[Correlation analysis between lactic, procalcitonin and disease severity in patients with imported malaria from Africa].

Objective: To explore the clinical characteristics, the correlation between lactate, procalcitonin and disease severity of imported malaria from Africa. Methods: The clinical data of 186 patients with imported malaria were collected from January 1, 2018 to April 30, 2021 in the Guangzhou Eighth People's Hospital, Guangzhou Medical University. The general conditions, clinical symptoms, laboratory tests, treatment, and prognosis of the patients were analyzed retrospectively. Receiver operating characteristic (ROC) curves were drawn to evaluate the value of relevant indicators in predicting severe malaria. Results: A total of 186 patients were divided into severe cases (n=48) and non-severe cases (n=138) in this study, of which the mean age was (38.3±10.3) years, 169(90.9%) cases were male, 17(9.1%) cases were female. The main infection species was Plasmodium falciparum, in a total of 166 cases (89.2%). The severe cases were all falciparum malarias. Compared with the non-severe group, the lactic, procalcitonin, white blood cell count and neutrophil count of the severe group were all increased, the differences were all statistically significant (all P<0.01); the percentage of monocytes, red blood cell count, hemoglobin, hematocrit and platelet count were all decreased, the difference were all statistically significant (all P<0.01). The areas under the ROC curves (AUC)(95%CI) of lactate, procalcitonin, red blood cell count, hemoglobin, hematocrit and platelet count for predicting severe malaria was 0.753(0.663-0.844), 0.755(0.670-0.841), 0.782(0.700-0.864), 0.738(0.652-0.823), 0.760(0.676-0.844), 0.778(0.699-0.857), respectively (all P<0.01). When the Youden indexes were at their maximum, the best cut-off value of lactic was 2.29 mmol/L, with sensitivity in predicting of severe malaria was 56.3%, and the specificity was 93.5%; the best cut-off value of procalcitonin was 2.12 µg/L, with sensitivity in predicting of severe malaria was 77.1%, and the specificity was 68.1%. The fatality rate of severe malaria was 4.2% (2/48). Conclusions: Anemia and thrombocytopenia are common indicators for predicting the severity of malaria. Lactic and procalcitonin also have higher predictive value for severe malaria, which could help to identify severe malaria as early as possible, improve the cure rate and reduce the risk of death.

Multi-mJ, 200-fs, cw-pumped, cryogenically cooled, Yb,Na:CaF2 amplifier.

Using a novel (to our knowledge) broadband Yb-doped Yb3+,Na+:CaF2 crystal cooled in a closed loop to 130 K we demonstrate a chirped pulse regenerative laser amplifier delivering the energy of up to 3 mJ at a repetition rate of 1 kHz and an average output power of 6 W at 20 kHz. The gain narrowing in the laser crystal is compensated by shaping the amplitude of the seed pulse spectrum. As the result, at the highest amplified pulse energy we obtain a 12 nm FWHM bandwidth supporting a 130 fs pulse duration, assuming ideal compression. Amplified pulses were recompressed from 250 ps to 195 fs with a 1700 lines/mm transmission grating compressor.

Generation of radially polarized beam with a segmented spiral varying retarder.

We convert a linearly polarized Gaussian beam into a radially polarized doughnut beam with an eight-segment spirally varying retarder (SVR) at wavelength of 808 nm. The SVR is designed based on the linear birefringence of alpha-barium borate (alpha-BBO) crystal and fabricated using a dry etching process. Radially polarized light of high purity (> 96% at far-field distribution) was generated experimentally using the segmented SVR positioned between two quarter waveplates with orthogonal slow axes. The emergent polarization can be switched between radially and azimuthally polarized cylindrical vector beams with a pair of half-wave plates.

Fast switchable electro-optic radial polarization retarder.

A fast and switchable electro-optic radial polarization retarder (EO-RPR) fabricated using the electro-optic ceramic Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) is presented. This EO-RPR is useful for fast and switchable generation of a pure cylindrical vector beam. When used together with a pair of half-wave plates, the EO-RPR can change circularly polarized light into any cylindrical vector beam of interest, such as radially or azimuthally polarized light. Radially and azimuthally polarized light with purities greater than 95% are generated experimentally. The advantages of using EO-RPR include fast response time, low driving voltage, and transparency in a wide spectral range (500 to 7,000 nm).

