Temperature effect on the nucleation of graphene on Cu (111)

Repeated thermal cycling by using an organic precursor is shown to be a successful technique for growing graphene on metal substrates. Having control on this process is of vital importance in producing large areas of high quality graphene with well-ordered surface characteristics, which leads us to investigate the effect of temperature on the microscopic mechanisms behind this process. Apart from being an important factor in the dissociation of the organic precursor and promoting the reactions taking place on the surface of the catalyst, temperature also plays a major role in the structure of the catalyst surface. First, we used eight thermal cycles to successfully grow graphene on the surface of Cu (111). Then, we employed Ab Initio Molecular Dynamics (AIMD) simulations to study graphene island alignment evolution at two temperatures. The results shed light on our experimental observations and those reported in the literature and point to the effectiveness of controlled thermal cycling in producing high quality graphene sheets on transition metal catalyst surfaces.

Repeated thermal cycling by using an organic precursor is shown to be a successful technique for growing graphene on metal substrates.     

Prenatal diagnosis of complete penoscrotal transposition with normal scrotum: Two case reports and review of the literature

Complete penoscrotal transposition is an extremely rare congenital anomaly and is usually associated with other urinary system abnormalities. Prenatal diagnosis is feasible by demonstrating perineal anatomy and its relation with scrotum and phallus. We describe two prenatal cases presenting with oligohydramniosis and megacystis due to lower urinary tract obstruction. Postnatal diagnosis was confirmed in both cases. Considering the dismal perinatal outcome, an accurate prenatal diagnosis is required for counseling the parents and preparing for postnatal care.     

Therapeutic plasma exchange in patients with thrombotic thrombocytopenic purpura: A retrospective multicenter study

Thrombotic thrombocytopenic purpura (TTP) is a particular form of thrombotic microangiopathy typically characterized by thrombocytopenia, microangiopathic hemolytic anemia, fever, neurological abnormalities, and renal dysfunction. TTP requires a rapid diagnosis and an adapted management in emergency. Daily sessions of therapeutic plasma exchange (TPE) remain the basis of management of TTP. Also, TTP is a rare disease that is fatal if it is not treated. TPE has resulted in excellent remission and survival rates in TTP patients.AimWe aimed to present our experience in 163 patients with TTP treated with TPE during the past 5 years from 10 centers of Turkey.Patients and methodsOne hundered and sixty-three patients with TTP treated with TPE during the past 5 years from 10 centers of Turkey were retrospectively evaluated. TPE was carried out 1–1.5 times plasma volume. Fresh frozen plasma (FFP) was used as the replacement fluid. TPE was performed daily until normalization of serum lactate dehydrogenase (LDH) and recovery of the platelet count to >150 × 10⁹/dL. TPE was then slowly tapered. Clinical data, the number of TPE, other given therapy modalities, treatment outcomes, and TPE complications were recorded.ResultsFifty-eight percent (95/163) of the patients were females. The median age of the patients was 42 years (range; 16–82). The median age of male patients was significantly higher than female (53 vs. 34 years; p < 0.001). All patients had thrombocytopenia and microangiopathic hemolytic anemia. At the same time, 82.8% (135/163) of patients had neurological abnormalities, 78.5% (128/163) of patients had renal dysfunction, and 89% (145/163) of patients had fever. Also, 10.4% (17/163) of patients had three of the five criteria, 10.4% (17/163) of patients had four of the five criteria, and 6.1% (10/163) of patients had all of the five criteria. Primary TTP comprised of 85.9% (140/163) of the patients and secondary TTP comprised of 14.1% (23/163) of the patients. Malignancy was the most common cause in secondary TTP. The median number of TPE was 13 (range; 1–80). The number of TPE was significantly higher in complete response (CR) patients (median 15.0 vs. 3.5; p < 0.001). CR was achieved in 85.3% (139/163) of the patients. Similar results were achieved with TPE in both primary and secondary TTP (85% vs. 87%, respectively; p = 0.806). There was no advantage of TPE + prednisolone compared to TPE alone in terms of CR rates (82.1% vs. 76.7%; p = 0.746). CR was not achieved in 14.7% (24/163) of the patients and these patients died of TTP related causes. There were no statistical differences in terms of mortality rate between patients with secondary and primary TTP [15% (21/140) vs. 13% (3/23); p = 0.806]. But, we obtained significant statistical differences in terms of mortality rate between patients on TPE alone and TPE + prednisolone [14% (12/86) vs. 3% (2/67), p < 0.001].ConclusionsTPE is an effective treatment for TTP and is associated with high CR rate in both primary and secondary TTP. Thrombocytopenia together with microangiopathic hemolytic anemia is mandatory for the diagnosis of TTP and if these two criteria met in a patient, TPE should be performed immediately.     

Acitretin treatment in acrokeratosis verruciformis of Hopf

Acrokeratosis verruciformis of Hopf is a rare disorder and characterized by flesh-coloured, wart-like, flat papules on the dorsum of the hands and feet. The disease is an autosomal disorder, but sporadic cases also occur. We present a 38-year-old woman diagnosed with acrokeratosis verruciformis without family history and treated successfully with acitretin.