[Technology specification of bedside hypertonic saline-contrast electrical impedance tomography of lung perfusion and clinical application]

Bedside hypertonic saline-contrast electrical impedance tomography (EIT) method for lung perfusion evaluation has several advantages of bedside, simple, noninvasive and radiation-free. For a long time, EIT perfusion image of hypertonic saline was mostly limited to animal experiments, and related clinical research is in the ascendant. This technical specification for clinical application is reached based on our previous researches, review of literatures in this field. The purpose of this technical specification is to facilitate the unified and standardized use of hypertonic saline-contrast EIT technology for regional lung perfusion, to evaluate the safety and quality control of the technology, and to unify the results.

A smartphone ocular alignment measurement app in school screening for strabismus

Background

Strabismus is the leading risk factor for amblyopia, which should be early detected for minimized visual impairment. However, traditional school screening for strabismus can be challenged due to several factors, most notably training, mobility and cost. The purpose of our study is to evaluate the feasibility of using a smartphone application in school vision screening for detection of strabismus.

Methods

The beta smartphone application, EyeTurn, can measure ocular misalignment by computerized Hirschberg test. The application was used by a school nurse in a routine vision screening for 133 elementary school children. All app measurements were reviewed by an ophthalmologist to assess the rate of successful measurement and were flagged for in-person verification with prism alternating cover test (PACT) using a 2.4Δ threshold (root mean squared error of the app). A receiver operating characteristic (ROC) curve was used to determine the best sensitivity and specificity for an 8Δ threshold (recommended by AAPOS) with the PACT measurement as ground truth.

Results

The nurse obtained at least one successful app measurement for 93% of children (125/133). 40 were flagged for PACT, of which 6 were confirmed to have strabismus, including 4 exotropia (10△, 10△, 14△ and 18△), 1 constant esotropia (25△) and 1 accommodative esotropia (14△). Based on the ROC curve, the optimum threshold for the app to detect strabismus was determined to be 3.0△, with the best sensitivity (83.0%), specificity (76.5%). With this threshold the app would have missed one child with accommodative esotriopia, whereas conventional screening missed 3 cases of intermittent extropia.

Conclusions

Results support feasibility of use of the app by personnel without professional training in routine school screenings to improve detection of strabismus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01902-w.

[Analysis of clinical features, gene mutation, and prognostic characteristics in de novo acute myeloid leukemia patients with myelofibrosis]

目的

探讨初诊急性髓系白血病（AML）合并骨髓纤维化（MF）患者的基因突变、临床及预后特征。

方法

2016年1月1日至2020年2月1日河南省人民医院收治的初诊并同时行骨髓活组织检查的103例AML患者纳入研究，根据WHO（2016）骨髓纤维化分级标准将患者分为AML伴MF组（MF-1～3）与AML不伴MF组（MF-0），并对两组患者的临床特征、基因突变、疗效和预后进行回顾性比较。

结果

①103例患者中AML伴MF组46例（44.7％），其中MF-1 39例（84.8％），MF-2/3 7例（15.2％）；AML不伴MF组57例（55.3％）。和AML不伴MF组相比，AML伴MF组中位WBC显著增高［11.205（0.69～191.82）×10⁹/L对4.64（0.18～95.10）×10⁹/L，P＝0.024］；外周血出现有核红细胞的比例明显增高（43.5％对24.6％，χ²＝4.119，P＝0.042）；FAB分型：4例AML-M₀患者均在AML伴MF组，而AML不伴MF组AML-M₂所占比例更高（P＝0.014）。②AML伴MF组患者FLT3-ITD及NPM1基因突变率更高（15.2％对1.8％，P＝0.021；26.1％对10.5％，P＝0.039），而CEBPA基因突变率明显低于AML不伴MF组（2.2％对17.5％，P＝0.029）。③AML伴MF组完全缓解（CR）率显著低于AML不伴MF组（69.7％对93.2％，χ²＝7.412，P＝0.006）。多因素分析显示MF，尤其是纤维化程度是影响初诊AML患者CR的独立危险因素。④AML伴MF组3年总生存（OS）率明显低于AML不伴MF组（20.5％对72.2％，χ²＝4.032，P＝0.045）；亚组分析显示MF-1和MF-2/3两组患者的OS率、无进展生存（PFS）率显著低于AML不伴MF组（P＝0.001）。Cox多因素分析显示MF，尤其是MF-2/3是影响初诊AML患者OS和PFS的独立危险因素（P值分别为0.021和0.044）。

结论

AML合并MF患者具有较为独特的实验室及临床特征；MF是影响AML患者CR、OS和PFS的独立预后不良指标，MF的评估对初诊AML的疗效和预后判断具有重要意义。

SNHG16 promotes the progression of osteoarthritis through activating microRNA-93-5p/CCND1 axis

OBJECTIVE

This study aims to investigate whether SNHG16 (small nucleolar RNA host gene 16) can promote the progression of osteoarthritis (OA) by regulating the microRNA-93-5p/Cyclin D1 (CCND1) axis, thereby finding new therapeutic targets for the treatment of OA.