Mimicking optical activity for generating radially polarized light.

We propose a new scheme for generating radially polarized light by mimicking optical activity using linear birefringence. It involves a birefringent spirally varying retarder sandwiched between two orthogonally oriented quarter-wave plates. Using Poincaré sphere representation, we show that the polarization transformation of such a scheme is equivalent to that of a spirally varying optical activity and is capable of generating radially polarized light. We demonstrate the proof-of-concept using y-cut crystalline quartz.

Simple coherent polarization manipulation scheme for generating high power radially polarized beam.

We present a simple novel scheme that converts a Gaussian beam into an approximated radially polarized beam using coherent polarization manipulation together with Poynting walk-off in birefringent crystals. Our scheme alleviates the interferometric stability required by previous schemes that implemented this coherent mode summation using Mach-Zehnder-like interferometers. A symmetrical arrangement of two walk-off crystals with a half-wave plate, allows coherence control even when the laser has short temporal coherence length. We generated 14 watts of radially polarized beam from an Ytterbium fiber laser, only limited by the available fiber laser power.

Why we consistently use the left donor kidney in living related transplantation: initial experience of right laparoscopic donor nephrectomy and comparison with left nephrectomy.

OBJECTIVES: Laparoscopic donor nephrectomy has become the method of choice for removal of living donor kidneys. However, the majority of laparoscopic donor nephrectomy cases have been limited to the left side owing to technical difficulties and renal vessel length. This study described the technique and compared donor outcomes and graft function of right and left laparoscopic donor nephrectomy. MATERIALS AND METHODS: Among 25 patients, 6 consecutive donors underwent right laparoscopic donor nephrectomy from March 2002 to January 2005. They were compared to 19 patients with left laparoscopic donor nephrectomy. We compared operative times, warm ischemia times, serial creatinines, creatinine clearances, complications, and graft function. RESULTS: There was no significant difference in any metric. The operative times (303 min. vs 274 min., P > .05) and warm ischemia times (133 s vs 186 s, P > .05) were similar between right and left laparoscopic donor nephrectomy procedures. In left laparoscopic donor nephrectomy, 3 patients had transient brachial plexus neuropathies. No major complication occurred among patients undergoing right laparoscopic donor nephrectomy. This study demonstrated that both donor and recipient outcomes are similar for right and left laparoscopic donor nephrectomy. CONCLUSIONS: Consistent use of the left kidney has not affected clinical outcomes. With hand-assisted laparoscopy, the right laparoscopic donor nephrectomy is safe, providing excellent graft function.

Kidney ultrasound is useful tool in posttransplant follow-up.

OBJECTIVES: Renal sonography has been an important imaging tool in surveys of kidney diseases. We reviewed our experience in the finding and management of asymptomatic patients who underwent renal transplantation. METHODS: We performed baseline graft and native kidney sonography after renal transplantation, as well as annually even if the patient was asymptomatic. At the end of 2004, a total of 326 transplant cases had been annually surveyed. If the findings were positive, they were compared with previous data to determine the need for further examinations and management. RESULTS: The native kidneys of 105 patients were abnormal. Cysts were detected in 71 cases, 23 of which were bilateral. Stones were found in 15 cases. Polycystic kidney disease was identified in 5. The findings in these 91 patients were the same as before. Moderate hydronephrosis was observed in 14 cases. Nine had native ureteral cancer and underwent nephroureterectomy. Ureteral stricture was found in the other 5 patients. Forty-five grafts were abnormal. Thirty-one showed hydronephrosis and 2 underwent ureteral reimplantation. Asymptomatic stones were found in 2. A new single renal cyst was found in 2 cases; and multiple cysts in one other. Elevated RI on color Doppler was discovered in 12 patients, 4 of whom lost their grafts this year. Serum creatinine values of 6.9 and 2.2 mg/dL were observed in 2 patients. CONCLUSIONS: Renal sonography screening is useful not only for the graft but also for the native kidney. Hydronephrosis is an important finding. The high possibility of urothelial malignancy should be expected, requiring further examination and sequential follow-up. Elevated RI is a clue to predict graft outcome; rapid deterioration was observed within months.

