[Clinical analysis of 10 patients with Fabry disease]

We aimed to analyze the clinical data of 10 patients (6 male and 4 female) with Fabry disease (FD). The mean age of the patients was (28.80±9.27) years. Seven patients had classical FD and three had delayed onset FD. Among the 10 patients, six had skin involvement and cutaneous angiokeratoma; five had hypohidrosis or anhidrosis; nine had intermittent neuralgia; and three had supraorbital ridge protrusion, forehead bulge, and lip thickening. Five patients had proteinuria, including one with chronic kidney disease stage 3 and one with chronic kidney disease stage 5. Cardiac involvement occurred in three patients, two had myocardial hypertrophy and one had valvular insufficiency. The activity of galactosidase decreased in seven patients (2.80-1.55 μmol·L-1·h-1). Plasma deacetyl-GL-3 was elevated in all 10 patients(3.12-120.00 ng/ml). Three patients underwent renal biopsy, wherein two cases of focal segmental glomerulosclerosis and one of mesangial proliferative glomerulonephritis was found. A large number of myeloid and zebra bodies were found in the podocytes in three patients, including a small number of myeloid and zebra bodies in the renal tubular epithelial cells in one patient with occasional zebra bodies in the renal interstitium. Nine patients had GLA gene mutations. One patient was c.102T>A, a de novo mutation. Four patients were treated with agalsidase α injection (0.2 mg/kg, intravenous infusion every 2 weeks), and their prognosis was good. FD has various clinical manifestations and multi-system involvement, which requires multidisciplinary cooperation. Detection of galactosidase activity, plasma globotriaosylsphingosine, and GLA gene mutation can help for accurate diagnosis.

[Application of target trail emulation in real world: a case study of effect of statins on mortality in diabetes patients]

Target trail emulation is an observational research method, which can use real-world data (such as observational data and historical data) to carry out research design according to the design principles of randomized controlled trials (RCT) when RCT cannot be carried out. The intervention group and the control group were classified by simulating random grouping. Finally a high-reliable conclusion similar to RCT can be obtained. This paper summarizes the basic concepts and application process of target trail emulation based on the effect of statins on the prognosis of myocardial infarction in diabetic patients to provide reference for the application of this method in real world.

[Efficacy and outcomes of shunt surgery for secondary hydrocephalus]

Records of secondary hydrocephalus patients undergoing shunt surgery in the Department of Neurosurgery of Peking Union Medical College Hospital from September 2012 to April 2022 and their clinical characteristics and outcomes were retrospectively reviewed and analyzed. Among 121 patients who received first time shunt placement, the most common causes of secondary hydrocephalus were brain hemorrhage (55, 45.5%) and trauma (35, 28.9%). Cognition decline (106, 87.6%), abnormal gait (50, 41.3%) and incontinence (40, 33.1%) were the most prevalent manifestations. Postoperative central nervous system infection (4, 3.3%), shunt obstruction (3, 2.5%) and subdural hematoma/effusion (4, 3.3%) were the most frequent neurological complications. Overall incidence of postoperative complications was 9% (11 cases) in the current cohort. And 50.5% (54/107) of the patients receiving shunting achieved a Glasgow outcome scale (GOS) score of at least 4. Shunt surgery is preferred for secondary hydrocephalus, especially for secondary normal pressure hydrocephalus. Moreover, it is recommended to complete cranioplasty in staged operation or one-stage operation for the patients with decompressive craniectomy.

Electrical-gate-controlled giant tunneling magnetoresistance and its quasi-periodic oscillation in an interlaced magnetic-electric silicene superlattice

In this work, we propose a silicene-based lateral resonant tunneling device by placing silicene under the superlattices interlaced, arranged by ferromagnetic gates and electric gates. Its ballistic transport properties are calculated by the transfer matrix method. Combined with the unique electrically tuned energy gap of silicene, its magnetoresistance (MR) can be exaggeratedly modulated over a wide range by applying electrostatic potential and the on-site potential difference. It is interestingly found that there is a quasi-periodic oscillation of the MR in silicene-based superlattice devices from the quantum resonant confinement of the band splitting by the electrostatic field. Moreover, the peak of the MR in a single-period structure can reach more than 10⁴, while the peak of the MR in an interlaced alternating magnetic-electric silicene superlattice can reach more than 10¹⁷, which is one of the best-reported values. This may originate from the enhancement effect of the wave vector filtering by the controlled field. Our studies indicate that the silicene superlattices alternately arranged by the ferromagnetic gate and electric gate not only have giant MR (GMR) properties, but also exhibit the periodic oscillation characteristics of MR in which electric gates can be modulated. Therefore, this work provides a more flexible strategy for the construction of silicene-based nanoelectronic devices.

[Clinical characteristics of 6 children with idiopathic interstitial pneumonia]

Objective: To analyze the clinical characteristics and prognosis of 6 children with idiopathic interstitial pneumonia (IIP). Methods: This retrospective study analyzed the clinical manifestations, examinations, treatment and prognosis of 6 children with IIP who were hospitalized in Children's Hospital of Nanjing Medical University from January 2015 to March 2020. Results: Of the 6 children, 2 were males and 4 were females, aged 4.8 to10.6 years. All children had a subacute onset, and presented with cough, shortness of breath and cyanosis. The lung high-resolution CT (HRCT) showed diffuse patchiness in bilateral lung fields in all the children and reticular pattern in 2 cases. Pulmonary function test found moderate to severe mixed defect in 5 children. Lung biopsy was performed in 4 children. All of the 6 children were treated with systemic glucocorticoids, of whom 2 cases had additional inhaled glucocorticoids. Four children were finally diagnosed as cryptogenic organizing pneumonia (COP), whose lung HRCT return to normal in 1-11 months. Two children were finally diagnosed as nonspecific interstitial pneumonia (NSIP), and had long-term residual fibrosis on lung HRCT. The 6 children were followed up for 1 year to 6 years and 5 months after discontinuation of systemic glucocorticoids, and all had no recurrence. Conclusions: The clinical characteristics of IIP in children are subacute onset presented with cough, shortness of breath, cyanosis and diffuse patchiness in bilateral lungs on HRCT. The common subtypes of IIP in children are COP and NSIP. Systemic glucocorticoid is effective for IIP in children and there is a good prognosis overall.