PATIENTS AND METHODS

A total of 23 OA patients and 23 patients undergoing lower extremity amputation were enrolled in this study. We collected their cartilage tissues from knee joint for isolating chondrocytes. The relative levels of SNHG16, CCND1 and microRNA-93-5p in cartilage tissues of OA patients and controls were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The regulatory effect of SNHG16 on proliferative potential of chondrocytes was evaluated by Cell Counting Kit-8 (CCK-8) and colony formation assay, respectively. Cell cycle progression was examined using flow cytometry. Dual-Luciferase reporter gene assay was conducted to verify the binding between SNHG16 with microRNA-93-5p and microRNA-93-5p with CCND1. Rescue experiments were performed to elucidate whether SNHG16 regulated CCND1 expression by targeting microRNA-93-5p.

RESULTS

The expressions of SNHG16 and CCND1 upregulated, while microRNA-93-5p downregulated in cartilage tissues of OA patients relative to controls. Correlation regression analyses showed a negative expression correlation between SNHG16 and microRNA-93-5p, as well as CCND1 and microRNA-93-5p in OA patients. On the contrary, SNHG16 expression was positively correlated to CCND1 expression in OA. The knockdown of SNHG16 suppressed viability, cloning ability and cell cycle progression, but induced apoptosis in chondrocytes. Dual-Luciferase reporter gene assay showed that SNHG16 could bind to microRNA-93-5p. SNHG16 knockdown markedly upregulated the expression of microRNA-93-5p. Moreover, the knockdown of microRNA-93-5p reversed the inhibited viability due to SNHG16 knockdown. Transfection of microRNA-93-5p mimics markedly inhibited CCND1 expression. Importantly, CCND1 overexpression reversed the inhibitory effect of SNHG16 knockdown on chondrocyte viability.

CONCLUSIONS

SNHG16 promotes the development of OA by regulating microRNA-93-5p/CCND1 axis.

Successful interruption of seasonal influenza transmission under the COVID-19 rapid response in Zhejiang Province, China

Objectives

The objective of this study was to evaluate whether the non-pharmaceutical interventions (NPIs) introduced to curb the spread of coronavirus disease 2019 (COVID-19) also interrupted the transmission of influenza.

Study design

This is a descriptive epidemiological study.

Methods

Data on changes in the number of reported influenza cases, number of influenza-like illness (ILI) visits, ILI percentage and influenza virus positivity were compared between the first 18 weeks of 2020 and the same period of 2019.

Results

The changes in the weekly average number of influenza cases were statistically significant between 2020 and 2019 (−4319 vs −525 per week; P < 0.05). The slopes of regression lines for the number of ILI visits were also statistically significant between 2020 and 2019 (−911 vs −98 per week; P < 0.05).

Conclusions

This study found that the prevalence of influenza was substantially decreased when NPIs were implemented for the containment of COVID-19.

•

The prevalence of influenza was substantially decreased when non-pharmaceutical interventions were implemented for the containment of coronavirus disease 2019.

•

Changes in the weekly average number of influenza cases were statistically significant between 2020 and 2019 (−4319 vs −525 per week; P < 0.05).

•

Changes in the number of influenza-like illness visits were also statistically significant between 2020 and 2019 (−911 vs −98 per week; P < 0.05).

Ecosystem-based fisheries management forestalls climate-driven collapse

Climate change is impacting fisheries worldwide with uncertain outcomes for food and nutritional security. Using management strategy evaluations for key US fisheries in the eastern Bering Sea we find that Ecosystem Based Fisheries Management (EBFM) measures forestall future declines under climate change over non-EBFM approaches. Yet, benefits are species-specific and decrease markedly after 2050. Under high-baseline carbon emission scenarios (RCP 8.5), end-of-century (2075–2100) pollock and Pacific cod fisheries collapse in >70% and >35% of all simulations, respectively. Our analysis suggests that 2.1–2.3 °C (modeled summer bottom temperature) is a tipping point of rapid decline in gadid biomass and catch. Multiyear stanzas above 2.1 °C become commonplace in projections from ~2030 onward, with higher agreement under RCP 8.5 than simulations with moderate carbon mitigation (i.e., RCP 4.5). We find that EBFM ameliorates climate change impacts on fisheries in the near-term, but long-term EBFM benefits are limited by the magnitude of anticipated change.

