1.Indoor Particulate Matter Concentration in Households of Darkhan City
Nyamdorj J ; Bolor M ; Maralmaa E ; Yerkyebulan M ; Ser-Od Kh ; Myagmarchuluun S ; Shatar Sh ; Gantuya D ; Gregory C. Gray ; Junfeng Zhang ; Ulziimaa D ; Damdindorj B ; Khurelbaatar N ; Davaalkham D
Mongolian Journal of Health Sciences 2025;85(1):25-29
Background:
A 2018 study on the global burden of disease, accidents, and risk factors reported that 1.6 million peo
ple died in 2017 due to household air pollution. Poor indoor air quality has been highlighted as a contributing factor to
respiratory diseases, cardiovascular conditions, and exacerbation of asthma and allergies. A 2019 study estimated that
long-term exposure to fine particulate matter (PM2.5) with a diameter of 2.5 micrometers or less reduces average life
expectancy by 1.8 years, with more severe effects in highly polluted regions. Additionally, a study by Miller et al. (2007)
found that prolonged exposure to PM2.5 increases the risk of cardiovascular diseases, particularly among women. Direct
measurement devices are highly effective in determining indoor PM2.5 concentrations, identifying sources of pollution,
tracking pollutant dispersion, and monitoring temporal variations. Studies suggest that direct measurement is an accurate,
cost-effective method that provides detailed data suitable for local conditions.
Aim:
To investigate the indoor air quality of houses and apartments in Darkhan city during the winter season using the
Purple Air monitoring device.
Materials and Methods:
A cross-sectional study was conducted with a targeted sample of 128 households in Darkhan
city. The study examined factors such as stove type, type of coal used, annual and daily coal consumption, frequency of
heating, and chimney sealing conditions. To collect data, the Purple Air monitoring device was installed in each house
hold for a month, after which it was retrieved. During retrieval, participants completed a questionnaire. The questionnaire
consisted of 55 questions across 7 pages at the time of device installation and 25 questions across 3 pages at the time of
device retrieval. The collected data was analyzed using SPSS 25.0.
Results:
A total of 128 households in Darkhan city participated in the study. The average duration of residence in the
current home was 9.5 years, with no statistically significant variation. The distribution of housing types was as follows:
traditional Mongolian gers (40.6%), houses (39.1%), and apartments (20.3%). The 24-hour average PM2.5 concentration
was highest in gers (70.9 μg/m³), followed by houses (46.8 μg/m³) and apartments (22.8 μg/m³), with a statistically significant difference (p=0.0001). PM2.5 levels were most variable in gers, followed by houses and then apartments. House
holds using central heating (apartments) had an average 24-hour PM2.5 concentration of 22.8 μg/m³, whereas households
using stoves (gers and houses) had a significantly higher concentration of 59.4 μg/m³ (p=0.0001). However, there was
no statistically significant difference between traditional and improved stoves. Among study participants, 21.4% reported
that someone in their household smoked indoors. Additionally, 86.5% regularly burned incense, candles, or herbs, while
99.2% did not use an air purifier.
Conclusion
The indoor particulate matter concentration in houses and gers in Darkhan was 59.4μг/m3. Variations in
stove types, poor chimney sealing limited space, and frequent gaps and cracks contribute to increased spread of indoor
air pollutants.
2.Comparative analysis of household indoor PM2.5 concentrations and prevalence of hypertension between cities
Anujin M ; Myagmarchuluun S ; Erkebulan M ; Ser-Od Kh ; Shatar Sh ; Gantuyаa D ; Enkhjargal G ; Munkh-Erdene L ; Gregory C. Gray ; Jungfeng Zhang ; Damdindorj B ; Ulziimaa D ; Davaalkham D
Mongolian Journal of Health Sciences 2025;89(5):5-10
Background:
According to the World Health Organization (WHO), 6.7 million people die annually due to air pollution
caused by solid fuel use, with the majority of deaths resulting from respiratory diseases and cardiovascular conditions. In
Mongolia, air pollution ranks as the fourth leading risk factor contributing to mortality, following hypertension, diabetes,
and other major health risks. Although there have been numerous studies on outdoor air pollution in Mongolia, research
linking indoor air pollution at the household level with the health status of residents remains limited.
Aim:
To compare indoor PM2.5 concentrations in households of Ulaanbaatar and Darkhan and examine their association
with hypertension during the winter season.