[Critical care management and thinking of perihematomal edema after intracerebral hemorrhage]

The prognosis of patients with spontaneous intracerebral hemorrhage (sICH) is poor. It is of great significance to improve the neurological function of these patients and make them return to society. However, to date, no treatment has been proved to significantly improve the neurological prognosis of sICH patients. The perihematomal edema (PHE) is a quantifiable marker of secondary brain injury (SBI) after ICH. It is associated with dysfunction of ion channels of vascular endothelial cells, inflammatory response induced-blood brain barrier dysfunction, and iron deposition caused by red blood cell degradation after ICH. Given that the space-occupying effect of PHE, the direct relation with SBI, long growth course and variable growth of PHE among individuals, interrupting the expansion of PHE has become a therapeutic target to improve neurological outcomes in ICH patients. Conducting an integrated and individualized strategy of critical care management and performing the corresponding pre-clinical and translational clinical research targeting the pathophysiological mechanism, nature course, and risk factors of PHE deserves further exploration.

GaOx@GaN Nanowire Arrays on Flexible Graphite Paper with Tunable Persistent Photoconductivity

Flexible optoelectronic synaptic devices that functionally imitate the neural behavior with tunable optoelectronic characteristics are crucial to the development of advanced bioinspired neural networks. In this work, amorphous oxide-decorated GaN nanowire arrays (GaO_x@GaN NWAs) are prepared on flexible graphite paper. A GaO_x@GaN NWA-based flexible device has tunable persistent photoconductivity (PPC) and shows a conversible fast/slow decay process (SDP). Photoconductivity can be modulated by single or double light pulses with different illumination powers and biases. PPC gives rise to the high-performance SDP such as a long decay time of 2.3 × 10⁵ s. The modulation mechanism is proposed and discussed. Our results reveal an innovative and efficient strategy to produce decorated NWAs on a flexible substrate with tunable optoelectronic properties and exhibit potential for flexible neuromorphic system applications.

[Updated key points of Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 edition)]

Led by the China Pituitary Adenoma Specialist Council, the Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 Edition) is developed combined with the research progress of pituitary growth hormone (GH)-secreting adenoma both at home and abroad, evidence-based evidence of the diagnosis and treatment of acromegaly, and China's national conditions. Based on the guideline for acromegaly (2013 Edition), the new version of consensus emphasizes the importance of multidisciplinary team (MDT) and individual therapy. The criteria for control of acromegaly is discussed. Pathological criteria for the diagnosis of pituitary GH-secreting adenoma is updated. New developments in surgery, drug and radiotherapy are introduced. Meanwhile, the diagnosis and treatment of acromegaly patients concurrent with other particular scenarios, including pregnancy and refractory pituitary GH-secreting adenoma is suggested. This article aims to describe the updated key points of the new version of the consensus, and thus facilitate the clinical implementation of standardized diagnosis and treatment for acromegaly patients.

[Application of apparent diffusion coefficient histogram in moderate to severe neonatal hypoxic-ischemic encephalopathy]

Objective: To investigate the diagnostic value of apparent diffusion coefficient (ADC) histogram in quantifying moderate to severe neonatal hypoxic-ischemic encephalopathy (HIE). Methods: A total of 49 children with moderate to severe HIE admitted to the Children's Hospital Affiliated to Nanjing Medical University from July 2015 to September 2018 were retrospectively analyzed. Cranial magnetic resonance imaging (MRI) data of 31 full-term neonates without neurological symptoms and signs who visited the hospital during the same period were recruited as the control group. ImgJ software was used to delineate the whole brain area at the thalamus/basal ganglia level as the area of interest, and MRIcron software was used to obtain ADC histogram parameters. The differences of ADC histogram parameters between HIE group and control group were compared. The correlation between ADC histogram parameters and neonatal neurobehavioral neurological assessment (NBNA) in HIE group was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficiency of each parameter. Results: The mean value, minimum value, maximum value, mode-value, variance, heterogeneity and 10%-90% ADC values of HIE group were all greater than those of the control group(634±65,310±36,1 683±18,711±87,66 928±921,5 907±204,477±50,513±53,542±56,568±59,591±61,625±92,661±97,709±105,811±119),the differences were statistically significant(all P<0.05), while mode-count of HIE group was smaller than that of the control group(272±22 to 395±83), and the difference was statistically significant (t=2.996,P<0.05). All the above parameters with statistical differences were correlated with NBNA score, among which mode-count was negatively correlated with NBNA score(r=-0.369,P<0.05), and the rest were positively correlated(all P<0.05). The area under the ROC curve (AUC) of variance had the highest diagnostic efficiency (0.881), followed by 90% ADC value and ADC maximum value. Conclusion: ADC histogram is helpful for the diagnosis of HIE, objectively and quantitatively reflecting the diffusion information of brain, and assessing the severity of HIE.