Ecosystem Based Management measures developed to prevent overfishing could be particularly important under climate change. Here the authors combine climate and fish stock modelling to show that EBM cap implementation reduces climate-driven fishery declines under RCP 4.5 and 8.5 before midcentury. However, there are thermal tipping points beyond which potential collapses are predicted.

Target Area Extraction Algorithm for the In Vivo Fluorescence Imaging of Small Animals

Bio-optical imaging can noninvasively describe specific biochemical reaction events in small animals using endogenous or exogenous imaging reagents to label cells, proteins, or DNA. The fluorescence optical bio-imaging system excites the fluorescent group to a high energy state by excitation light and then generates emission light. However, many substances in the organism will also emit fluorescence after being excited by the excitation light, and the nonspecific fluorescence generated will affect the detection sensitivity. This paper designs and develops a set of high-level biosafety in vivo fluorescence imaging system for small animals suitable for virology research and proposes a target area extraction algorithm for fluorescence images. The fluorescence image target extraction algorithm first maps the nonlinear separation data in the low-dimensional space to the high-dimensional space. Then, based on the analysis of the characteristics of the fluorescent region, a method for discriminating the target fluorescent region based on the two-step entropy function is proposed, and the real target fluorescent region is obtained according to the set connected region. Based on the experiment of collecting and analyzing the in vivo fluorescent images of mice, it is verified that the proposed algorithm can automatically extract the target fluorescent region better than the classical linear model. It shows that the proposed algorithm is less affected by background fluorescence, and the estimated separated spectrum based on this method is closer to the real target spectrum.

Σ^{+} and Σ[over ¯]^{-} Polarization in the J/ψ and ψ(3686) Decays

From 1310.6×10^{6}  J/ψ and 448.1×10^{6}  ψ(3686) events collected with the BESIII experiment, we report the first observation of Σ^{+} and Σ[over ¯]^{-} spin polarization in e^{+}e^{-}→J/ψ[ψ(3686)]→Σ^{+}Σ[over ¯]^{-} decays. The relative phases of the form factors ΔΦ have been measured to be (-15.5±0.7±0.5)° and (21.7±4.0±0.8)° with J/ψ and ψ(3686) data, respectively. The nonzero value of ΔΦ allows for a direct and simultaneous measurement of the decay asymmetry parameters of Σ^{+}→pπ^{0}(α_{0}=-0.998±0.037±0.009) and Σ[over ¯]^{-}→p[over ¯]π^{0}(α[over ¯]_{0}=0.990±0.037±0.011), the latter value being determined for the first time. The average decay asymmetry, (α_{0}-α[over ¯]_{0})/2, is calculated to be -0.994±0.004±0.002. The CP asymmetry A_{CP,Σ}=(α_{0}+α[over ¯]_{0})/(α_{0}-α[over ¯]_{0})=-0.004±0.037±0.010 is extracted for the first time, and is found to be consistent with CP conservation.

Three-Dimensional Topotactic Host Structure-Secured Ultrastable VP-CNO Composite Anodes for Long Lifespan Lithium- and Sodium-Ion Capacitors

Performance degradation of lithium/sodium-ion capacitors (LICs/SICs) mainly originates from anode pulverization, particularly the alloying and conversion types, and has spurred research for alternatives with an insertion mechanism. Three-dimensional (3D) topotactic host materials remain much unexplored compared to two-dimensional (2D) ones (graphite, etc.). Herein, vanadium monophosphide (VP) is designed as a 3D topotactic host anode. Ex situ electrochemical characterizations reveal that there are no phase changes during (de)intercalation, which follows the topotactic intercalation mechanism. Computational simulations also confirm the metallic feature and topotactic structure of VP with a spacious interstitial position for the accommodation of guest species. To boost the electrochemical performance, carbon nano-onions (CNOs) are coupled with 3D VP. Superior specific capacity and rate capability of VP-CNOs vs lithium/sodium can be delivered due to the fast ion diffusion nature. An exceptional capacity retention of above 86% is maintained after 20 000 cycles, benefitting from the topotactic intercalation process. The optimized LICs/SICs exhibit high energy/power densities and an ultrastable lifespan of 20 000 cycles, which outperform most of the state-of-the-art LICs and SICs, demonstrating the potential of VP-CNOs as insertion anodes. This exploration would draw attention with regard to insertion anodes with 3D topotactic host topology and provide new insights into anode selection for LICs/SICs.