Materials and Methods:
The study was conducted during November and December 2023, and January 2024, involving
240 households in Ulaanbaatar and Darkhan. Indoor PM2.5 concentrations were measured using Purple Air real-time
sensors continuously for 24 hours over approximately one month. After measuring indoor air pollution, individuals aged
18–60 years living in the selected households were recruited based on specific inclusion criteria. Blood pressure was
measured three times and the average value was recorded. Information on respiratory illnesses was collected through
structured questionnaires. Statistical analysis was performed using STATA version 19.0.
Results:
A total of 241 households participated in the study, with 116 from Ulaanbaatar and 125 from Darkhan. Of the
participants, 46.5% were male and 53.5% were female. In terms of housing type, 96 households (39.8%) lived in gers,
97 (40.2%) lived in stove-heated houses, and 48 (19.9%) lived in apartments. Among all participants, 66.0% (n=159) had
hypertension and 34.0% (n=79) had normal blood pressure. Among participants aged over 40, 69.9–88.5% had hypertension, which is statistically significantly higher compared to younger individuals (p=0.0001). By body mass index, 75.3%
(n=72) of overweight individuals and 78.4% (n=58) of obese participants had hypertension, showing a statistically significant difference compared to participants with normal weight (p=0.0001). The 24-hour average concentration of indoor
PM2.5 was measured using the Purple Air device, and the levels in gers and stove-heated houses exceeded the limit set
by the MNS 4585:2025 standard (37.5 µg/m³)
Conclusion
This study identified a relationship between environmental factors, such as air pollution and housing type,
and the prevalence of hypertension. The indoor PM2.5 concentration in gers and stove-heated houses was above the standard limit, indicating a negative impact on the health of those residents. Furthermore, the high prevalence of hypertension
among participants over the age of 40 and those who are overweight suggests a possible link to lifestyle and environmental conditions.
3.Comparative Analysis of Outdoor Particulate Matter Concentrations in Ulaanbaatar Using Direct Measurements and Fixed Monitoring Station Data
Ulziikhutag B ; Enkhjargal G ; Buyantushig B ; Nyamsuren B ; Shatar Sh ; Gantuya D ; Myagmarchuluun S ; Gregory Gray ; Junfeng Zhang ; Ulziimaa D ; Damdindorj B ; Davaalkham D
Mongolian Journal of Health Sciences 2025;89(5):112-117
Backgroun:
Air pollution is a major global public health concern that poses serious risks to human health regardless of
a country’s level of economic or technological development. According to the World Health Organization (WHO, 2021),
nine out of ten people worldwide breathe polluted air, and air pollution is responsible for the deaths of approximately
800 people every hour and 13 people every minute. Prolonged exposure to polluted air has been linked to a wide range
of chronic illnesses, including chronic obstructive pulmonary disease (COPD), lung and bronchial cancers, asthma, and
stroke. In Mongolia, air pollution reaches its highest levels during the winter months, particularly in Ulaanbaatar, where
the majority of the country’s population resides. A study conducted by Enkhjargal G. (2012) reported that the concentrations
of PM10 and PM2.5 in Ulaanbaatar were 7–8 times higher than the WHO recommended guidelines. In response
to such challenges, many countries have increasingly adopted low-cost, direct measurement devices such as PurpleAir
to monitor air quality. These devices are valued for their accessibility, network connectivity, and potential role in smart
city pollution management systems. Despite their global application, there remains a lack of research in Mongolia on the
use of PurpleAir sensors to measure PM2.5 concentrations and compare the results with official monitoring station data.
Addressing this gap is essential for improving local air quality monitoring capacity and informing effective public health
and environmental policies.
Aim:
Determination of PM2.5 particulate matter pollution in the outdoor environment of Ulaanbaatar city using a direct
measurement device (Purple Air).
Materials and Methods:
A cross-sectional study design was employed. Direct measurement devices (Purple Air) were
installed in selected districts of central Ulaanbaatar between December 2024 and February 2025, measuring PM2.5 concentrations
at two-minute intervals over 24-hour periods. All data were statistically processed and analyzed using the
SPSS-26 software package.
