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1.
Sci Rep ; 13(1): 14180, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648712

RESUMO

In this paper, novel compact high-efficiency multi-band rectifiers that supply positive and negative output voltages are demonstrated for energy harvesting applications. The proposed voltage doubler circuits are used as real DC voltage supplies of radio frequency mm-wave CMOS receivers. Operating multi-band rectifiers have a complicated structure that required more resonance networks to force the rectifier to work in multi-band. Novel series and parallel resonance networks are implemented to force the rectifier to operate in dual-band at frequencies of 850 and 1400 MHz. The proposed resonance network eliminates the Schottky diode impedance variation as the input power or frequency changes and supports the impedance matching and minimizes the insertion loss. A novel high-quality sine-shape micro-strip inductor that obtains a quality factor above 65 over the frequency band from 200 to 1400 MHz and inductance equal to 14 ± 2 nH is designed to improve efficiency and enhance performance at low power levels. The first suggested RF voltage doubler rectifier with series resonance feedback between the input and cathode of the diode and parallel resonance operates at two frequency bands of 850 and 1400 MHz and obtains a peak conversion efficiency of 59%, a saturated output DC voltage is 2.5 V, and the conversion efficiency is 40% at RF-input-power of - 10 dBm. This voltage doubler achieves the required DC supply parameter (1.1 V and 450 uA) for biasing the mm-wave receiver at an RF input power of 0 dBm. Otherwise, the second suggested negative voltage rectifier has a maximum simulated conversion efficiency of 65%, saturated negative DC-voltage is - 3.5 V, and the conversion efficiency is 45% at an RF input power of - 10 dBm. The negative voltage rectifier obtains DC supply parameters (- 0.5 V and no current condition used for a gate bias) at - 10 dBm input power.

2.
Arab J Urol ; 21(3): 142-149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521452

RESUMO

Background: We lack tools to predict treatment and survival outcomes in patients receiving additional BCG therapy as a bladder-preserving therapy in high grade/T1, Tis NMIBC patients who showed persistent/recurrent tumors at three-month follow-up. Objectives: To assess the predictors of additional BCG response in patients who experienced persistent/recurrent tumors at three-month follow-up after BCG induction. Patients and methods: We retrospectively analyzed database for NMIBC. Between 2000 and 2019, 231 patients with high-grade T1/Tis NMIBC showed persistent/recurrent tumors at 3-month after BCG-induction, refused or were unfit to radical cystectomy (RC) and were offered additional intravesical BCG as bladder-preserving treatment. Predictors of the outcome after additional BCG were studied using univariate and multivariate logistic regression analysis. Kaplan Meier curve was utilized to estimate the recurrence-free survival (RFS) and progression-free survival (PFS). COX regression analysis was performed to identify independent predictors or RFS and PFS. Results: During a median (range) of 148 (24-224) months, poor response to additional BCG (tumor recurrence and/or progression) was noted in 112 (48.5%) patients. On multivariate logistic regression analysis, 3-month tumor features (persistent T stage, persistent grade and persistent/new CIS) significantly predicted poor response to additional BCG (OR: 3.4, 95%CI: 1.3-10.8, p = 0.021, OR: 2.1, 95%CI: 1.1-4.1, p = 0.02 and OR: 16.6, 95%CI: 4.5-109, p=<0.001, respectively). The mean RFS was 26 (9-152) months with identified 3-month tumor features (persistent T stage and persistent/new CIS) as independent predictors of RFS (HR = 11.5, 95%CI = 2.7-48.3, p = 0.001 and HR = 2.5, 95%CI = 1.5-4.1, p=<0.001, respectively) on multivariate COX regression analysis. In addition, 3-month tumor features (persistent/new CIS, non-papillary shape and bladder neck involvement) were identified to significantly predict PFS (HR = 6.2, 95%CI = 3.4-11.5, p=<0.001 and HR = 2.3, 95%CI = 1.3-4.3 p = 0.001 and HR = 2.1, 95%CI = 1.2-3.8, p=<0.005, respectively). Conclusions: Three-month tumor features could be utilized as a tool to predict treatment outcomes and survival benefits when additional intravesical BCG is utilized as a bladder-preserving treatment in patients with recurrent/persistent tumors at three-month follow-up.