Study of Open-Charm Decays and Radiative Transitions of the X(3872)

The processes X(3872)→D^{*0}D[over ¯]^{0}+c.c.,γJ/ψ,γψ(2S), and γD^{+}D^{-} are searched for in a 9.0  fb^{-1} data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe X(3872)→D^{*0}D^{0}[over ¯]+c.c. and find evidence for X(3872)→γJ/ψ with statistical significances of 7.4σ and 3.5σ, respectively. No evident signals for X(3872)→γψ(2S) and γD^{+}D^{-} are found, and the upper limit on the relative branching ratio R_{γψ}≡{B[X(3872)→γψ(2S)]}/{B[X(3872)→γJ/ψ]}<0.59 is set at 90% confidence level. Measurements of branching ratios relative to decay X(3872)→π^{+}π^{-}J/ψ are also reported for decays X(3872)→D^{*0}D^{0}[over ¯]+c.c.,γψ(2S),γJ/ψ, and γD^{+}D^{-}, as well as the non-D^{*0}D^{0}[over ¯] three-body decays π^{0}D^{0}D^{0}[over ¯] and γD^{0}D^{0}[over ¯].

Determination of Strong-Phase Parameters in D→K_{S,L}^{0}π^{+}π^{-}

We report the most precise measurements to date of the strong-phase parameters between D^{0} and D[over ¯]^{0} decays to K_{S,L}^{0}π^{+}π^{-} using a sample of 2.93  fb^{-1} of e^{+}e^{-} annihilation data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. Our results provide the key inputs for a binned model-independent determination of the Cabibbo-Kobayashi-Maskawa angle γ/ϕ_{3} with B decays. Using our results, the decay model sensitivity to the γ/ϕ_{3} measurement is expected to be between 0.7° and 1.2°, approximately a factor of three smaller than that achievable with previous measurements, based on the studies of the simulated data. The improved precision of this work ensures that measurements of γ/ϕ_{3} will not be limited by knowledge of strong phases for the next decade. Furthermore, our results provide critical input for other flavor-physics investigations, including charm mixing, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes.

Recent advances of therapeutic targets and potential drugs of COVID-19

Since December 2019, numerous cases of coronavirus disease 2019 (COVID-19) caused by the infection of the novel coronavirus (2019-nCoV) have been confirmed in Wuhan, China. The outbreak of 2019-nCoV in China embodied a significant and urgent threat to global health. 2019-nCoV was a new, highly contagious coronavirus discovered following the outbreak of SARS coronavirus (SARS-CoV) and MERS coronavirus (MERS-CoV). The novel coronavirus can cause severe respiratory disease and even death. However, no specific therapeutic drugs have been developed clinically thus far. This article examines the potential of therapeutic drugs by assessing the structure of 2019-nCoV, its mechanism in invading host cells, and the anti-viral mechanism of the human autoimmune system. We also review the latest research regarding the progress of potential therapeutic drugs and provide references for new drug developments of COVID-19.

The Differential Expression of Cytokines and Growth Factors After SMILE Compared With FS-LASIK in Rabbits

Purpose

To investigate the differential expression of cytokines and growth factors in the cornea and aqueous humor after small incision lenticule extraction (SMILE) compared with femtosecond LASIK (FS-LASIK) using rabbit model.

Methods

Sixteen eyes of 16 rabbits in each group underwent SMILE or FS-LASIK with refractive correction of −6.00 DS/−1.00 DC. Eight additional rabbits served as controls. Pre- and 24 hours, 1 week, 1 month, and 3 months postoperatively, slit-lamp and anterior segment optical coherence tomography were performed, followed by cornea and aqueous humor collection. Apoptosis and proliferation were evaluated with TUNEL assay and Ki-67 immunostaining, respectively. The mRNA and protein expression of cytokines and growth factors was determined by RT-qPCR and Western blotting, respectively. Cytokine levels in the aqueous humor were detected with ELISA.