Results:
The average concentration of PM2.5 particles in the air of Ulaanbaatar city in winter is 66.68 μg/m3. Compared
to the districts, the highest concentration was determined in SKHD (118.58±90.22 μg/m3), while the lowest concentration
was determined in KHUD (42.37±43.51 μg/m3). Compared to the days of the week, the highest concentrations were measured
on Monday (76.68±71.98 μg/m³), Saturday (77.50±71.63 μg/m³), and Sunday (80.34±74.45 μg/m³). The highest
concentration of PM2.5 particles occurred from 6 pm to 1 am, and the lowest concentration was measured during the day
(between 2 pm and 4 pm). The highest concentration of PM2.5 was measured in December (74.22±73.45 μg/m3), while
the lowest concentration was measured in February (50.25±57.44 μg/m3).
Conclusion
The concentration of PM2.5 in the air of Ulaanbaatar city is 1.7 times higher than the general standard and
technical requirements of Mongolia in winter, and the highest concentration is in the SKHD. The highest concentration of
PM2.5 occurs more often in December and at night than in the winter months.
4.Comparative Analysis of Outdoor Particulate Matter Concentrations in Ulaanbaatar Using Direct Measurements and Fixed Monitoring Station Data
Maralmaa E ; ; Yerkyebulan M ; Ser-Od Kh ; Shatar Sh ; Gantuya D ; Munkh-Erdene L ; Enkhjargal G ; Myagmarchuluun S ; Gregory Gray ; Junfeng Zhang ; Ulziimaa D ; Damdindorj B ; Davaalkham D ; ; Darambazar G
Mongolian Journal of Health Sciences 2025;89(5):105-111
Background:
Particulate matter with an aerodynamic diameter of 2.5 micrometers or smaller (PM2.5) penetrates
deep into the alveoli through the respiratory tract and is characterized by its ability to induce oxidative stress, systemic
inflammation, and vascular inflammation. Mongolia ranks among the countries with the highest levels of air pollution. In
Ulaanbaatar, where more than half of the country’s population resides, wintertime PM2.5 concentrations often exceed 200
μg/m³, which is about eight times higher than the World Health Organization (WHO) guideline value. A study involving
1,200 adults in Ulaanbaatar showed that quality of life deteriorated sharply during periods of high air pollution, with
effects more pronounced among individuals who already had impaired respiratory function.
Aim:
To examine the relationship between indoor household PM2.5 concentrations and lung function indicators among
adults in Ulaanbaatar and Darkhan.
Materials and Methods:
This analytical cross-sectional study recruited adult participants from Ulaanbaatar and Darkhan
through targeted sampling. Household air quality was measured using PurpleAir sensors, which were installed in
participants’ homes for one month. After exposure measurement, lung function was assessed via spirometry. Statistical
analyses were conducted using SPSS version 25.0.
Results:
A total of 236 participants were included: 114 (48.3%) from Ulaanbaatar and 122 (51.7%) from Darkhan. The
sample consisted of 111 men (47.0%) and 125 women (53.0%). The mean indoor PM2.5 concentration was 66.24 μg/m³
(SD 44.87 μg/m³), ranging from a minimum of 7.79 μg/m³ to a maximum of 264.55 μg/m³. Stratification by housing type
showed the highest PM2.5 levels in gers (82.34 μg/m³), followed by detached houses (67.34 μg/m³), while apartments
had the lowest concentrations (32.24 μg/m³). Correlation analysis revealed statistically significant negative associations
between PM2.5 levels and measures of expiratory function, including the FEV1/FVC ratio, peak expiratory flow (PEF),
and mid-expiratory flow (FEF25–75). Reduced forced vital capacity (FVC) was observed in 9.4% of participants, reduced
forced expiratory volume in one second (FEV1) in 15.3%, and a decreased FEV1/FVC ratio in 3.8%.
Conclusion
Indoor household PM2.5 concentrations were highest in gers, and expiratory flow-related lung function
parameters showed significant negative associations with particulate exposure. This suggests that indoor PM2.5 primarily
affects airflow limitation rather than overall lung volumes in this population.
5.2021 Asian Pacific Society of Cardiology Consensus Recommendations on the use of P2Y12 receptor antagonists in the Asia-Pacific Region: Special populations.
