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41.
Spike activity in dorsal root ganglion (DRG) neurons depolarizes passive neighbors that share the same ganglion. We asked whether age or prior nerve injury affect this 'cross-depolarization' signal. Intracellular recordings made from excised DRGs in vitro revealed that the prevalence and duration of cross-depolarization were no greater in adult than in young rats, and that its amplitude was significantly smaller in adults. The amplitude of cross-depolarization was not affected by nerve injury. The decrease in membrane input resistance (R(in)) observed during cross-depolarization was less than that expected from equivalent depolarization alone. This affirms prior evidence that the neural process underlying cross-depolarization causes a net increase in R(in). 相似文献
42.
We have studied 50 Caucasoid children under 7 years of age with Haemophilus influenzae b disease. Half of the patients (Group A) had invasive disease shown by positive blood and/or spinal fluid culture. The other half (Group B) had noninvasive disease characterized by fever, nasopharyngitis, negative blood culture, and positive throat culture. Age, number of other siblings under 12 years old in the family, immune response, antibody production and genetic markers were compared in the two groups. Significant difference between the two groups was only seen in their genetic markers. HLA-B12 was present in 52% of Group A patients as opposed to 16% in Group B patients (P less than .01). HLA-Bw40 was present in 24% of group B patients and absent in all Group A patients (P less than .01). These findings would suggest that susceptibility and resistance towards developing invasive type b disease may be genetically determined. 相似文献
43.
Transcranial magnetic stimulation of the occipital pole interferes with verbal processing in blind subjects 总被引:6,自引:0,他引:6
Recent neuroimaging studies in blind persons show that the occipital cortex, including the primary visual cortex (V1), is active during language-related and verbal-memory tasks. No studies, however, have identified a causal link between early visual cortex activity and successful performance on such tasks. We show here that repetitive transcranial magnetic stimulation (rTMS) of the occipital pole reduces accuracy on a verb-generation task in blind subjects, but not in sighted controls. An analysis of error types revealed that the most common error produced by rTMS was semantic; phonological errors and interference with motor execution or articulation were rare. Thus, in blind persons, a transient 'virtual lesion' of the left occipital cortex interferes with high-level verbal processing 相似文献
44.
Dina Marek‐Yagel Yoav Bolkier Ortal Barel Amir Vardi David Mishali Uriel Katz Yishay Salem Shachar Abudi Omri Nayshool Nitzan Kol Annick Raas‐Rothschild Gideon Rechavi Yair Anikster Ben Pode‐Shakked 《American journal of medical genetics. Part A》2020,182(5):987-993
The genetic basis of congenital heart malformations associated with disruption of left–right (L–R) asymmetry is broad and heterogenous, with variants in over 25 genes implicated thus far. Of these, deleterious variants in the Growth/Differentiation Factor 1 (GDF1) gene have been shown to cause heterotaxy with varied complex heart malformations of left–right patterning, in 23 individuals reported to date, either in monoallelic or biallelic state. We report three unrelated individuals exhibiting right isomerism with congenital heart defects, each originating from a consanguineous kindred of Arab‐Muslim descent. Using whole exome sequencing, a shared novel homozygous truncating c.608G > A (p.W203*) variant in the GDF1 gene was revealed as the molecular basis of their disease. Subsequently, targeted sequencing of this variant showed full segregation with the disease in these families, with a total of over 15 reportedly affected individuals, enabling genetic counseling, prenatal diagnosis, and planning of future pregnancies. Our findings further confirm the association of biallelic GDF1 variants, heterotaxy and congenital heart defects of left–right patterning, and expand the previously described phenotypic spectrum and mutational profile. Moreover, we suggest targeted screening for the p.W203* variant in relevant clinical circumstances. 相似文献
45.
Raci Karayigit Alireza Naderi Firat Akca Carlos Janssen Gomes da Cruz Amir Sarshin Burak Caglar Yasli Gulfem Ersoz Mojtaba Kaviani 《Nutrients》2021,13(1)
Caffeine is widely consumed among elite athletes for its well-known ergogenic properties, and its ability to increase exercise performance. However, studies to date have predominantly focused on the anhydrous form of caffeine in male participants. The aim of the study was to investigate the effect of caffeinated coffee ingestion on lower-upper body muscular endurance, cognitive performance, and heart rate variability (HRV) in female athletes. A total of 17 participants (mean ± standard deviation (SD): age = 23 ± 2 years, body mass = 64 ± 4 kg, height = 168 ± 3 cm) in a randomized cross-over design completed three testing sessions, following the ingestion of 3 mg/kg/bm of caffeine (3COF), 6 mg/kg/bm of caffeine (6COF) provided from coffee or decaffeinated coffee (PLA) in 600 mL of hot water. The testing results included: (1) repetition number for muscular endurance performance; (2): reaction time and response accuracy for cognitive performance; (3): HRV parameters, such as standard deviation of normal-to-normal (NN) intervals (SDNN), standard deviation of successive differences (SDSD), root mean square of successive differences (RMSSD), total power (TP), the ratio of low- and high-frequency powers (LF/HF), high-frequency power (HF), normalized HF (HFnu), low-frequency power (LF), and normalized LF (LFnu). A one-way repeated measures ANOVA revealed that 3COF (p = 0.024) and 6COF (p = 0.036) improved lower body muscular endurance in the first set as well as cognitive performance (p = 0.025, p = 0.035 in the post-test, respectively) compared to PLA. However, no differences were detected between trials for upper body muscular endurance (p = 0.07). Lastly, all HRV parameters did not change between trials (p > 0.05). In conclusion, ingesting caffeinated coffee improved lower body muscular endurance and cognitive performance, while not adversely affecting cardiac autonomic function. 相似文献
46.
