[Analysis on the clinical features of sarcoid uveitis].

Objective: To analyze the clinical features of patients with sarcoid uveitis. Methods: This was a retrospective case series study. The medical records of 19 086 patients with uveitis admitted to the Department of Ophtalmology, The First Affiliated Hospital of Chongqing Medical University from April 2008 to December 2019 were collected. The general data, medical history, treatment, diagnosis, follow-up, ophthalmic and other auxiliary examinations were retrospectively analyzed. The paired sample Wilcoxon signed rank test was used to compare the best corrected visual acuity (BCVA) of the affected eye at the first visit to the BCVA of the affected eye at the corresponding last visit. Results: A total of 51 patients (97 eyes) with sarcoid uveitis were included, including 15 males (29.4%) and 36 females (70.6%), with a male/female ratio of 1/2.4. There were 46 patients (88 eyes) with presumed sarcoidosis and 5 patients (9 eyes) with definite sarcoidosis. The age of onset was 48 (40, 55) years and 90.2% of patients (46 cases) were involved in both eyes, while 88.2% of the patients (45 cases) were chronic, and only 11.8% (6 cases) showed acute inflammatory response. Anterior uveitis was the most common type (50.5%, 49 eyes). Ophthalmoscopy revealed retinal vasculitis in only 2 eyes (2.1%) and fundus fluorescence angiography (FFA) revealed diffuse vascular leakage of fluorescein in 64 eyes (66.0%). Thirty-one patients (59 eyes) were followed up for≥3 months. Cataract was the most common ocular complication, accounting for 44.1% (26 eyes), and the inflammatory response was controlled in 45 eyes (76.3%) treated with combination of corticosteroids and immunosuppressive agents. The patients were followed up for 21.5 (13.7, 29.3) months. Among 31 patients (59 eyes) followed up for≥3 months, BCVA was≥0.8 in 25 eyes (42.3%) and<0.3 in 15 eyes (25.4%) at the last follow-up, BCVA of 59 affected eyes of 31 patients was better than that at the first visit, the difference was statistically significant (Z=-2.76, P=0.006). Conclusions: Uveitis associated with sarcoidosis or presumed ocular sarcoidosis mainly manifests as a bilateral, chronic anterior uveitis with a subclinical retinal vasculitis. FFA shows subclinical retinal vasculitis in most patients. Glucocorticoid therapy in combination with other immunosuppressive agents can control inflammatory responses and improve visual acuity in most patients.

[Prevalence and transmission of pyrazinamide-resistant Mycobacterium tuberculosis in Hunan Province,China].

Objective: To provide a scientific reference for the prevention and treatment of pyrazinamide-resistant tuberculosis (PZA-R TB), we analyzed the prevalence and risk factors of pyrazinamide-resistant tuberculosis in Hunan province and described the genotyping and clustering characteristics of the pyrazinamide-resistant Mycobacterium tuberculosis (PZA-R MTB) isolates. Methods: The drug susceptibility test results of first-line anti-tuberculosis drugs including isoniazid (INH), rifampicin (RFP), streptomycin (SM), ethambutol (EMB) and pyrazinamide (PZA), and the characteristics of patients were collected from 3 862 tuberculosis patients in Hunan Chest Hospital (Institute of Tuberculosis Control and Prevention) from January 2016 to December 2018. The prevalence of PZA-R TB was calculated and risk factors were analyzed by univariate and multivariable logistic regression analysis. Two hundred and twelve Mycobacterium tuberculosis isolates selected from June 2017 to June 2018 were genotyped using the 24-loci MIRU-VNTR system. The genetic difference value (h), and the Hunter-Gaston index (HGI) were used to evaluate the resolution and variation for the 24 loci. MIRU-VNTR results were analyzed using BioNumerics 5.0 software to conduct cluster analysis. Clustered isolates were further analyzed by pncA gene sequencing. Results: The rate of PZA-R TB among tuberculosis patients and MDR patients was 14.7%(566/3 862) and 60.5%(511/844), respectively. Multivariable logistic regression analysis showed that patients who were INH mono-resistance and MDR had a higher risk of developing PZA resistance, compared with TB patients who were pan-sensitive to anti-TB drugs (INH, RFP, SM, and EMB). The adjusted OR value (95%CI) was 13.08(5.67-30.18), 298.41(164.88-540.08), respectively, and P values were all less than 0.01. Clustering analysis showed that 65 strains formed 19 clusters, the clustering rate was 30.7%(65/212). Of 19 clusters, eight clusters had at least two isolates with identical pncA mutation types within each cluster. In eight clusters, cluster 4, 6, 16 had four, three, and two patients who lived in the same county, respectively, thus providing probable epidemiological links for the recent transmission of PZA-R Mycobacterium tuberculosis. At least 47.6%(101/212) of PZA drug-resistant TB patients were suggestive of primary drug resistance caused by transmission. Conclusions: The prevalence of PZA-R TB was severe in Hunan province. PZA susceptibility testing should be performed for isolates resistant to any first-line anti-tuberculosis drugs, especially for MDR-MTB isolates. Nearly half of tuberculosis patients were suggestive of primary drug resistance caused by transmission. The prevention and treatment strategy of PZA-R TB should focus on the standardized treatment and management of patients as well as control of the source of infection.