W E I C H I E H T A N TAN ; P C H E W CHEW ; L A M T S U I TSUI ; T A N TAN ; D U P L Y A K O V DUPLYAKOV ; H A M M O U D E H HAMMOUDEH ; Bo ZHANG ; Yi LI ; Kai XU ; J O N G ONG ; Doni FIRMAN ; G A M R A GAMRA ; A L M A H M E E D ALMAHMEED ; D A L A L DALAL ; T A N TAN ; S T E G STEG ; N N G U Y E N NGUYEN ; A K O AKO ; A L S U W A I D I SUWAIDI ; C H A N CHAN ; S O B H Y SOBHY ; S H E H A B SHEHAB ; B U D D H A R I BUDDHARI ; Zu Lv WANG ; Y E A N Y I P F O N G FONG ; K A R A D A G KARADAG ; K I M KIM ; B A B E R BABER ; T A N G C H I N CHIN ; Ya Ling HAN
Chinese Journal of Cardiology 2023;51(1):19-31
6.Hepatocyte apoptosis fragment product cytokeratin-18 M30 level and non-alcoholic steatohepatitis risk diagnosis: an international registry study.
Huai ZHANG ; Rafael S RIOS ; Jerome BOURSIER ; Rodolphe ANTY ; Wah-Kheong CHAN ; Jacob GEORGE ; Yusuf YILMAZ ; Vincent Wai-Sun WONG ; Jiangao FAN ; Jean-François DUFOUR ; George PAPATHEODORIDIS ; Li CHEN ; Jörn M SCHATTENBERG ; Junping SHI ; Liang XU ; Grace Lai-Hung WONG ; Naomi F LANGE ; Margarita PAPATHEODORIDI ; Yuqiang MI ; Yujie ZHOU ; Christopher D BYRNE ; Giovanni TARGHER ; Gong FENG ; Minghua ZHENG
Chinese Medical Journal 2023;136(3):341-350
BACKGROUND:
Liver biopsy for the diagnosis of non-alcoholic steatohepatitis (NASH) is limited by its inherent invasiveness and possible sampling errors. Some studies have shown that cytokeratin-18 (CK-18) concentrations may be useful in diagnosing NASH, but results across studies have been inconsistent. We aimed to identify the utility of CK-18 M30 concentrations as an alternative to liver biopsy for non-invasive identification of NASH.
METHODS:
Individual data were collected from 14 registry centers on patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD), and in all patients, circulating CK-18 M30 levels were measured. Individuals with a NAFLD activity score (NAS) ≥5 with a score of ≥1 for each of steatosis, ballooning, and lobular inflammation were diagnosed as having definite NASH; individuals with a NAS ≤2 and no fibrosis were diagnosed as having non-alcoholic fatty liver (NAFL).
RESULTS:
A total of 2571 participants were screened, and 1008 (153 with NAFL and 855 with NASH) were finally enrolled. Median CK-18 M30 levels were higher in patients with NASH than in those with NAFL (mean difference 177 U/L; standardized mean difference [SMD]: 0.87 [0.69-1.04]). There was an interaction between CK-18 M30 levels and serum alanine aminotransferase, body mass index (BMI), and hypertension ( P < 0.001, P = 0.026 and P = 0.049, respectively). CK-18 M30 levels were positively associated with histological NAS in most centers. The area under the receiver operating characteristics (AUROC) for NASH was 0.750 (95% confidence intervals: 0.714-0.787), and CK-18 M30 at Youden's index maximum was 275.7 U/L. Both sensitivity (55% [52%-59%]) and positive predictive value (59%) were not ideal.
CONCLUSION
This large multicenter registry study shows that CK-18 M30 measurement in isolation is of limited value for non-invasively diagnosing NASH.
Humans
;
Non-alcoholic Fatty Liver Disease/diagnosis*
;
Keratin-18
;
Biomarkers
;
Biopsy
;
Hepatocytes/pathology*
;
Apoptosis
;
Liver/pathology*
7.Nodal T-follicular helper cell lymphoma, angioimmunoblastic-type associated with diffuse large B-cell lymphoma: a clinicopathological study.