Silent urothelial cancer detected by sonography after renal transplantation.

OBJECTIVES: Organ transplantation increases the incidence of cancer through unclear mechanisms. In our observation, urothelial cancer happens much more frequently in Chinese people. We reviewed the detection of urothelial cancer in our series after renal transplantation. METHODS: From July 1981 to June 2005, we performed 620 renal transplantations. We do graft and native kidney sonography survey annually even if the patient is asymptomatic. During this period, 10 urothelial tumors were detected. Herein we have reviewed the findings in these cases, along with their management and outcomes. RESULTS: Moderate to severe hydronephrosis of native kidneys was observed in 14 patients, including 9 (64.3%) who had cancer including eight asymptomatic and only one with flank pain and lymph nodes metastasis succumbing in 10 months with a functioning graft. Three patients showed similar degrees of graft hydronephrosis and graft ureteral cancer was diagnosed in one. Mean time from transplantation was 5.09 years. There was a female predominance (7:3). The bladder-to-renal pelvis-to-ureter ratio was 2:5:7, which was distinct from the usual 51:3:1 distribution. In native ureter cancer, we found the left ureter more prone to develop cancer than the right (8:1). CONCLUSION: The pattern of cancer in renal transplant patients is thoroughly different from the general population, namely female predominance, with a higher incidence of ureteral and renal pelvis versus bladder cancer. In our observation, routine periodic sonography survey even in asymptomatic patients is important for urothelial tumor detection, as the incidence of cancer is surprisingly high.

Is sirolimus a safe alternative to reduce or eliminate calcineurin inhibitors in chronic allograft nephropathy in kidney transplantation?

PURPOSE: We evaluate whether cyclosporine (CsA) or tacrolimus (FK) could be reduced or eliminated after sirolimus was added in chronic allograft nephropathy (CAN). By reducing doses of CsA or FK, we expected that renal function would improve. METHOD AND MATERIAL: Twenty-one patients with CAN had sirolimus added as an immunosuppressive agent. We evaluated the creatinine (Cr) level 3 months after addition. The doses of CsA and FK were decreased gradually and then eliminated over a course of 4 to 6 weeks. If the Cr level rose rapidly or other prominent signs of rejection occurred; low-dose CsA or FK would be added per protocol. We evaluated the duration of engraftment before sirolimus and the Cr level when it was added. RESULTS: Renal function improved in 13 of 21 cases. The improvement in Cr ranged from 12.5% maximally to 1.84% minimally. Seven of 13 cases still required low-dose CsA. The average duration of engraftment before sirolimus was 13.66 +/- 10.80 months. The average Cr level before sirolimus was 1.65 +/- 0.56 mg/dL. In the other eight cases, the Cr level kept rising from 5.1% to 20.4%. The average duration of engraftment was 88.38 +/- 42.21 months. The average Cr level before sirolimus was 2.85 +/- 0.54 mg/dL. Hyperuricemia was noted in 31.3% and hyperlipidemia in 68.8%. CONCLUSION: Sirolimus is a safe alternative to reduce or eliminate CsA or FK in CAN. In cases with a long duration of engraftment and high Cr level, sirolimus might have some effect as a substitute for CNI and thus prevent further nephrotoxicity.

Bidirectional optical bistability in a dual-pumped erbium doped fiber ring laser.

We investigate bidirectional optical wave propagations in a dual-pumped erbium doped fiber ring laser without isolator, and observe optical bistability behaviors. Consequently, we propose and construct a NOLM-NALM fiber ring laser to demonstrate and exploit this bidirectional optical bistability phenomenon in optical switching by introducing two tunable variable ratio couplers in the system. Numerical analyses based on the proposed laser structure have also been demonstrated corroborated with the experimental results.