic target of rapamycin inhibitor. Cypermethrin reduced LAMP 2 and increased p-AMPK and Sirt 1 without causing any change in other signalling proteins. 3-Methyl adenine did not change LC3 conversion; vinblastine and bafilomycin A1 decreased LAMP 2 expression in controls. While cypermethrin increased LC3 conversion in the presence of 3-methyl adenine, LAMP 2 reduction was more pronounced in vinblastine and bafilomycin A1-treated cells. Torin 1 normalized the expression of LAMP 2 without any change in other autophagy markers. Results demonstrate that albeit cypermethrin activates autophagosome formation, it reduces LAMP 2 expression and lysosome quality leading to autophagy inhibition.  相似文献   
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