Additively manufactured biomedical Ti-Nb-Ta-Zr lattices with tunable Young's modulus: Mechanical property, biocompatibility, and proteomics analysis

Some β-Ti alloys, such as Ti-Nb-Ta-Zr (TNTZ) alloys, exhibit a low Young's modulus and excellent biocompatibility. These alloys are promising new generation biomedical implant materials. Selective laser melting (SLM) can further enable customer-specific manufacturing of β-Ti alloys to satisfy the ever-increasing need for enhanced biomedical products. In this study, we quantitatively determined the relationships between porosity, yield strength, and Young's modulus of SLM-prepared TNTZ lattices. The study constitutes a critical step toward understanding the behavior of the lattice and eventually enables tuning the Young's modulus to match that of human bones. Fatigue properties were also investigated on as-printed lattices in terms of the stress limit. The biocompatibility study included a routine evaluation of the relative cell growth rate and a proteomics analysis using a common mouse fibroblast cell line, L929. The results indicated that the as-printed TNTZ samples exhibited evidence of protein proliferation of the L929 cells, particularly P06733, and that those proteins are responsible for biological processes and molecular functions. They in turn may have promoted cell regeneration, cell motility, and protein binding, which at least partially explains the good biocompatibility of the as-printed TNTZ at the protein level. The study highlights the promising applications of additively manufactured TNTZ as a bone-replacing material from mechanical and biocompatibility perspectives.

Solar PV-Battery-Electric Grid-Based Energy System for Residential Applications: System Configuration and Viability

Distributed renewable energy share increase in electricity generation is creating challenges for the whole power system, due to its intermittent and nonprogrammable nature. Energy storage has the potential to solve those issues although its technical, economic, and environmental impact is up for debate. The paper presents a study about a PV-battery energy storage system installed in a grid-connected residential apartment in the Green Energy Laboratory at Shanghai Jiao Tong University, China. Daily experimental results show how the presence of energy storage reduces the midday feed-in of excess PV power and the evening peak demand, providing benefits to the distribution network in terms of reduced voltage swings and peak load. Considering the Chinese context, an economic analysis is carried out to assess the profitability of residential PV-battery systems, using the net present value as the economic indicator of an 18-year investment in which the battery pack is replaced twice (6 life years). The analysis shows that such system is not economically viable due to a combination of low electricity prices, valuable PV incentives, and high technology costs. However, considering a future scenario of doubled electricity tariff, halved export tariff, and falling technology costs (-66% battery and -17% PV and inverter), PV-battery investment becomes profitable and shows more resilience to future scenarios than PV-only investment.

[Performance of Knosp grade for cavernous sinus invasion of Cushing's disease]

Objective: To review the outcomes in patients with Cushing's disease (CD) after transsphenoidal surgery (TSS) and to assess the performance of Knosp grade for cavernous sinus invasion (CSI). Methods: Medical records were reviewed for patients with CD undergoing TSS from 1978 to 2017 at Peking Union Medical College Hospital. Based on whether CSI was observed during surgery, the sensitivity and specificity of Knosp grade for CSI were evaluated. Results: There were 1 061 records of CD reviewed, 83 (7.82%) of which were invasive tumors evaluated by surgery, and 44 (53.0%) of these remained in endocrinological remission at the last follow-up. The sensitivity of Knosp grade for CSI was 47.0%, and the specificity was 91.1%; besides, the positive predictive value was 31.0%, and the negative predictive value was 95.3%. Conclusions: Initial TSS for CD with invasive adenomas is of relatively low remission rate. Knosp grade 0-2 for non-invasive tumors is reliable, while it is doubtful whether or not Knosp grade 3-4 indicates invasive tumor.

Coupling enhanced growth by nitrogen and hydrogen plasma of carbon nanotubes

Coupling growth mechanism with N* and H*.

[The surgical treatment in adults with idiopathic normal pressure hydrocephalus]

Objective: To investigate the effect of Ventriculoperitoneal shunt (VPS)in adult patients with idiopathic normal pressure hydrocephalus (iNPH). Methods: The patients with idiopathic normal pressure hydrocephalus were reviewed, who were admitted into the Peking union medical college hospital from October 2010 to October 2016.The patients treated via VPS were retrospectively analyzed by collecting the data including clinic features, iNPH score and imaging data. Results: 33 patients were included in the group.3 months after operation, the iNPH scores were significantly decreased (3.0±1.0 vs 6.0±2.5, P<0.01), and there were no difference among 3 month, 6 month and 12 month post operation.The Evans index and the width of the three ventricles were also significantly decreased.1 patient suffered from subdural hematoma and no other complications such as infection, obstruction or death occurred. Conclusions: VPS is an effective treatment approach of iNPH and multidisciplinary team is the key in diagnosis.

[Cost-effectiveness analysis of octreotide long acting release and lanreotide slow release for the treatment of postoperative patients with active acromegaly in China]

Objective: To evaluate the cost-effectiveness of octreotide long acting release (LAR) vs lanreotide slow release (SR) for the treatment of postoperative acromegalic patients with elevated levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) in China. Methods: A decision tree model was constructed and the treatment impact was projected for one year in Chinese setting. The clinical efficacy measure used was the percentage of patients achieving normalization (control) of either IGF-1 or GH levels. Efficacy of octreotide LAR and lanreotide SR, incidence of comorbidities, impact of acromegaly on health-related quality of life, and drug-related side effects data were obtained from literature. The cost of medication was collected through a chart review from five hospitals in five cities of China. Clinical experts from these hospitals were requested to complete a questionnaire to document the utilization of medical resources, costs of comorbidities, side effects as well as cost of administration. One-way sensitivity analysis was performed to evaluate the robustness of the results. Results: Compared to lanreotied SR group, the percentage of patients achieving normalization of IGF-1 and GH levels of octreotide LAR group were 10% and 9% higher, respectively. When either IGF-1 or GH control were used as the efficacy measure, patients in the octreotide LAR group exhibit less comorbidities and need less continued treatment with a second operation and radiotherapy than those in lanreotide SR group. When IGF-1 was used as efficacy measure, octreotide LAR not only achieved better efficacy but resulted in overall cost-saving, with a total cost savings of ￥ 3 792 per patient for one year, which demonstrated that octreotide LAR was a dominant cost-saving strategy. When GH control was used as the efficacy measure, octreotide LAR achieved a better overall clinical efficacy with a slightly higher total costs (￥ 4 121 higher per patient per year). Sensitivity analysis didn't change the conclusion that octreotide LAR remains dominant over lanreotide SR, indicating the robustness of this model. Conclusion: Octreotide LAR achieved better overall biochemical control compared with lanreotide SR which result in less comorbidity rate, second operation and radiotherapy as well as related costs.

