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1.
Lasers in Medical Science - Melasma is a chronic, dark brown–pigmented patches and macules commonly on the face. Many treatment modalities for melasma have been used as hydroquinone, laser...  相似文献   
2.
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease.  相似文献   
3.
We have tested whether the ability of synapses to compete for occupancy of endplates during neuromuscular synapse elimination is affected by differences in the spinal position or in the activity level of the parent motor neuron. To test the role of spinal position, the relative sizes of motor units for motor neurons from middle and extreme (rostral/caudal) positions in the rabbit soleus motor pool were determined at 3 postnatal ages: 4-5 d ("early" ages, when the soleus is heavily polyinnervated), 8-9 d ("intermediate"), and 11-15 d ("late," when the soleus has just reached singly innervated state). Average motor unit sizes from extreme ventral roots were similar to those from middle ventral roots in early-aged soleus muscles but were significantly smaller (by 18-27%) for both intermediate and late muscles. Thus, motor neurons from extreme positions evidently compete less effectively for retention of synapses than those from middle positions. To test the role of differential activity, inactive and active synapses were pitted directly against one another by implanting Silastic plugs laden with tetrodotoxin (TTX) into one of the spinal nerves containing a minority of the soleus motor axons. Differential activity was maintained during a period of extensive synapse loss, from the time of the implant at day 4 or 5 until the intermediate age (day 8-9). Motor unit twitch tensions were subsequently measured to determine the relative number of synapses retained by individual active and inactive motor neurons. The inactivated motor units were on average significantly larger (by more than 50%) than the corresponding group from normal and control-implanted animals. The abnormally large size of inactivated motor units persisted in animals allowed to recover from the TTX block and examined after multiple innervation had disappeared. Hence, the effect of the TTX block cannot be attributed to a simple slowing of synapse elimination specifically among the inactive motor neurons. We conclude that complete presynaptic inactivity improves the chances of survival relative to that for normal activity during synapse elimination in the neonatal rabbit soleus muscle. This difference in competitive ability may contribute to the development of an important characteristic of adult muscles, the correlation between motor unit size and recruitment threshold.  相似文献   
4.
We report on a 2.5-month-old boy with hypertelorism, hypertrichosis, anteverted nostrils, malformed ears, thin lips, downturned corners of the mouth, micrognathia, short neck, cryptorchidism, and bilateral simian creases without limb anomalies. Cytogenetic studies showed a duplication 3q → qter 46,XY,der(6),t(3;6)(q21;p25)pat. The absence of limb anomalies is noteworthy; all 12 previously reported patients with the same duplication had limb anomalies. The uniqueness of this report provokes speculations regarding limb morphogenesis in embryos with chromosome anomalies. The concepts of chronogenetics, heterochrony, and developmental field defects appear relevant to yet another set of patients with chromosome anomalies.  相似文献   
5.
Aim of the workThe aim of the present study was to measure the level of the chemokine CXC ligand 13 protein (CXCL13) in the plasma and unstimulated saliva of rheumatoid arthritis (RA) patients in order to find out its role in the disease activity and its relation to secondary Sjögren’s syndrome (sSS).Patients and methodsThe study was conducted on thirty rheumatoid arthritis patients attending the Outpatient Clinic of Rheumatology and Rehabilitation department of Ain shams University Hospitals. The patients’ group had been classified into group (1) which included fifteen RA patients associated with sSS diagnosed according to the American–European Consensus Group Classification Criteria and group (2) which included fifteen RA patients not associated with sSS. Ten healthy subjects were included as a control group. Patients were subjected to full history taking, clinical examination, and laboratory detection of CXCL13 level in the plasma and saliva of patients as well as the control groups using ELISA technique. Assessment of disease activity in RA patients was done using the disease activity score (DAS28).ResultsPlasma levels of CXCL13 were significantly higher in RA patients than control group (p < 0.001). Plasma levels of CXCL13 were significantly correlated with the RA disease activity (r = 0.677, p < 0.001) and disease duration (r = 0.406, p < 0.05), while the salivary levels were higher in those with sSS and correlated with sSS disease duration (r = 0.536, p < 0.05). A highly significant correlation was found between salivary CXCL13 and severity of sSS (r = 0.816, p < 0.001). Salivary levels of CXCL13 above 110 pg/ml may diagnose sSS with sensitivity 80% and specificity 84%.ConclusionThe results of this preliminary study point out the importance of CXCL13 as a marker for RA disease activity, its role in diagnosing sSS, and estimation of sSS severity.  相似文献   
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8.
HSV‐1 epidemiology in the Middle East and North Africa (MENA) remains poorly understood. Our study aimed to measure HSV‐1 antibody prevalence (seroprevalence) and its age‐distribution among select MENA populations residing in Qatar. Sera were collected from male blood donors attending Hamad Medical Corporation 2013‐2015. A total of 2,077 sera were tested for anti‐HSV‐1 antibodies using HerpeSelect® 1 ELISA IgG kits (Focus Diagnostics, Cypress, CA). Robust Poisson regression was conducted to estimate adjusted infection prevalence ratios. Country‐specific HSV‐1 seroprevalence was estimated for 10 national populations: 97.5% among Egyptians, 92.6% among Yemenis, 90.7% among Sudanese, 88.5% among Syrians, 86.5% among Jordanians, 82.3% among Qataris, 81.4% among Iranians, 81.4% among Lebanese, 80.5% among Palestinians, and 77.0% among Pakistanis. Age‐specific HSV‐1 seroprevalence was estimated for Egypt, the Fertile Crescent (Iraq, Jordan, Lebanon, Palestine, and Syria), and Qatar. Seroprevalence increased with age among Fertile Crescent and Qatari nationals. Seroprevalence increased from 70.0% among those aged ≤ 24 years up to 98.0% among those aged ≥55 years among Fertile Crescent nationals. Seroprevalence was consistently above 90% for all ages among Egyptians. HSV‐1 seroprevalence is high in MENA, though with some variation across countries. The seroprevalence appears to have declined among current young age cohorts compared to its levels a few decades ago.  相似文献   
9.