Munaza Fatima Santosh Kumar Mudassar Hussain Naveed Masood Memon Anum Vighio Muhammad Asif Syed Ambreen Chaudhry Zakir Hussain Zeeshan Iqbal Baig Mirza Amir Baig Rana Jawad Asghar Aamer Ikram Yousef Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures. 相似文献
47.
Shayan Taheri Farshid Davoodi Abbas Raisi Amir Zakian Asghar Rajabzadeh Mohammad Hassan Hablolvarid Abdolrahman khezri Hassan Ahmadvand 《Andrologia》2021,53(6):e14049
Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems. 相似文献
48.
Saurabh Kumar Bhushan Shah Ashok Johari Rashid Anjum Devansh Garg Rashmi Salhotra Asha Tyagi Amir Maroof Khan Anil Kumar Jain 《Indian Journal of Orthopaedics》2021,55(2):506
Covid-19 is a respiratory disease caused by coronavirus 2 (SARS-CoV-2) first identified in Wuhan, China (December 2019). The disease rapidly crossed the barrier of countries, continents and spread globally. Non-pharmaceutical measures such as social distancing, face mask, frequent hand washing and use of sanitizer remained the best available option to prevent the spread of disease. OPD, IPD admissions, elective O. Ts were curtailed. Orthopedic care was only limited to emergency and semi-urgent procedures like necrotizing fasciitis, open fracture, and compartment syndrome. These measures were taken to preserve infrastructure and manpower to manage covid-19 pandemic. The children were thought to have a low susceptibility to covid-19 as compared to an adult. Deferring the patient during pandemic has led to high orthopedic disease burden, morbidity and disease-related sequelae, hence elective care must be resumed with modified hospital infrastructure. Resumption of elective/emergent orthopedic care should be slow, phasic and strategic, much similar to unlocking. Cases must be stratified depending on covid status and severity. Dedicated O.Ts with neutral/negative pressure and HEPA filter for covid positive and suspected patients are to be used. All symptomatic and suspected patients should be investigated for covid-19 by RT-PCR, blood counts and CT scan. Regional anaesthesia should be preferred to General anaesthesia. Power drill/saw/burr/pulse lavage should be minimized to avoid aerosol generation. Postoperatively continuous surveillance and monitoring to be done for covid related symptoms. Medical institutes rapidly shifted to the online mode of education. Blended learning (virtual & physical) and imparting skills have to be continued in post covid phase with equitable distribution of teaching hours to students of different years. 相似文献
49.
Vikas S. Gupta Amir M. Khan Ashley H. Ebanks Pamela A. Lally Kevin P. Lally Matthew T. Harting 《Journal of pediatric surgery》2021,56(4):697-699
PurposeThere is a known association between Cornelia de Lange syndrome (CdLS) and congenital diaphragmatic hernia (CDH), with CDH being the cause of death in 5%–20% of CdLS cases. We aimed to identify and describe patients with CDLS and CDH. We hypothesized that CdLS would be associated with high-risk CDH and poor outcomes.MethodsCDH Study Group patients from 1995 to 2019 were included. Those with CdLS were reviewed retrospectively. Rates of repair and outcomes were compared between patients with and without CdLS.ResultsWe identified 9,251 CDH patients. Of those, 21 had confirmed CdLS. CdLS patients had a lower birth weight (2.2 ± 0.57 kg) than non-CdLS patients (2.9 ± 0.64 kg) (p < 0.001). 5-min Apgar scores were lower in CdLS patients (6, 4–7) than non-CdLS patients (7, 5–8) (p = 0.014). Only 33% of CdLS patients underwent diaphragmatic repair compared to 84.2% of non-CdLS patients (p < 0.001). Mortality was 76% for CdLS patients compared with 29% for non-CdLS patients (p < 0.001). Of the 7 CdLS patients who underwent repair, 5 survived to hospital discharge.ConclusionsInfants with CdLS and CDH have a poor prognosis. However, CdLS patients who undergo repair can survive to discharge; therefore, the concomitant diagnosis of CdLS and CDH is not necessarily a contraindication to repair. Early recognition of these anomalies can assist with counseling and prognostication.Type of studyRetrospective comparative studyLevel of evidenceIII 相似文献
50.
Elham Torkamaniha Mohammad Amir Amirkhani Mostafa Dahmardehei Paolo Rebulla Andrea Piccin Shamim Hortamani Maryam Heidari‐Kharaji Parvin Mansouri Amir Ali Hamidieh Mohammad Ali Nilforoushzadeh 《Wound repair and regeneration》2021,29(1):134-143
Epidermolysis bullosa (EB) is a rare genetic disorder characterized by the formation of blisters and wounds in skin and mucous membranes; it is classified into four types and has various methods of treatment. Management of previous wounds and prevention of formation of new lesions are the most important strategies in the course of therapy to improve patient's quality of life; lack of wound management can lead to further complications such as infection. The current study investigated the therapeutic effects of allogeneic platelet gel (prepared from umbilical cord blood) in a group of children diagnosed with dystrophic epidermolysis bullosa (DEB) eligible for surgical correction of pseudosyndactyly in the hand. The post‐surgical clinical outcome in this group was compared with the clinical outcomes of DEB patients receiving the standard treatment (paraffin gauze wound dressing and topical antibiotics) after corrective surgery. The current study results showed an increase in the rate of recovery and promotion of tissue granulation, complete wound healing, and a decrease in pain level and treatment period. The application of cord blood platelet gel topical dressing was not a conventional method of treatment in patients with DEB wounds and blisters. However, the current study results demonstrated that this gel dressing could effectively accelerate epithelialization and healing of the wounds and decrease patients' pain and post‐surgical recovery period, which altogether leads to improvements in patients' overall quality of life. 相似文献