[The localization diagnosis of patients with adrenocorticotropic hormone-dependent Cushing's syndrome in adolescence]

Objective: To elucidate the clinical characteristics and localization diagnosis of patients with adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (CS) in adolescence. Methods: The clinical data, laboratory examination and localization diagnosis from 35 patients aged less than 18 years old with adolescent CS who were treated at Peking Union Medical College Hospital between January 1990 and March 2012 were analyzed. Results: There were 29 cases of Cushing's disease (CD) and 6 cases of ectopic ACTH syndrome (EAS). Compared to patients with EAS, those with CD were older at diagnosis[(15.2±2.7) vs (12.8±4.4) years], and had longer disease course[(1.9±1.5) vs (0.7±0.3) years]and higher serum potassium[(3.8±0.6) vs (2.5±0.7) mmol/L], however the plasma ACTH level[(15.4±14.9) vs (42.5±22.7) pmol/L]was lower (all P<0.05). If the cut-off of the ratio of 24-hour urine free cortisol (24 h UFC) after low-dose dexamethasone suppression test (LDDST) to before LDDST was 0.65, the sensibility to diagnose CD was 70.8%, and the specificity was 100%. If the cut-off of the 24 h UFC ratio after high-dose dexamethasone suppression test (HDDST) to before HDDST was 0.54, the sensibility to diagnose CD was 91.7%, and the specificity was 100%. If the cut-off of the plasma ACTH ratio of inferior petrosal vein[bilateral inferior petrosal sinus sampling (BIPSS)]to peripheral vein was 2, only 6 CD patients (6/8) met it. Conclusion: The study suggested that HDDST was more meaningful in the localization diagnosis of patients with ACTH-dependent CS in adolescence.

[The diagnosis and treatment of systemic lupus erythematosus complicated with hydrocephalus]

Objective: To investigate the pathogenesis and management of the hydrocephalus in patients with systemic lupus erythematosus (SLE). Methods: Eight cases of hospitalized lupus patients with hydrocephalus in Peking Union Medical College Hospital from Jan 1990 to Mar 2017 were analyzed retrospectively.We collected the patients' medical records including medical history, CT and/or MRI images and analysis of cerebrospinal fluid via lumbar puncture in order to investigate the pathogenesis of the hydrocephalus in patients with SLE and summarize treatment experience. Results: All the 8 patients with SLE complicated with hydrocephalus were treated with steroids or immunosuppressive agents, and 5 cases were diagnosed with the central nervous system infection. Three cases received ventriculoperitoneal shunt, 5 cases received treatment of medicine.They all were followed up for 2-12 months, of which 3 cases were markedly effective, 1 case effective and 4 cases dead. Conclusion: The pathogenesis of lupus combined with hydrocephalus may have a certain relationship with the central infection, should take effective anti-infection treatment.We recommend cerebrospinal fluid shunt surgery intervention.

Generalized Mechanism of Field Emission from Nanostructured Semiconductor Film Cathodes

Considering the effect of both the buffer layer and substrate, a series of ultrathin multilayered structure cathodes (UTMC) is constructed to simulate the field emission (FE) process of nanostructured semiconductor film cathodes (NSFCs). We find a generalized FE mechanism of the NSFCs, in which there are three distinct FE modes with the change of the applied field. Our results clearly show significant differences of FE between conventional emitters and nanofilm emitters, which the non-Fowler-Nordheim characteristics and the resonant FE will be inevitable for NSFCs. Moreover, the controllable FE can be realized by fine-tuning the quantum structure of NSFCs. The generalized mechanism of NSFCs presented here may be particularly useful for design high-speed and high-frequency vacuum nano-electronic devices.

[Perioperative management and surgical treatment of neurosurgical critical patients with thrombocytopenia]

OBJECTIVE

To study the perioperative management and surgical treatment of patients with neurosurgical critical diseases and thrombocytopenia.

METHODS

Eleven patients with the diagnosis of neurosurgical critical diseases and thrombocytopenia who received surgical treatment in Department of Neurosurgery, Peking Union Medical College Hospital from 2010 to 2015 were reviewed retrospectively. All eleven patients received platelet transfusions preoperatively. The safety and efficacy of surgical treatment were analyzed by GOS score at 6 months after operations.

RESULTS

Platelet counts of six patients who received minimally invasive surgery reached 80×10(9) /L by platelet transfusions preoperatively. Platelet counts of five patients who received Craniotomy and ventriculoperitoneal shunt reached 100×10(9) /L by platelet transfusions preoperatively. Eight patients received platelet transfusions postoperatively according to a low platelet count 24 hours after operations. Two patients died after surgery and one died after discharge. All other eight survival patients got well recovery with an average GOS score of 4.5 at six months after operations.

CONCLUSIONS

Patients with neurosurgical critical diseases and thrombocytopenia could receive surgical treatment in collaboration with relative departments.

[Analysis of outcomes and learning curve of endoscopic transsphenoidal surgeries for 124 patients with pituitary adenomas]

OBJECTIVE

To investigate the outcomes of the Endoscopic transsphenoidal surgery for patients with pituitary adenomas, analyze the learning curve and provide reference for future surgeries.

METHODS

Retrospective analysis was carried out on 124 patients by endoscopic transsphenoidal surgery with a single neurosurgeon over a period spanning from January 2010 to January 2014 at Peking Union Medical College Hospital.The changes of endocrine and tumor imaging before and after surgery were analysed. Operative time and complication rates of one surgeon in the early period of learning curve were compared with that in later period.

