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31.
Staphylococcal pathogenicity islands (SaPIs) carry superantigen and resistance genes and are extremely widespread in Staphylococcus aureus and in other Gram-positive bacteria. SaPIs represent a major source of intrageneric horizontal gene transfer and a stealth conduit for intergeneric gene transfer; they are phage satellites that exploit the life cycle of their temperate helper phages with elegant precision to enable their rapid replication and promiscuous spread. SaPIs also interfere with helper phage reproduction, blocking plaque formation, sharply reducing burst size and enhancing the survival of host cells following phage infection. Here, we show that SaPIs use several different strategies for phage interference, presumably the result of convergent evolution. One strategy, not described previously in the bacteriophage microcosm, involves a SaPI-encoded protein that directly and specifically interferes with phage DNA packaging by blocking the phage terminase small subunit. Another strategy involves interference with phage reproduction by diversion of the vast majority of virion proteins to the formation of SaPI-specific small infectious particles. Several SaPIs use both of these strategies, and at least one uses neither but possesses a third. Our studies illuminate a key feature of the evolutionary strategy of these mobile genetic elements, in addition to their carriage of important genes—interference with helper phage reproduction, which could ensure their transferability and long-term persistence.  相似文献   
32.
33.

Objective

An awake craniotomy facilitates radical excision of eloquent area gliomas and ensures neural integrity during the excision. The study describes our experience with 67 consecutive awake craniotomies for the excision of such tumours.

Methods

Sixty-seven patients with gliomas in or adjacent to eloquent areas were included in this study. The patient was awake during the procedure and intraoperative cortical and white matter stimulation was performed to safely maximize the extent of surgical resection.

Results

Of the 883 patients who underwent craniotomies for supratentorial intraaxial tumours during the study period, 84 were chosen for an awake craniotomy. Sixty-seven with a histological diagnosis of glioma were included in this study. There were 55 men and 12 women with a median age of 34.6 years. Forty-two (62.6%) patients had positive localization on cortical stimulation. In 6 (8.9%) patients white matter stimulation was positive, five of whom had responses at the end of a radical excision. In 3 patients who developed a neurological deficit during tumour removal, white matter stimulation was negative and cessation of the surgery did not result in neurological improvement. Sixteen patients (24.6%) had intraoperative neurological deficits at the time of wound closure, 9 (13.4%) of whom had persistent mild neurological deficits at discharge, while the remaining 7 improved to normal. At a mean follow-up of 40.8 months, only 4 (5.9%) of these 9 patients had persistent neurological deficits.

Conclusion

Awake craniotomy for excision of eloquent area gliomas enable accurate mapping of motor and language areas as well as continuous neurological monitoring during tumour removal. Furthermore, positive responses on white matter stimulation indicate close proximity of eloquent cortex and projection fibres. This should alert the surgeon to the possibility of postoperative deficits to change the surgical strategy. Thus the surgeon can resect tumour safely, with the knowledge that he has not damaged neurological function up to that point in time thus maximizing the tumour resection and minimizing neurological deficits.  相似文献   
34.
Apraxia of speech (AOS) is a rare, but well-defined motor speech disorder. It is characterized by irregular articulatory errors, attempts of self-correction and persistent prosodic abnormalities. Similar to aphasia, AOS is also localized to the dominant cerebral hemisphere. We report a case of Crossed Aphasia with AOS in a 48-year-old right-handed man due to an ischemic infarct in right cerebral hemisphere.  相似文献   
35.

Objective:

Poor documentation following lumbar puncture (LP) had always been a matter of concern. This study aimed to investigate the documentation pattern of neurology house officers, registrars (Regs), and specialist Regs following LP in a major teaching hospital.

Materials and Methods:

Total hundred patient records were examined in the light of a carefully designed proforma containing 15 important indicators of good-quality LP documentation.

Result:

Mean number of indicators overall documented by doctors was found to be 6.24 ± 3.0037. The mean number of indicators recorded by house officers was 5.11 ± 3.01 and Regs was 7.56 ± 3.28. A total of 33% LPs were performed without a documented consent. Only 36% performers documented the type and size of needle they used during the procedure. Only 46% documents revealed the strength and name of the local anesthetic used. Statistically significant difference between senior house officers and Regs in terms of numbers of indicators documented was noted.

Conclusion:

The documentation standard among neurology junior doctors remained poor.Key Words: Consent, documentation, knowledge, lumbar, neurology, puncture  相似文献   
36.

Introduction:

Our present observational study attempted to evaluate the clinical profiles, diagnosis, treatment and follow-up results of 51 pediatric neurocysticercosis patients over a mean duration of five years (from January 2006 to December 2010).

Materials and Methods:

Diagnosis was mainly based on clinical features, computed tomography (CT)/magnetic resonance imaging scan and exclusion of other causes. Patients with active, transitional cysts and seizure were treated with albendazole for 28 days, steroids and anticonvulsants.

Results:

A total of 38 patients completed this study. Mean age of the presentation was 8.47 ± 3.19 years 52.6% of the patients were female. Overall patients presented with generalized seizure in 55.3%, focal in 31.6%, headache ± vomiting in 63.2%, focal neurodeficit in 10.5% and combination of symptoms in 60.5% cases. Contrast CT brain showed a solitary lesion in 27 (71.1%) and multiple in the rest. At presentation lesions were transitional in 58.2%, inactive in 20% and mixed in 14.6%. After a mean of 2 years, seizure persisted in 9 (23.7%) and headache in 8 (21.1%) of whom six had normal electroencephalography (EEG) while one each showed focal slowing, generalized slowing and epileptiform discharges. During the follow-up, CT scan brain 44.7% lesions calcified, 31.6% disappeared, 10.5% regressed and the rest persisted.