3.
Ann Med Surg (Lond) ; 80: 104253, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36045837

RESUMO

Introduction and importance: Hereditary Folate Malabsorption (HFM) is an extremely rare autosomal recessive disorder with in the existence of only 30 families world-wide. It presents with hematological, gastrointestinal, and neurological problems. Case presentation: Three-month-old-boy with a familial history of HFM presented to the clinic due to persistent fatigue, yellowish discoloration, feeding refusal, and pancytopenia. The patient received 3 packs of Red Blood Cells (RBCs). Five days after received 3 packs of RBCs, the patient presented with a fever of 38.3 Celsius with pancytopenia. The patient had low level of all immunoglobulins. He was started on broad-spectrum antibiotics. Testing for the HFM's SLC46A1 gene mutation, was positive. The patient was started on Leucovorin and Respirm. Clinical discussion: In this case, HFM presented as a neutropenic fever, hypoimmunoglobulinemia, low serum folate, elevated homocysteine, and a positive mutation on the SLC46A1. HFM has a wide-spectrum of presentations which includes hematological, neurological, immunological and gastrointestinal. Treatment involves the administration of folinic acid in either oral or intramuscular injections. Conclusion: HFM can present as neutropenic fever. High index of suspension is to be maintained when the presenting symptoms of the patients vary over a large number of systems. Genetic counseling is needed for parents when both are carrying an autosomal recessive allele.

4.
Ann Med Surg (Lond) ; 78: 103723, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35600191

RESUMO

Introduction and importance: Factor V deficiency is a rare bleeding disorder with varying presentations from minor mucosal bleeding to a life-threatening postoperative bleed. Currently, treatment is mainly supportive with Fresh Frozen Plasma. Case presentation: A previously healthy 14-day-old male presented with an uncontrollable bleeding following a circumcision. Physical examination was normal. Investigations showed hemoglobin 15.5 g/dl, platelets 409000, Prothrombin Time 57 seconds, Partial-Thromboplastin-Time 120 seconds. Mixing study corrected the coagulation profile, and the factor assay showed factor V activity of 11%. Genetic testing showed a pathogenic frameshift mutation in the F5 gene p.(P927Lfs*7) causing premature termination after 7 codons thus the diagnosis of Factor V deficiency was made. Clinical discussion: In this case, factor V deficiency presented as post-circumcision bleeding. For diagnosis, increased PT and PTT with normal thrombin time increases the index of suspicion for a bleeding disorder. Further testing with coagulation factors assays is required to make the final diagnosis. Factor V deficient patients undergoing surgery should be adequately prepared, and factor V activity level should be maintained at least at 25% of the normal activity level. The patient level prior to the circumcision was unknown, which led to the life threatening bleed. Conclusions: One of the early presentations of factor V deficiency is a post-circumcision bleeding. Adequate preparation with laboratory tests before circumcision is therefore recommended, especially for high-risk individuals. More than 100 genetic mutations were detected; frameshift mutation involving F5 gene p.(P927Lfs*7) was seen in our case.

5.
Gen Psychiatr ; 33(5): e100227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32875273

RESUMO

Major depressive disorder (MDD) is a common, serious, debilitating condition affecting 350 million people worldwide, which remains to be unsatisfactorily treated with 53% of patients still complaining of symptoms after completing their courses with the correct dosage. Ketamine, which was approved by the Food and Drug Administration in 2019, is a potential treatment option for those recalcitrant cases. The mechanism of ketamine is not fully understood, but as type it is classified as an N-methyl-D-aspartate (NMDA) glutamate receptor antagonist, and can be given intravenously, intranasally and orally. It is used to treat treatment-resistant depression, depression associated with suicidal ideation, mood and anxiety disorders and depressions associated with either type of bipolar disorder. Although ketamine is considered relatively safe, several side effects have been reported with the major ones being psychiatric in the form of worsening mood, anxiety and agitation; psychotomimetic in the form of dissociation, perceptual disturbance and abnormal sensations; cardiovascular in the form of increased blood pressure and increased heart rate; and neurological in the form of headache and dizziness. Ketamine is still not approved worldwide for usage in patients with treatment-resistant MDD, but if it is approved sometime in the future with relatively fewer side effects, it is expected to significantly save millions of dollars spent yearly on patients with treatment-resistant depression and that will lift this major burden off the shoulders of healthcare professionals. This study was designed to measure the effects of ketamine, an NMDA receptor antagonist, on patients with treatment-resistant MDD and to analyse the concept that makes it different and relatively safer than other major antidepressants like selective serotonin reuptake inhibitors, monoamine oxidase inhibitors and TCAs (tricyclic antidepressants).

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