G N WANG ; W G ZHAO ; D D ZHANG ; Y P ZHANG ; E J LIU ; S S LU ; W C LI
Chinese Journal of Pathology 2023;52(9):918-923
Objective: To investigate the clinicopathological features and molecular genetics of diffuse large B-cell lymphomas (DLBCL) with concurrent or secondary to nodal T-follicular helper cell lymphoma, angioimmunoblastic-type (nTFHL-AI). Methods: The clinicopathological features and molecular genetics of DLBCL associated with nTFHL-AI diagnosed between January 2015 and October 2022 at the First Affiliated Hospital of Zhengzhou University were analyzed using histology, immunohistochemistry, PCR, EBV-encoded RNA in situ hybridization and fluorescence in situ hybridization (FISH). Clinical information was collected and analyzed. Results: A total of 6 cases including 3 nTFHL-AI with secondary DLBCL and 3 composite lymphomas were reviewed. There were 4 male and 2 female patients, whose ages ranged from 40 to 74 years (median 57 years). All patients presented with nodal lesions at an advanced Ann Arbor stage Ⅲ/Ⅳ (6/6). Bone marrow involvement was detected in 4 patients. All cases showed typical histologic and immunophenotypic characteristics of nTFHL-AI. Among them, 5 cases of DLBCL with concurrent nTFHL-AI exhibited numerous large atypical lymphoid cells and the tumor cells were CD20 and CD79α positive. The only case of DLBCL secondary to nTFHL-AI showed plasma cell differentiation and reduced expression of CD20. All of cases were activated B-cell (ABC)/non-germinal center B-cell (non-GCB) subtype. Three of the 6 cases were EBV positive with>100 positive cells/high power field, meeting the diagnostic criteria of EBV+DLBCL. The expression of MYC and CD30 protein in the DLBCL region was higher than that in the nTFHL-AI region (n=5). C-MYC, bcl-6 and bcl-2 translocations were not detected in the 4 cases that were subject to FISH. Four of the 6 patients received chemotherapy after diagnosis. For the DLBCL cases of nTFHL-AI with secondary DLBCL, the interval was between 2-20 months. During the follow-up period ranging from 3-29 months, 3 of the 6 patients died of the disease. Conclusions: DLBCL associated with nTFHL-AI is very rare. The expansion of EBV-infected B cells in nTFHL-AI may progress to secondary EBV+DLBCL. However, EBV-negative cases have also been reported, suggesting possible other mechanisms. The up-regulation of MYC expression in these cases suggests a possible role in B-cell lymphomagenesis. Clinicians should be aware that another biopsy is still necessary to rule out concurrent or secondary DLBCL when nodal and extranodal lesions are noted after nTFHL-AI treatment.
Female
;
Male
;
Humans
;
In Situ Hybridization, Fluorescence
;
Lymphoma, Large B-Cell, Diffuse
;
B-Lymphocytes
;
Biopsy
;
T-Lymphocytes, Helper-Inducer
8.A medium- and long-term comparative observation on volumetric changes of cervical disc herniation after symmetrically or asymmetrically decompression and conservative treatment for cervical spondylotic myelopathy.
A D ZHU ; C L ZHANG ; X YAN ; S FU ; D Z LI ; C DONG ; Y K WANG
Chinese Journal of Surgery 2023;61(8):666-674
Objective: To compare the volumetric changes of cervical disc herniation (CDH) after cervical microendoscopic laminoplasty(CMEL),expansive open-door laminoplasty (EOLP) and conservative treatment. Methods: A retrospective study was conducted involving 101 patients with cervical spondylotic myelopathy(CSM),at the Department of Orthopaedic Surgery,the First Affiliated Hospital of Zhengzhou University from April 2012 to April 2021. The patients included 52 males and 49 females with an age of (54.7±11.8) years(range:25 to 86 years). Among them, 35 patients accepted CMEL treatment,33 patients accepted EOLP treatment,while 33 patients accepted conservative treatment. Volume data of CDH were measured by three-dimensional analysis of the initial and follow-up MRI images. The absorption rate and reprotrusion rate of CDH were calculated. The happening of resorption or reprotrusion was defined when the ratio was greater than 5%. The clinical outcomes and quality of life were evaluated by the Japanese Orthopaedic Association (JOA) score and the neck disability index (NDI).Quantitative data was analyzed by one-way ANOVA with post LSD-t test (multiple comparison) or Kruskal-Wallis test. Categorical data was analyzed by χ2 test. Results: The follow-up time of the CMEL group,EOLP group and the conservative treatment group were (27.6±18.8)months,(21.6±6.9)months and(24.9±16.3)months respectively with no significant difference(P>0.05). Changes of CDH volume in patients:(1) There were 96 CDH of 35 patients in the CMEL group,among which 78 showed absorption. The absorption frequency