Aim of the work

To evaluate the efficacy of intra-articular steroid injection of the shoulder joint with exercises in the management of patients with adhesive capsulitis and to compare glenohumeral (GH) versus subacromial subdeltoid (SASD) ultrasound-guided approaches.

Patients and methods

Forty patients with adhesive capsulitis were randomly divided into 2 groups according to injection approach. Patients received ultrasound-guided intra-articular injection methylprednisolone acetate (40?mg) and 1?ml 2% lidocaine followed by exercise for 12?weeks. Visual analog scale (VAS) for pain, the shoulder pain and disability index (SPADI) and active range of motion (ROM) were assessed before and 12?weeks post-injection.

Results

The mean age of the patients was 47.3?±?8.7?years with 12 females and 8 males in each group. After injection, there was a significant improvement of pain (VAS) and SPADI in both groups (p?<?0.001). Before injection, SASD bursitis was present in 18 (45%), GH joint effusion in 14 (35%), rotator cuff tendinopathy in 6 (15%), bursitis with effusion in 1 (2.5%) and with supraspinatus tendon calcification in another (2.5%). Both groups significantly equally improved regarding to ROM compared to before injection. Post-injection, the SPADI significantly improved in the SASD group compared to GH; with remarkable improvement in the joint extension, internal and external rotation (p?<?0.001).

Conclusion

Intrarticular steroid injection of the shoulder joint followed by exercises in patients with adhesive capsulitis decreases pain, improves function and ROM with a more favorable response by the GH approach. Ultrasound-guided injection is an accurate, easy and cost-effective approach.  相似文献   
10.

Objective

We evaluated the effectiveness of long acting penicillin (LAP) as a 2-weekly regimen in winter and a 3-weekly regimen in summer for prevention of streptococcal colonization and also studied the common complaints of patients during the period of compliance for LAP administration. We also attempted to determine the incidence of relapses or recurrence of rheumatic fever (RF) after the onset of first episode of RF.

Patients & methods

210 rheumatic patients with good compliance to LAP (for at least one year) were included in the study. Demographic, clinical information, patients'' complaints and echocardiographic data of rheumatic patients were collected both retrospectively and prospectively. Anti-streptolysin O titre (ASOT) and throat swab culture were done at the end of the study (on Day 14 in the 2-weekly regimen and on Day 21 in the 3-weekly regimen).

Results

The age of onset of rheumatic fever was mostly between 5 and 15 years and the youngest patient was 2 years old. Subclinical carditis (SCC) was present in 79 (37%) of all the patients in the study population. Only 7 patients (3.3%) had a relapse within 2 years of the acute episode of RF. At the end of the study, ASOT was found to be high only in 11 patients (5.2%) and throat swab cultures were found negative in all patients

Conclusion

LAP regimen is fairly effective in eradicating streptococcal colonization. The incidence of relapse of RF within 2 years of the acute episode of RF is relatively low.  相似文献   
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