[Comparative study of three scores in predicting the death risk of severe burn patients].

Objective: To explore the predictive values of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score on the death risk of severe burn patients. Methods: A retrospective case series study was conducted. From February 2018 to November 2019, 260 severe burn patients who met the inclusion criteria were admitted to the Department of Burns of the First Affiliated Hospital of Nanchang University, including 158 males and 102 females, aged 36 (3, 53) years. According to the final outcome, the patients were divided into survival group (n=229) and death group (n=31). Data of patients were compared and statistically analyzed with chi-square test or Mann-Whitney U test between the two groups, including the gender, age, cause of burn, site of burn, total burn area, depth of burn, combined inhalation injury, and combined underlying diseases on admission, and the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score calculated based on part of the aforementioned data. The Kendall tau-b coefficient method was used to analyze the consistency of the above-mentioned three scores in 260 severe burn patients. The receiver operating characteristic (ROC) curves of the above-mentioned three scores predicting the death risk of 260 severe burn patients were drawn, and the area under the curve (AUC), the optimal threshold, and the sensitivity and specificity under the optimal threshold were calculated. The quality of AUC of the above-mentioned three scores was compared by Delong test. Results: The gender, site of burn, and depth of burn of patients between the two groups were all similar (P>0.05). The age, total burn area, proportion of flame burn, proportion of combined inhalation injury, and proportion of combined underlying diseases of patients in death group were significantly higher than those in survival group (with Z values of 5.53 and 17.78, respectively, χ2 values of 16.23, 15.89, and 17.78, respectively, P<0.01); the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score of patients in death group were 142 (115, 155), 7 (5, 7), 2 (2, 3), all significantly higher than 64 (27, 87), 1 (0, 3), 0 (0, 1) in survival group (with Z values of 7.91, 7.64, and 7.61, respectively, P<0.01). In 260 severe burn patients, the results between the modified Baux score and Ryan score, modified Baux score and Belgian Outcome in Burn Injury score, Ryan score and Belgian Outcome in Burn Injury score were significantly consistent (with Kendall tau-b coefficients of 0.75, 0.71, and 0.86, respectively, P<0.01). The AUCs of ROC curves of the modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score for predicting the death risk of 260 severe burn patients were 0.92, 0.89, and 0.85, respectively (with 95% confidence intervals of 0.86-0.98, 0.83-0.95, and 0.78-0.93, respectively, P<0.01); the optimal thresholds were 106.5, 4.5, and 1.5 points, respectively; the sensitivity under the optimal threshold were 88.5%, 76.9%, and 73.1%, respectively, and the specificity under the optimal threshold were 88.5%, 87.2%, and 86.3%, respectively. The modified Baux score was similar to Belgian Outcome in Burn Injury score in the AUC quality (z=1.25, P>0.05), which were both significantly better than the AUC quality of Ryan score (with z values of 2.35 and 2.11, respectively, P<0.05). Conclusions: The modified Baux score, Belgian Outcome in Burn Injury score, and Ryan score have good ability in predicting the death risk of severe burn patients. From the perspective of clinical practice, the modified Baux score is more suitable as a predictive tool for the prognosis of severe burn patients.

Herders' perceptions of and responses to climate change in northern Pakistan.

Migratory pastoralism is an adaptation to a harsh and unstable environment, and pastoral herders have traditionally adapted to environmental and climatic change by building on their in-depth knowledge of this environment. In the Hindu Kush Himalayan region, and particularly in the arid and semiarid areas of northern Pakistan, pastoralism, the main livelihood, is vulnerable to climate change. Little detailed information is available about climate trends and impacts in remote mountain regions; herders' perceptions of climate change can provide the information needed by policy makers to address problems and make decisions on adaptive strategies in high pastoral areas. A survey was conducted in Gilgit-Baltistan province of Pakistan to assess herders' perceptions of, and adaptation strategies to climate change. Herders' perceptions were gathered in individual interviews and focus group discussions. The herders perceived a change in climate over the past 10-15 years with longer and more intense droughts in summer, more frequent and heavier snowfall in winter, and prolonged summers and relatively shorter winters. These perceptions were validated by published scientific evidence. The herders considered that the change in climate had directly impacted pastures and then livestock by changing vegetation composition and reducing forage yield. They had adopted some adaptive strategies in response to the change such as altering the migration pattern and diversifying livelihoods. The findings show that the herder communities have practical lessons and indigenous knowledge related to rangeland management and adaptation to climate change that should be shared with the scientific community and integrated into development planning.