Results

Compared with FS-LASIK, SMILE induced less apoptosis and proliferation in the cornea within 1 week postoperatively. Levels of IL-1β, TNF-α, and EGFR in the cornea were significantly increased after FS-LASIK compared with SMILE within 24 hours. Levels of IL-8 in the aqueous humor remained elevated until 1 week after FS-LASIK but not SMILE. TGF-β1 level was elevated up to 1 month after both procedures, while BFGF level was kept high within 1 month after SMILE but not FS-LASIK.

Conclusions

SMILE could induce significantly less acute inflammation than FS-LASIK in the cornea and aqueous humor. The differential expression of TGF-β1 and BFGF between two procedures until 1 month might contribute to the post-SMILE delayed recovery and underline the importance of continued treatment postoperatively.

Observation of a Resonant Structure in e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0}

A partial-wave analysis is performed for the process e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0} at the center-of-mass energies ranging from 2.000 to 2.644 GeV. The data samples of e^{+}e^{-} collisions, collected by the BESIII detector at the BEPCII collider with a total integrated luminosity of 300  pb^{-1}, are analyzed. The total Born cross sections for the process e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0}, as well as the Born cross sections for the subprocesses e^{+}e^{-}→ϕπ^{0}π^{0}, K^{+}(1460)K^{-}, K_{1}^{+}(1400)K^{-}, K_{1}^{+}(1270)K^{-}, and K^{*+}(892)K^{*-}(892), are measured versus the center-of-mass energy. The corresponding results for e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0} and ϕπ^{0}π^{0} are consistent with those of BABAR with better precision. By analyzing the cross sections for the four subprocesses, K^{+}(1460)K^{-}, K_{1}^{+}(1400)K^{-}, K_{1}^{+}(1270)K^{-}, and K^{*+}(892)K^{*-}(892), a structure with mass M=(2126.5±16.8±12.4)  MeV/c^{2} and width Γ=(106.9±32.1±28.1)  MeV is observed with an overall statistical significance of 6.3σ, although with very limited significance in the subprocesses e^{+}e^{-}→K_{1}^{+}(1270)K^{-} and K^{*+}(892)K^{*-}(892). The resonant parameters of the observed structure suggest it can be identified with the ϕ(2170), thus the results provide valuable input to the internal nature of the ϕ(2170).

[Application of Chen's pancreaticojejunostomy technique in laparoscopic pancreaticoduodenectomy (116 cases report)]

Objective: To investigate the safety and feasibility of longitudinal transpancreatic U-sutures invaginated pancreatojejunostomy (Chen's pancreaticojejunostomy technique) in laparoscopic pancreaticoduodenectomy (LPD). Methods: Clinical data of 116 consecutive patients who underwent LPD using Chen's pancreaticojejunostomy technique in Hunan Provincial People's Hospital from May 2017 to December 2018 were retrospectively analyzed. Among these patients, 66 were males and 50 were females. The median age was 58 years old (32-84 yeas old). All 116 patients underwent pure laparoscopic whipple procedure with Child reconstruction method, using Chen's pancreaticojejunostomy technique. The intraoperative and postoperative data of patients were analyzed. Results: All 116 patients underwent LPD successfully. The mean operative time was (260.3±33.5) minutes (200-620 minutes). The mean time of pancreaticojejunostomy was (18.2±7.6) minutes (14-35 minutes). The mean time of hepaticojejunostomy was (14.6±6.3) minutes (10-25 minutes). The mean time of gastrojejunostomy was (12.0±5.5) minutes (8-20 minutes). The mean estimated blood loss was (106.0±87.6) ml (20-800 ml). Postoperative complications were: 11.2%(13/116) of cases had postoperative pancreatic fistula (POPF), including 10.3% (12/116) of biochemical fistula and 0.9%(1/116) of grade B POPF, no grade C POPF occurred; 10.3%(12/116) had gastrojejunal anastomotic bleeding; 3.4%(4/116) had hepaticojejunal anastomotic fistula; 3.4%(4/116) had delayed gastric emptying; 4.3% (5/116) had localized abdominal infection; 12.1%(14/116) had pulmonary infection; postoperative mortality were 0(0/116) and 1.7%(2/116) within 30 days and 90 days, respectively. One patient died of massive abdominal bleeding secondary to Gastroduodenal artery pseudoaneurysm rupture, the other patient died of extensive tumor recurrence and metastasis after surgery. Conclusions: Chen's pancreaticojejunostomy technique is safe and feasible for LPD.It is an option especially for surgeons who have not completed the learning curve of LPD.