RESULTS

There were significant differences in Gross total resection (GTR) rate of pituitary adenomas with different sizes and different Knosp classifications (P<0.01, P<0.01). GTR rate of huge adenomas was significantly lower than that of macroadenoma and adenomas (P<0.05). GTR rate of Knosp 4 grade adenoma was significantly lower than that of Knosp 0-3 level (P<0.05). No significant difference in GTR among all types of functional pituitary adenomas and hormone levels after surgery was observed (P>0.05). In addition, no significant difference (P>0.05) in complications among different sizes, Knosp grade and type of pituitary adenomas was observed.GTR of Knosp 4 adenoma in later period of the learning curve was significantly higher than that in early period (P<0.05). Meanwhile the operative time was significantly lower than early period (P<0.05).

CONCLUSIONS

Endoscopic transsphenoidal pituitary adenoma resection has the advantages of wider surgical field, higher GTR rate, less trauma, fewer complications and better life quality of patients.Through standardized learning, the GTR rate of the invasive pituitary adenomas can be improved.

Comfortable, high-efficiency heat pump with desiccant-coated, water-sorbing heat exchangers

Comfortable, efficient, and affordable heating, ventilation, and air conditioning systems in buildings are highly desirable due to the demands of energy efficiency and environmental friendliness. Traditional vapor-compression air conditioners exhibit a lower coefficient of performance (COP) (typically 2.8–3.8) owing to the cooling-based dehumidification methods that handle both sensible and latent loads together. Temperature- and humidity-independent control or desiccant systems have been proposed to overcome these challenges; however, the COP of current desiccant systems is quite small and additional heat sources are usually needed. Here, we report on a desiccant-enhanced, direct expansion heat pump based on a water-sorbing heat exchanger with a desiccant coating that exhibits an ultrahigh COP value of more than 7 without sacrificing any comfort or compactness. The pump’s efficiency is doubled compared to that of pumps currently used in conventional room air conditioners, which is a revolutionary HVAC breakthrough. Our proposed water-sorbing heat exchanger can independently handle sensible and latent loads at the same time. The desiccants adsorb moisture almost isothermally and can be regenerated by condensation heat. This new approach opens up the possibility of achieving ultrahigh efficiency for a broad range of temperature- and humidity-control applications.

Analysis of bromocriptine treatment in pregnant pituitary prolactinoma patients

OBJECTIVE

To investigate the therapeutic effects and duration of bromocriptine treatment during pregnancy in patients with pituitary prolactinoma.

MATERIALS AND METHODS

A retrospective analysis of the clinical data of 230 female pituitary prolactinoma patients at the Beijing Union Medical College Hospital neurosurgery clinic from January 2001 to May 2014 was conducted. When confirmed pregnant, patients in the control group immediately stopped taking bromocriptine, but patients in the treatment group continued to take the same dose of bromocriptine.

RESULTS

The embryos stop rate in the control group was 16.7%, significantly higher than the rate in the natural population (p < 0.05), while the rate in the treatment group (0.9%) not statistically different from that of the natural population (p > 0.05). There was no significant difference in the embryonic malformation rate between the two study groups compared to the normal pregnancy group (p > 0.05).

CONCLUSION

Pregnant pituitary prolactinoma patients should not stop bromocriptine treatment, but should instead continue with the same dose for four months. For patients with macroadenoma, bromocriptine should be taken during the entire pregnancy. Blood prolactin, progesterone, human chorionic gonadotropin (hCG), and visual dysfunction should be monitored every two weeks during treatment. Patients should be treated with progesterone and hCG if the blood levels become too low. If regular monitoring shows that prolactin has increased too fast and/or visual dysfunction worsened, the dose of bromocriptine should be in- creased. The authors have found that bromocriptine treatment during pregnancy significantly reduces the embryo stop rate without in- creasing the embryo deformity rate; therefore, bromocriptine treatment is safe and necessary during pregnancy of pituitary prolactinoma patients.

[The surgery of thyrotropin-secreting pituitary adenomas and the significance of thyroid stimulating hormone level in follow-up]

Objective: To explore the clinical characteristics of thyrotropin-secreting pituitary adenomas and the effect of the transsphenoidal approach of procedure with/without drug treatment for thyrotropin-secreting pituitary adenomas, and to investigate the correlation between the prognosis of thyrotropin-secreting pituitary adenomas and the postoperative level of thyroid stimulating hormone (TSH). Methods: A total of 45 patients with thyrotropin-secreting pituitary adenoma who hospitalized in Peking Union Medical College Hospital from 2000 to 2015 were enrolled in the study.We collected the clinical features, hormone levels, imaging findings, treatment and follow-up data of these patients. Results: The average age of the patients was 40.26 years old and the average disease duration was 5.83 years.Among them, 8 cases were microadenomas and 37 cases were macroadenoma.Thirty patients were treated with somatostatin analogues before surgery.TSH level was significantly decreased after operation (P=0.012). All of them had done the pituitary surgery, including 44 transsphenoidal surgery and 1 subfrontal surgery that had recurrence one year after the transsphenoidal surgery.The TSH level of 34 cases went back to normal on the third day after surgery.The remission rates on three months and one year after surgery in patients with TSH level<0.1 mIU/L on postoperative day (POD) 3 were significantly higher than those in patients with TSH level>0.1 mIU/L on POD3.As well as the remission rates on three months and one year after surgery in patients with TSH level normal on postoperative one month were significantly higher than those in patients with TSH level abnormal on postoperative one month. Conclusions: TSH level of postoperative one month could be used to predict prognosis and monitor recurrence.