Chloride-sensitive renal microangiopathy in the stroke-prone spontaneously hypertensive rat.

BACKGROUND: In the stroke-prone spontaneously hypertensive rat (SHRSP) fed a low-normal NaCl diet, we recently reported that supplemental KCl, but not KHCO(3) or K-citrate (KB/C), exacerbated hypertension and induced hyperreninemia and strokes. We now ask the following question: In these SHRSP, is either such selectively Cl(-)-sensitive hypertension or hyperreninemia a pathogenetic determinant of renal microvasculopathy? METHODS: SHRSPs were randomized to either supplemental KCl, KB/C, or nothing (control) at 10 weeks of age. Four and 14 weeks afterward, we assessed renal microangiopathy histologically and measured plasma renin activity (PRA). From randomization, blood pressure was measured radiotelemetrically and continually; proteinuria was measured periodically. RESULTS: KCl, but not KB/C, amplified renal microangiopathy and proteinuria. Four weeks after randomization, when KCl initially exacerbated hypertension, renal microangiopathy, hyperproteinuria, and hyperreninemia had not yet occurred. However, across all groups, the increment of SBP at four weeks strongly predicted its final increment, severity of renal microangiopathy, proteinuria, and PRA 14 weeks after randomization. Then, the severity of renal microangiopathy varied directly with the levels of systolic blood pressure (SBP; R(2) = 0.9, P < 0.0001), PRA (R(2) = 0.7, P < 0.0001), and proteinuria (R(2) = 0.8, P < 0.0001) as continuous functions across all treatment groups. Renal creatinine clearance was greater with KB/C. CONCLUSIONS: In the SHRSP, (1) like cerebral microangiopathy, renal microangiopathy is selectively Cl(-) sensitive and hence, systemic microangiopathy is as well; (2) Cl(-) likely amplifies microangiopathy by exacerbating hypertension and possibly also by increasing PRA; and (3) Cl(-) might increase blood pressure and PRA by further constricting the renal afferent arteriole.

Reduced dietary potassium reversibly enhances vasopressor response to stress in African Americans.

Acute vasopressor responses to stress are adrenergically mediated and hence potentially subject to differential modulation by dietary potassium and sodium. The greater vasopressor responsiveness in blacks compared with whites might then be consequent not only to a high dietary salt intake but also to a marginally reduced dietary potassium intake. Under controlled metabolic conditions, we compared acute vasopressor responses to cold and mental stress in black and white normotensive men during three successive dietary periods: (1) while dietary potassium was reduced (30 mmol K+/70 kg per day) and salt was restricted (10 to 14 days); (2) while salt was loaded (15 to 250 mmol Na+/70 kg per day) (7 days); and (3) while salt loading was continued and potassium was either supplemented (70 mmol K+/70 kg per day) (7 to 21 days) in 9 blacks and 6 whites or continued reduced (30 mmol K+/70 kg per day) (28 days) in 4 blacks (time controls). At the lower potassium intake, cold-induced increase in forearm vascular resistance in blacks was twice that in whites during both salt restriction and salt loading. Normalization of dietary potassium attenuated cold-induced increases in both forearm vascular resistance and systolic and diastolic blood pressures in blacks but only in systolic pressure in whites. In blacks but not in whites, normalization of dietary potassium attenuated mental stress-induced increases in systolic and diastolic pressures. In normotensive blacks but not whites, a marginally reduced dietary intake of potassium reversibly enhances adrenergically mediated vasopressor responsiveness to stress. That responsiveness so enhanced over time might contribute to the pathogenesis of hypertension in blacks.

Genetically determined chloride-sensitive hypertension and stroke.

The stroke-prone spontaneously hypertensive rat (SHRSP) is a genetically determined model of "salt-sensitive" stroke and hypertension whose full phenotypic expression is said to require a diet high in Na+ and low in K+. We tested the hypothesis that dietary Cl- determines the phenotypic expression of the SHRSP. In the SHRSP fed a normal NaCl diet, supplementing dietary K+ with KCl exacerbated hypertension, whereas supplementing either KHCO3 or potassium citrate (KB/C) attenuated hypertension, when blood pressure (BP) was measured radiotelemetrically, directly and continually. Supplemental KCl, but not KB/C, induced strokes, which occurred in all and only those rats in the highest quartiles of both BP and plasma renin activity (PRA). PRA was higher with KCl than with KB/C. These observations demonstrate that with respect to both severity of hypertension and frequency of stroke the phenotypic expression of the SHRSP is (i) either increased or decreased, depending on whether the anionic component of the potassium salt supplemented is, or is not, Cl-; (ii) increased by supplementing Cl- without supplementing Na+, and despite supplementing K+; and hence (iii) both selectively Cl--sensitive and Cl--determined. The observations suggest that in the SHRSP selectively supplemented with Cl- the likelihood of stroke depends on the extent to which both BP and PRA increase.