Conclusion:

Solitary ring enhancing lesions (transitional stage) involving the parietal lobe was the commonest CT picture at presentation. Generalized tonic-clonic seizure was the most common type of seizure. Number of lesions, persistence of lesion, number of seizures, EEG abnormality at presentation were not found to be prognostically significant (P > 0.05).Key Words: Brain, epilepsy, lesion, neurocysticercosis, parenchyma, solitary  相似文献   
37.

Aims:

To evaluate clinical profile and short-term outcome of psychogenic non-epileptic seizures (PNES) in Indian adult population.

Setting and Design:

A prospective observational study, conducted at tertiary teaching institute at New Delhi.

Materials and Methods:

Sixty-three patients with confirmed PNES were enrolled. The diagnosis was based on witnessing the event during video-electroencephalography (Video-EEG) monitoring. A detailed clinical evaluation was done including evaluation for coexistent anxiety or depressive disorders. Patients were divided into two groups on the basis of excessive or paucity of movements during PNES attacks. Patients were followed-up to 12 months for their PNES frequency.

Statistical Analysis:

Means and standard deviations were calculated for continuous variables. Chi-square and Students t-test were used to compare categorical and continuous variables respectively.

Results:

The mean age at onset of PNES was 25.44 years; with F:M ratio of 9.5:1. Coexistent epilepsy was present in 13 (20.63%) cases. Twenty-two patients (44%) with only PNES (n = 50) had received antiepileptic drugs. Out of 63 patients of PNES 24 (38.1%) had predominant motor phenomenon, whereas 39 (61.9%) had limp attacks. The common features observed were pre-ictal headache, ictal eye closure, jaw clenching, resistant behavior, ictal weeping, ictal vocalization, and unresponsiveness during episodes. Comorbid anxiety and depressive disorders was seen in 62.3% and 90.16% patients, respectively. Short-term (6-12 months) outcome of 45 patients was good (seizure freedom in 46.66% and >50% improvement in 24.44% cases).

Conclusion:

PNES is common, but frequently misdiagnosed and treated as epileptic seizures. A high index of suspicion is required for an early diagnosis. Proper disclosure of diagnosis and management of the psychiatric comorbidities can improve their outcome.

Limitation:

Limited sample size and change in seizures frequency as the only parameter for the assessment of the outcome are the two major limitations of our study.  相似文献   
38.
Objectives Studies examining risk factors for preterm birth (PTB) such as psychosocial stress are often focused on women with a history of PTB; however, most preterm babies are born to women with no history of preterm birth. Our objective was to determine if the relationship between psychosocial stress and PTB is altered by parity. Non-Hispanic black (NHB) women have increased psychosocial stress and PTB; therefore, we further aimed to determine if race alters the relationship between psychosocial stress, parity, and PTB. Methods We performed a secondary analysis of the Healthy Pregnancy, Healthy Baby Study comparing pregnant women who were primiparous (first pregnancy), multiparous with history of preterm birth, or multiparous with history of term birth. Perceived stress, perceived racism, interpersonal support, John Henryism and self-efficacy were measured using validated instruments. Logistic regression was used to model the effect of psychosocial stress on PTB stratified by parity and race. Results The analysis entire cohort included 1606 subjects, 426 were primiparous, 268 had a history of presterm birth, and 912 had a history of term birth. In women with a history of term birth, higher self-efficacy was associated with lower odds of spontaneous PTB, and this association was amplified in NHB women. In women with a history of spontaneous PTB, John Henryism Active Coping was associated with lower odds of spontaneous PTB in the index pregnancy. Conclusions for Practice The relationship between psychosocial stress and PTB may be mediated by parity and race.  相似文献   
39.
This study investigated the hypothesis that coating eroded teeth with a resin-based dentin bonding agent gave protection from tooth wear. Nineteen adults with palatal tooth wear exposing dentin were recruited, following referral by their general dental practitioner. Alternate teeth were coated with the resin adhesive, while the uncoated teeth acted as controls. Accurate impressions of the eroded teeth, onto which were cemented machined stainless steel discs to act as reference areas, were scanned with a non-contacting laser profilometer at 3, 6, 12 and 24 months. The mean thickness of resin at baseline application was 0.15 mm and, from 0 to 6 months, the rate of wear of the control teeth was higher than those covered with Seal & Protect. There was a statistically significant difference in "wear" measured between resin covered and control teeth at three months. The Inter Class Correlations (repeated measurements) for the step heights obtained for the original and repeat impressions was excellent at 0.99. This study shows that coating eroded teeth with a resin-based adhesive has the potential to prevent further tooth wear.  相似文献   
40.
In light of the adverse reports of Bisphenol A (BPA) on reproduction and considering the pivotal role played by the steroid receptors (SRs) and their coregulators in male reproduction, it was of interest to decipher the influence that BPA may have on their expression pattern during critical ’windows‘ of development. Male rats were injected with 2.4 µg per pup per day of BPA from postnatal days (PND) 1–5 and controls received vehicle. During development, the testicular expression pattern of SRs (AR, ERβ and ERα), coactivators (SRC‐1, SRC‐2 and SRC‐3) and corepressors (NCoR and SMRT) in BPA‐exposed rats were compared. A significant decrease in the expression of SRs was seen in the BPA group. SRC‐1 showed a significant decrease, whereas SRC‐2 and SRC‐3 showed a significant increase in the protein expression whereas corepressor expression remained unaltered in the BPA‐exposed groups. Such impairments in the expression pattern can be a putative mechanism of adversities on fertility as a result of BPA exposure. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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