was 81.3%(78/96) and the absorption rate was ranged 5.9% to 90.9%;9 CDH showed reprotrusion,the reprotrusion frequency was 9.4% (9/96) and the reprotrusion rate was 5.9% to 13.3%;(2) There were 94 CDH of 33 patients in the EOLP group,of which 45 showed absorption. The absorption prevalence was 47.9% (45/94) and the absorption rate was 5.0% to 26.7%;20 CDH showed reprotruded,with the reprotrusion frequency of 21.3% (20/94) and the reprotrusion rate was 5.8% to 28.3%;(3) There were 102 CDH in 33 patients of the conservative group. Among them, 5 showed absorption. The absorption frequency was 4.9% (5/102),and the absorption rate was 7.2% to 14.3%;58 CDH showed reprotruded with the re-protrusion ratio of 56.9% (58/102) and the re-protrusion rate was 5.4% to 174.1%. The absorption ratio and reprotrusion ratio of the CMEL group were statistically different from EOLP group or the conservative group (P<0.01).The absorption ratio and reprotrusion ratio of the EOLP group was different from conservative group (all P<0.01). In terms of clinical outcomes, the excellent/good rate of the JOA score and NDI scores in the CMEL group were different from that of conservative group (all P<0.01) but not from that of the EOLP group(P>0.05). Conclusions: CMEL is an effective method for the treatment of CSM,making CDH easier to resorption compared to the EOLP or conservative treatment,thus making a better decompression effect on the nerves. This study enlightened on a new strategy for the clinical treatment of CSM.
Male
;
Female
;
Humans
;
Adult
;
Middle Aged
;
Aged
;
Aged, 80 and over
;
Retrospective Studies
;
Intervertebral Disc Displacement/surgery*
;
Conservative Treatment
;
Quality of Life
;
Treatment Outcome
;
Spondylosis/surgery*
;
Cervical Vertebrae/surgery*
;
Spinal Cord Diseases
;
Laminoplasty/methods*
;
Decompression
9.Development and validation of a prognostic prediction model for patients with stage Ⅰ to Ⅲ colon cancer incorporating high-risk pathological features.
K X LI ; Q B WU ; F Q ZHAO ; J L ZHANG ; S L LUO ; S D HU ; B WU ; H L LI ; G L LIN ; H Z QIU ; J Y LU ; L XU ; Z WANG ; X H DU ; L KANG ; X WANG ; Z Q WANG ; Q LIU ; Y XIAO
Chinese Journal of Surgery 2023;61(9):753-759
Objective: To examine a predictive model that incorporating high risk pathological factors for the prognosis of stage Ⅰ to Ⅲ colon cancer. Methods: This study retrospectively collected clinicopathological information and survival outcomes of stage Ⅰ~Ⅲ colon cancer patients who underwent curative surgery in 7 tertiary hospitals in China from January 1, 2016 to December 31, 2017. A total of 1 650 patients were enrolled, aged (M(IQR)) 62 (18) years (range: 14 to 100). There were 963 males and 687 females. The median follow-up period was 51 months. The Cox proportional hazardous regression model was utilized to select high-risk pathological factors, establish the nomogram and scoring system. The Bootstrap resampling method was utilized for internal validation of the model, the concordance index (C-index) was used to assess discrimination and calibration curves were presented to assess model calibration. The Kaplan-Meier method was used to plot survival curves after risk grouping, and Cox regression was used to compare disease-free survival between subgroups. Results: Age (HR=1.020, 95%CI: 1.008 to 1.033, P=0.001), T stage (T3:HR=1.995,95%CI:1.062 to 3.750,P=0.032;T4:HR=4.196, 95%CI: 2.188 to 8.045, P<0.01), N stage (N1: HR=1.834, 95%CI: 1.307 to 2.574, P<0.01; N2: HR=3.970, 95%CI: 2.724 to 5.787, P<0.01) and number of lymph nodes examined (≥36: HR=0.438, 95%CI: 0.242 to 0.790, P=0.006) were independently associated with disease-free survival. The C-index of the scoring model (model 1) based on age, T stage, N stage, and dichotomous variables of the lymph nodes examined (<12 and ≥12) was 0.723, and the C-index of the scoring model (model 2) based on age, T stage, N stage, and multi-categorical variables of the lymph nodes examined (<12, 12 to <24, 24 to <36, and ≥36) was 0.726. A scoring system was established based on age, T stage, N stage, and multi-categorical variables of lymph nodes examined, the 3-year DFS of the low-risk (≤1), middle-risk (2 to 4) and high-risk (≥5) group were 96.3% (n=711), 89.0% (n=626) and 71.4% (n=313), respectively. Statistically significant difference was observed among groups (P<0.01). Conclusions: The number of lymph nodes examined was an independent prognostic factor for disease-free survival after curative surgery in patients with stage Ⅰ to Ⅲ colon cancer. Incorporating the number of lymph nodes examined as a multi-categorical variable into the T and N staging system could improve prognostic predictive validity.