[The value and comparison of plasma adrenocorticotropic hormone and urinary free cortisol in predicting long-term outcome after operation of Cushing's disease]

Objective: To study and the value of morning plasma adrenocorticotropic hormone (ACTH) and urinary free cortisol (24 h UFC) within 3 days after operation in patients with Cushing's disease in predicting the long-term outcome. Methods: The clinical data of 140 patients with Cushing's disease who were treated in Department of Neurosurgery of PUMCH from 2012 to 2014 were analyzed retrospectively.The univariate analysis, multivariate Logistic analysis, ROC curve analysis and other statistical methods were used to study the predicting value of morning plasma ACTH and 24 h UFC in 3 days post operation. Results: Univariate analysis showed that in the two groups of the early remission and no remission, there was significant statistical difference between the preoperative ACTH, preoperative 24 h UFC, postoperative ACTH and postoperative 24 h UFC (P<0.05, <0.01, <0.01). Logistic analysis showed that ACTH and 24 h UFC after operation of two groups had significant difference (P<0.01, <0.05). ROC curve analysis showed that postoperative cutoff values of ACTH and 24 h UFC were 4.11 pmol/L (18.7 pg/ml) and 281.42 nmol (102 μg)/24 h. ROC analysis was performed to evaluate the predicting performance of postoperative ACTH, resulting in an area under the curve (AUC) of 0.917 (95%CI: 0.858-0.957, P<0.01). In comparison, 24 h UFC had an AUC of 0.814 (95%CI: 0.739-0.875, P<0.01). The predicting value of ACTH is significantly better than that of 24 h UFC (P=0.005). Conclusion: Early morning 24 h UFC and ACTH within 3 days after operation both showed considerable accuracy in predicting the long-term outcome of Cushing's disease, and the significance of ACTH was even greater than that of 24 h UFC.

An atomistic mechanism study of GaN step-flow growth in vicinal m-plane orientations

Elucidation of homoepitaxial growth mechanisms on vicinal non-polar surfaces of GaN is highly important for gaining an understanding of and control thin film surface morphology and properties. Using first-principles calculations, we study the step-flow growth in m-plane GaN based on atomic row nucleation and kink propagation kinetics. Ga-N dimer adsorption onto the m-plane is energetically more favorable than that of Ga and N isolated adatoms. Therefore, we have treated the dimers as the dominant growth species attached to the step edges. By calculating the free energies of sequentially attached Ga-N dimers, we have elucidated that the a-step edge kink growth proceeds by parallel attachment rather than by across the step edge approach. We found a series of favorable configurations of kink propagation and calculated the free energy and nucleation barriers for kink evolution on five types of step edges (a, +c, -c, +a + c, and -a - c). By changing the chemical potential μ_Ga and the excess chemical potential Δμ, the growth velocities at the five types of edges are controlled by the corresponding kink pair nucleation barrier E* in their free energy profiles. To explore the kink-flow growth instability observed at different Ga/N flux ratios, calculations of kink pairs on the incompact -c and +c-step edges are further performed to study their formation energies. Variations of these step edge morphologies with a tuned chemical environment are consistent with previous experimental observations, including stable diagonal ±a ± c-direction steps. Our work provides a first-principles approach to explore step growth and surface morphology of the vicinal m-plane GaN, which is applicable to analyze and control the step-flow growth of other binary thin films.

Elastic Properties, Defect Thermodynamics, Electrochemical Window, Phase Stability, and Li(+) Mobility of Li3PS4: Insights from First-Principles Calculations

The improved ionic conductivity (1.64 × 10(-4) S cm(-1) at room temperature) and excellent electrochemical stability of nanoporous β-Li3PS4 make it one of the promising candidates for rechargeable all-solid-state lithium-ion battery electrolytes. Here, elastic properties, defect thermodynamics, phase diagram, and Li(+) migration mechanism of Li3PS4 (both γ and β phases) are examined via the first-principles calculations. Results indicate that both γ- and β-Li3PS4 phases are ductile while γ-Li3PS4 is harder under volume change and shear stress than β-Li3PS4. The electrochemical window of Li3PS4 ranges from 0.6 to 3.7 V, and thus the experimentally excellent stability (>5 V) is proposed due to the passivation phenomenon. The dominant diffusion carrier type in Li3PS4 is identified over its electrochemical window. In γ-Li3PS4 the direct-hopping of Lii(+) along the [001] is energetically more favorable than other diffusion processes, whereas in β-Li3PS4 the knock-off diffusion of Lii(+) along the [010] has the lowest migration barrier. The ionic conductivity is evaluated from the concentration and the mobility calculations using the Nernst-Einstein relationship and compared with the available experimental results. According to our calculated results, the Li(+) prefers to transport along the [010] direction. It is suggested that the enhanced ionic conductivity in nanostructured β-Li3PS4 is due to the larger possibility of contiguous (010) planes provided by larger nanoporous β-Li3PS4 particles. By a series of motivated and closely linked calculations, we try to provide a portable method, by which researchers could gain insights into the physicochemical properties of solid electrolyte.

[Use early morning serum cortisollevel to evaluate the effect of Cushing's disease after transsphenoidal surgery]

OBJECTIVE

To predict the therapeutic effect of Cushing's disease after transsphenoidal surgery by using morning serum cortisol level.

METHODS

The clinical data of 275 cases that had transsphenoidal surgery in Peking Union Medical College Hospital from 2010 to 2014 were analyzed retrospectively.Early morning serum cortisol level less than 140 nmol/L 3 days postoperation was usedto predict endocrinological remission. And long-term efficacy was evaluated by follow-up.

RESULTS

Of the 275 patients, there were 49 males and 226 females; average age was 36.5 years old.Remission wasconfirmed in 201 cases, the remission rate was 73.1%, and 8 cases recurrent duringfollow-up.There were 17 macroadenomas, theremission rate was 47.1%; 258 microadenomas and MRI negative adenomas, the remission rate was 74.8%.And 43 recurrent cases had reoperations; the remission rate was 46.5%.

CONCLUSION

Early morningserum cortisol 3 days post operation can evaluate the effectof transsphenoidal surgery, but even if the level of cortisol is less than 140 nmol/L, there is still tumor recurrence.Patients should be follow-up for a lifetime.