Measurement of Proton Electromagnetic Form Factors in e^{+}e^{-}→pp[over ¯] in the Energy Region 2.00-3.08 GeV

The process of e^{+}e^{-}→pp[over ¯] is studied at 22 center-of-mass energy points (sqrt[s]) from 2.00 to 3.08 GeV, exploiting 688.5  pb^{-1} of data collected with the BESIII detector operating at the BEPCII collider. The Born cross section (σ_{pp[over ¯]}) of e^{+}e^{-}→pp[over ¯] is measured with the energy-scan technique and it is found to be consistent with previously published data, but with much improved accuracy. In addition, the electromagnetic form-factor ratio (|G_{E}/G_{M}|) and the value of the effective (|G_{eff}|), electric (|G_{E}|), and magnetic (|G_{M}|) form factors are measured by studying the helicity angle of the proton at 16 center-of-mass energy points. |G_{E}/G_{M}| and |G_{M}| are determined with high accuracy, providing uncertainties comparable to data in the spacelike region, and |G_{E}| is measured for the first time. We reach unprecedented accuracy, and precision results in the timelike region provide information to improve our understanding of the proton inner structure and to test theoretical models which depend on nonperturbative quantum chromodynamics.

Measurement of the Cross Section for e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+} and Observation of an Excited Ξ Baryon

Using a total of 11.0  fb^{-1} of e^{+}e^{-} collision data with center-of-mass energies between 4.009 and 4.6 GeV and collected with the BESIII detector at BEPCII, we measure fifteen exclusive cross sections and effective form factors for the process e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+} by means of a single baryon-tag method. After performing a fit to the dressed cross section of e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+}, no significant ψ(4230) or ψ(4260) resonance is observed in the Ξ^{-}Ξ[over ¯]^{+} final states, and upper limits at the 90% confidence level on Γ_{ee}B for the processes ψ(4230)/ψ(4260)→Ξ^{-}Ξ[over ¯]^{+} are determined. In addition, an excited Ξ baryon at 1820  MeV/c^{2} is observed with a statistical significance of 6.2-6.5σ by including the systematic uncertainty, and the mass and width are measured to be M=(1825.5±4.7±4.7)  MeV/c^{2} and Γ=(17.0±15.0±7.9)  MeV, which confirms the existence of the J^{P}=3/2^{-} state Ξ(1820).

[Overlapping Cervical Cell Image Segmentation Based on Bottleneck Detection and Watershed Algorithm]

This study proposes an image segmentation method based on bottleneck detection and watershed algorithm to solve the problem of overlapping cervical cell image. First, we use polygon approximation to get all feature points on the cell contour and then use bottleneck detection and ellipse fitting to obtain the correct split point pairs. Therefore, the approximate range of the overlapping region was determined. The watershed algorithm was used to obtain the internal boundary information for the gradient image of the region. Finally, the segmentation results of the overlapped cells were obtained by superimposing with the outer contour. The experimental results show that this algorithm can segment the contour of a single cell from the overlapping cervical cell images with good accuracy and integrity. The segmentation result is close to that of doctors' manual marking, and the segmentation result is better than other existing algorithms.

HIV-1 genotype is independently associated with immunodeficiency progression among Chinese men who have sex with men: an observational cohort study

OBJECTIVES

HIV-1 genetic diversity is increasing among men who have sex with men (MSM) in China, but the association of HIV-1 genotype with disease progression remains to be elucidated.

METHODS

We collected data in an observational longitudinal cohort study of 860 HIV-1-infected MSM in Guangzhou, China between January 2008 and March 2017. Kaplan-Meier analysis and Cox proportional hazard model were used to predict the time from HIV-1 diagnosis to immunodeficiency progression (CD4 cell count < 200 cells/μl) as well as adjusted hazard ratio (aHR).

RESULTS

CRF01_AE and HIV-1 subtype B infection were associated with higher percentage of patients progressed to immunodeficiency and higher incidence of immunodeficiency than infection with CRF07_BC or CRF55_01B. Compared with CRF07_BC, the time from HIV-1 diagnosis to immunodeficiency were different among the major HIV-1 genotypes, which ranked as follows, in descending order: CRF07_BC (7.03 years) > CRF55_01B (5.71 years, P = 0.014; aHR 3.752, P = 0.0923) > CRF01_AE (5.18 years, P < 0.001; aHR 4.733, P = 0.0152). HIV-1 genotype, viral load and baseline CD4 T-cell count were three independent variables associated with disease progression.

CONCLUSIONS

Our results confirm differential rates of immunodeficiency progression as a function of HIV-1 genotype. The impact of HIV-1 genotype on HIV epidemics, patient management and prevention should be further investigated.