Male
;
Female
;
Humans
;
Prognosis
;
Neoplasm Staging
;
Retrospective Studies
;
Nomograms
;
Lymph Nodes/pathology*
;
Risk Factors
;
Colonic Neoplasms/surgery*
10.Impact of COVID-19 pandemic on the management of imported malaria in China.
Y LIU ; D WANG ; Z HE ; T ZHANG ; H YAN ; W LIN ; X ZHANG ; S LU ; Y LIU ; D WANG ; J LI ; W RUAN ; S LI ; H ZHANG
Chinese Journal of Schistosomiasis Control 2023;35(4):383-388
OBJECTIVE:
To examine the impact of COVID-19 pandemic on the epidemic status of imported malaria and national malaria control program in China, so as to provide insights into post-elimination malaria surveillance.
METHODS:
All data pertaining to imported malaria cases were collected from Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region during the period from January 1, 2018 through December 31, 2021. The number of malaria cases, species of malaria parasites, country where malaria parasite were infected, diagnosis and treatment after returning to China, and response were compared before (from January 1, 2018 to January 22, 2020) and after the COVID-19 pandemic (from January 23, 2020 to December 31, 2021).
RESULTS:
A total of 2 054 imported malaria cases were reported in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region during the period from January 1, 2018 to December 31, 2021, and there were 1 722 cases and 332 cases reported before and after the COVID-19 pandemic, respectively. All cases were reported within one day after definitive diagnosis. The annual mean number of reported malaria cases reduced by 79.30% in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region after the COVID-19 pandemic (171 cases) than before the pandemic (826 cases), and the number of monthly reported malaria cases significantly reduced in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region since February 2020. There was a significant difference in the constituent ratio of species of malaria parasites among the imported malaria cases in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region before and after the COVID-19 pandemic (χ2 = 146.70, P < 0.05), and P. falciparum malaria was predominant before the COVID-19 pandemic (72.30%), while P. ovale malaria (44.28%) was predominant after the COVID-19 pandemic, followed by P. falciparum malaria (37.65%). There was a significant difference in the constituent ratio of country where malaria parasites were infected among imported malaria cases in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region before and after the COVID-19 pandemic (χ2 = 13.83, P < 0.05), and the proportion of malaria cases that acquired Plasmodium infections in western Africa reduced after the COVID-19 pandemic that before the pandemic (44.13% vs. 37.95%; χ2 = 4.34, P < 0.05), while the proportion of malaria cases that acquired Plasmodium infections in eastern Africa increased after the COVID-19 pandemic that before the pandemic (9.58% vs. 15.36%; χ2 = 9.88, P = 0.02). The proportion of completing case investigation within 3 days was significantly lower after the COVID-19 pandemic than before the pandemic (96.69% vs. 98.32%; χ2= 3.87, P < 0.05), while the proportion of finishing foci investigation and response within 7 days was significantly higher after the COVID-19 pandemic than before the pandemic (100.00% vs. 98.43%; χ2 = 3.95, P < 0.05).
CONCLUSIONS
The number of imported malaria cases remarkably reduced in Anhui Province, Hubei Province, Henan Province, Zhejiang Province and Guangxi Zhuang Autonomous Region of China during the COVID-19 pandemic, with a decreased proportion of completing case investigations within 3 days. The sensitivity of the malaria surveillance-response system requires to be improved to prevent the risk of secondary transmission of malaria due to the sharp increase in the number of imported malaria cases following the change of the COVID-19 containment policy.
Humans
;
Pandemics
;
China/epidemiology*
;
Incidence
;
COVID-19/epidemiology*
;
Malaria/prevention & control*
;
Malaria, Falciparum/epidemiology*

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