[Comparison of efficacy between the serum cortisol and 24 hour urine free cortisol in combined dexamethasone suppression test in the diagnosis of Cushing syndrome]

OBJECTIVE

To compare the sensitivity and specificity between the 24 hour urine free cortisol (24 h UFC) and serum cortisol in dexamethasone suppression test (DST) in the diagnosis of Cushing syndrome (CS).

METHODS

Combined low dose DST (LDDST) and high dose DST (HDDST) were carried out in 67 cases of CS with surgically confirmed cases in recent 3 years(from January 2011 to November 2015). The serum cortisol and 24 h UFC were collected simultaneously for each subject and the sensitivity and specificity of serum cortisol and 24 h UFC were compared.

RESULTS

There were Cushing disease (CD) group (n=53), ectopic adrenocorticotropic hormone (ACTH) syndrome group (n=7) and ACTH-independent Cushing syndrome group (n=7) according to the etiology of hypercorticordism.There were no significant differences among 3 groups in gender and age.The sensitivity of serum cortisol of different cut off points(50, 110, 140 nmol/L and 50% of control)after LDDST was 97.01%, 86.57%, 83.58% and 70.15% respectively.Meanwhile, the sensitivity of cutoff point of 24 h UFC <32 nmol in combined LDDST was 92.54% in the diagnosis of Cushing syndrome.There was no significant differences in two groups between serum cortisol <110 nmol/L and 24 h UFC <32 nmol.However, the sensitivity of serum cortisol <50 nmol/L was significantly higher than 24 h UFC<32 nmol (P<0.05). Furthermore, in combined HDDST, if the suppression rate was ≥50%, the sensitivity of serum cortisol and 24 h UFC in differentiating the etiology of Cushing disease was 60.38% and 90.57%, and the specificity was 91.43% and 96.00% respectively.There were significant differences between serum cortisol and 24 h UFC in both of sensitivity and specificity (both P<0.05). In addition, if the suppression rate of 24 h UFC in HDDST was adjusted to 60.85% according to receiver operating characteristic (ROC) curve, it could have the best levels of sensitivity (92.6%) with the specificity of 85.7%. If the suppression rate of serum cortisol was adjusted to 61.53% in HDDST according to ROC curve, it could have the best sensitivity (64.8%) with the specificity of 78.6% accordingly.

CONCLUSION

In combined LDDST, the serum cortisol <50 nmol/L had a higher sensitivity than the 24 h UFC<32 nmol when they were used as the criteria in determining the diagnosis of CS.In HDDST, the sensitivity and specificity of suppression rate of 24 h UFC ≥50% were better than serum cortisol to differentiate the etiology of CS.

Engineering of hydrogenated two-dimensional h-BN/C superlattices as electrostatic substrates

Hybridized two-dimensional materials incorporating domains from the hexagonal boron nitride (h-BN) and graphene is an interesting branch of materials science due to their highly tunable electronic properties. In the present study, we investigate the hydrogenated two-dimensional (2D) h-BN/C superlattices (SLs) with zigzag edges using first-principles calculations. We found that the domain width, the phase ratio, and the vertical dipole orientation all have significant influence on the stability of SLs. The electronic reconstruction is associated with the lateral polar discontinuities at the zigzag edges and the vertically polarized (B2N2H4)(m) domains, which modifies the electronic structures and the spatial potential of the SLs significantly. Furthermore, we demonstrate that the hydrogenated 2D h-BN/C SLs can be applied in engineering the electronic structure of graphene: laterally-varying doping can be achieved by taking advantage of the spatial variation of the surface potential of the SLs. By applying an external vertical electric field on these novel bidirectional heterostructures, graphene doping levels and band offsets can be tuned to a wide range, such that the graphene doping profile can be switched from the bipolar (p-n junction) to unipolar (n(+)-n junction) mode. It is expected that such bidirectional heterostructures provide an effective approach for developing novel nanoscale electronic devices and improving our understanding of the fundamentals of low-dimensional materials.

Defects in AIN/GaN Superlattice: First Principle Calculations

In this paper we investigate the atomic configurations, electronic structure and formation energies of native point defects, (such as vacancies and self-interstitials), in an AIN/GaN superlattice (SL) constructed on a wurtzite structure along a [0001] growth direction. Comprehensive first-principle calculations based on the density functional theory (DFT) are used. Cation and anion vacancies in the neutral charge state are calculated. For the native defects, the results showed that the most favorable configurations are the cation vacancies at the interface of the SL, or the anion vacancies in the GaN wells. Considering the formation energies of different vacancies, the results show that the nitrogen vacancy has the lowest formation energy, indicating that they are significantly the most stable configuration, and thus should be expected to be the major defect in a AIN/GaN superlattice.

Self-templating noncatalyzed synthesis of monolithic boron nitride nanowires

Achieving economic orientation-controlled growth of monolithic nanowires remains a challenge.

Bipolar doping of double-layer graphene vertical heterostructures with hydrogenated boron nitride

Using first-principles calculations, we examined the bipolar doping of double-layer graphene vertical heterostructures, which are constructed by hydrogenated boron nitride (BN) sheets sandwiched into two parallel graphene monolayers.

Association of polymorphisms of the xeroderma pigmentosum complementation group F gene with increased glioma risk

We aimed to investigate the role of 4 single nucleotide polymorphisms of the xeroderma pigmentosum complementation group F (XPF) gene (rs3136038, rs1799798, rs1800067, and rs2276466) in glioma, and the roles of gene-gene interactions in the risk of developing this type of cancer. We collected samples from 225 glioma cases and 262 controls and genotyped the rs3136038, rs1799798, rs1800067, and rs2276466 polymorphisms using a 384-well plate format with the Sequenom MassARRAY platform. Individuals carrying the rs1800067 GG genotype were more likely to have an increased risk of glioma when compared with carriers of the A/A genotype in a co-dominant model, with an odds ratio (OR) [95% confidence interval (CI)] of 2.85 (1.14-7.76). However, we did not find an association with increased risk of glioma for the polymorphisms rs3136038, rs1799798, and rs2276466 in XPF. The combination genotype of the rs1800067 G allele and the rs2276466 G allele was associated with a moderate risk of glioma (OR = 1.71, 95%CI = 1.02-2.87). Our study suggests that the rs1800067 genetic variant of XPF functions in the development of glioma.

Two dimensional Dirac carbon allotropes from graphene

Using a structural search method in combination with first-principles calculations, we found lots of low energy 2D carbon allotropes and examined all possible Dirac points around their Fermi levels. Three amazing 2D Dirac carbon allotropes have been discovered, named as S-graphene, D-graphene and E-graphene. By analyzing the topology correlations among S-, T, net W graphene and graphene, we found that a general rule is valuable for constructing 2D carbon allotropes that are keen to possess Dirac cones in their electronic structures. Based on this rule, we have successfully designed many new 2D carbon allotropes possessing Dirac cones. Their energy order can be well described by an Ising-like model, and some allotropes are energetically more stable than those recently reported. The related electronic structures of these Dirac allotropes are anisotropy distinguished from those of graphene. Moreover, the fact that D- and E-graphene present Dirac cones suggests that sp hybridization or sp(3) hybridization could not suppress the emerging of Dirac features. Our results demonstrate that the Dirac cone and carrier linear dispersion is a very common feature in 2D carbon allotropes and can exist beyond the limitations of fundamental structure features of graphene.

Modified morphology of graphene sheets by Argon-atom bombardment: molecular dynamics simulations

By a molecular dynamics method, we simulated the process of Argon-atom bombardment on a graphene sheet with 2720 carbon atoms. The results show that, the damage of the bombardment on the graphene sheet depends not only on the incident energy but also on the particle flux density of Argon atoms. To compare and analyze the effect of the incident energy and the particle flux density in the Argon-atom bombardment, we defined the impact factor on graphene sheet by calculating the broken-hole area. The results indicate that, there is an exponential accumulated-damage for the impact of both the incident energy and the particle flux density and there is a critical incident energy ranging from 20-30 eV/atom in Argon-atom bombardment. Different configurations, such as sieve-like and circle-like graphene can be formed by controlling of different particle flux density as the incident energy is more than the critical value. Our results supply a feasible method on fabrication of porous graphene-based materials for gas-storages and molecular sieves, and it also helps to understand the damage mechanism of graphene-based electronic devices under high particle radiation.

Computed tomography-guided aspiration versus key-hole craniotomy for spontaneous putaminal haemorrhage: a prospective comparison of minimally invasive procedures

OBJECTIVES

To compare the effectiveness of two minimally invasive procedures, namely computed tomography-guided aspiration and the key-hole approach, in the neurosurgical management for spontaneous putaminal haemorrhage, and to explore the indications for the two approaches.

DESIGN

A multicentre, single-blinded controlled trial.

SETTING

Hospitals taking part in this trial and the sources for patients were from China. Among others, the hospitals involved in the interventions included: the Beijing Tiantan Hospital (of the Capital University of Medical Sciences), the General Hospital of People's Liberation Army, the Peking Union Hospital, and the Shanghai Huashan Hospital (of the Fudan University medical school).

PATIENTS

From September 2001 to November 2003, data were available for analysis from a total of 841 patients with spontaneous putaminal haemorrhage from 135 hospitals all over China (except Tibet, Hong Kong, Taiwan, and Macao). All follow-up data were for at least 3 months.

MAIN OUTCOME MEASURES

Mortality, Glasgow Coma Scale score, postoperative complications, Kanofsky Performance Scale score, and Barthel Index.

RESULTS

There were 563 patients who underwent computed tomography-guided aspiration, and 165 were treated by the key-hole approach. Respective mortality rates 1 month after the operation were 17.9% and 18.3%; at 3 months they were 19.4% and 19.4%. In those undergoing computed tomography-guided aspiration, mortality rates at 3 months after the operation were 28.2% in patients with Glasgow Coma Scale scores of 8 or below, as opposed to 8.2% in those with higher scores. This amounted to a 3.4-fold difference. In those treated by the key-hole approach, the corresponding rates were 30.2% and 7.6%, which amounted to a 4-fold difference. The corresponding mortality at 3 months in patients with complications was 3.9 times as great as in those without complications. In those with haematoma volumes of 70 mL or greater, it was 2.7 times as much as in those in whom the volumes below 30 mL. The postoperative complication rate of computed tomography-guided aspiration (23.7%) did not differ significantly from that in those having the key-hole approach (25.7%) [P=0.420].

CONCLUSIONS

Computed tomography-guided aspiration is not superior to the key-hole approach for treating spontaneous putaminal haemorrhage in terms of favourable outcomes, mortality, and morbidity. However, it could be the first-choice approach for those with bleeds of 50 mL or less, while the key-hole approach may be more suitable for those with larger haematomas.

Performance evaluation of a novel liquid nitrogen cryoprobe

A novel liquid nitrogen cryoprobe is developed in the present study. The inlet, handle, the vapor-liquid separator and the heat transfer segment of the cryoprobe are designed to be detachable. This flexible construction provides many distinct features, such as good maneuverability, high safety and low cost. A new vapor-liquid separator is made to ensure the free flow of the liquid nitrogen and increase the probe freezing capacity. The wall temperatures at the different locations along the cryoprobe are measured in the air, gel and brine, with the various driven pressure ranging from 0.3 to 0.6 MPa. The results are compared to the other probe. It is found that the precooling time of the probe is shortened significantly. The present cryoprobe offers better cooling performance to the existing cryoprobe. The heat flux transferred from the surrounding air or brine to the cryoprobe is estimated, and it is concluded that the boiling pattern in the probe is the film boiling and suggestions for further improvement of the cryoprobe's performance is made based on the analysis.