Niche convergence and biogeographic history shape elevational tree community assembly in a subtropical mountain forest.

Niche convergence or conservatism have been proposed as essential mechanisms underlying elevational plant community assembly in tropical mountain ecosystems. Subtropical mountains, compared to tropical mountains, are likely to be shaped by a mixing of different geographic affinities of species and remain somehow unclear. Here, we used 31 0.1-ha permanent plots distributed in subtropical forests on the eastern and western aspects of the Gaoligong Mountains, southwest China between 1498 m and 3204 m a.sl. to evaluate how niche-based and biogeographic processes shape tree community assembly along elevational gradients. We analyzed the elevational patterns of taxonomic, phylogenetic and functional diversity, as well as of individual traits, and assessed the relative importance of environmental effects on these diversity measures. We then classified tree species as being either tropical affiliated or temperate affiliated and estimated their contribution to the composition of biogeographic affinities. Species richness decreased with elevation, and species composition showed apparent turnover across the aspects and elevations. Most traits exhibited convergent patterns across the entire elevational gradient. Phylogenetic and functional diversity showed opposing patterns, with phylogenetic diversity increasing and functional diversity decreasing with elevation. Soil nutrients, especially phosphorus and nitrogen, appeared to be the main abiotic variables driving the elevational diversity patterns. Communities at lower elevations were occupied by tropical genera, while highlands contained species of tropical and temperate biogeographic affinities. Moreover, the high phylogenetic diversity at high elevations were likely due to differences in evolutionary history between temperate and tropical species. Our results highlight the importance of niche convergence of tropical species and the legacy of biogeographic history on the composition and structure of subtropical mountain forests. Furthermore, limited soil phosphorus caused traits divergence and the partitioning for different forms of phosphorus may explain the high biodiversity found in phosphorus-limited subtropical forests.

Clinical Features of Spontaneous Remission in the Classic Fever of Unknown Origin: A Retrospective Study.

Objective To summarize the clinical features of spontaneous remission in classic fever of unknown origin (FUO). Methods Medical records of 121 patients diagnosed with FUO at admission in Peking Union Medical College Hospital between January 2018 and June 2018 were reviewed retrospectively. Patients who were discharged without etiological diagnoses were followed for 2 years. The clinical features and outcomes of these patients were summarized. Multivariate logistic regression was used to analyze related factors of spontaneous remission of FUO. Results After excluding 2 patients who lost to follow-up, the etiology of 119 FUO patients were as follows: infectious diseases in 30 (25.2%) cases, connective tissue diseases in 28 (23.5%) cases, tumor diseases in 8 (6.7%) cases, other diseases in 6 (5.0%) cases, and unknown diagnoses in 47 (39.5%) cases. Totally, 41 patients experienced spontaneous remission of fever (the median time from onset to remission was 9 weeks, ranging from 4 to 39 weeks). In patients with spontaneous remission in FUO, lymphadenopathy was less common clinical manifestation, the levels of inflammatory markers including leukocyte count, neutrophil count, neutrophil ratio, C-reactive protein, and ferritin were lower, and the proportion of CD8 positive T lymphocytes expressing CD38 was lower. Multivariate logistic regression analysis of factors with a P-value < 0.05 in univariate analysis shown that white blood cell count (OR: 0.545, 95%CI: 0.306-0.971, P = 0.039), neutrophil count (OR: 2.074, 95%CI: 1.004-4.284, P = 0.049), and proportion of neutrophils (OR: 0.928, 95%CI: 0.871-0.990, P = 0.022) were independent significant factors associated with spontaneous remission in FUO. Conclusions This study suggested that most patients discharged with undiagnosed classic FUO would remit spontaneously. Thus, for patients with stable clinical conditions, follow-up and observation could be the best choice. Patients with lower level of some inflammatory factors may have a high likelihood of spontaneous remission in classic FUO.

[Clinical Characteristics of 68 Patients with Osteoarticular Tuberculosis].

Objective To analyze the clinical features of patients with osteoarticular tuberculosis. Method This retrospective study included a cohort of 68 osteoarticular tuberculosis patients hospitalized in Peking Union Medical College Hospital from January 2013 to December 2020.Results The patients included 42(61.8%)males and 26(38.2%)females,with a median age of 56 years.Tuberculosis pathogen was detected in 39(57.4%)patients,and 29(42.6%)patients were diagnosed by clinical manifestations.The median time from onset to diagnosis was 4 months.The most common manifestations were pain and dysfunction(86.8%),followed by fever(47.1%),weight loss(36.8%),and night sweats(13.2%).Concomitant active tuberculosis in other organs was observed in 27(39.7%)patients.Unifocal and multifocal osteoarticular tuberculosis occurred in 51(75.0%)patients and 17(25.0%)patients,respectively,which mainly attacked thoracic and lumbar spines.Tuberculosis T cell test was positive in 92.7% patients.All the bone biopsies revealed epithelioid granuloma with/without necrosis,with 75.0% positive for mycobacterial DNA,55.1% positive for mycobacterial culture,and 20% positive for acid-fast staining.The risk of developing multifocal osteoarticular tuberculosis in the patients with weight loss was 5.333 times(P=0.013)that of the patients with stable weight.Conclusions The diagnosis of osteoarticular tuberculosis is difficult and tuberculosis T cell test is an effective means.Bone biopsy is the key to diagnosis,and the PCR of mycobacterial DNA shows the highest positive derection rate.Multifocal osteoarticular tuberculosis is not rare,especially in the patients with weight loss.Thus,a comprehensive imaging evaluation is recommended to avoid missed diagnosis.

[Clinical Features and Risk Factors of Systemic Lupus Erythematosus Complicated with Cytomegalovirus Infection].

Objective To explore the clinical characteristics and risk factors of systemic lupus erythematosus(SLE)complicated with cytomegalovirus infection(CMV). Methods The medical records of patients diagnosed with SLE at discharge in the Department of Immunology at Peking Union Medical College Hospital between July 1,2017 and April 1,2019 were retrospectively reviewed,and the clinical and laboratory data related to CMV infection were analyzed. Results Of the 231 patients with SLE,115(49.8%)had CMV infection.Among them,78(67.8%)were asymptomatic CMV infection and 37(32.2%)were diagnosed with CMV disease.Univariate analysis showed the number of organs involved(P=0.015),presence of other infections(P=0.004),methylprednisolone pulse therapy(P=0.001),cumulative dose of prednisolone within 30 days(P=0.001),average dose of prednisolone within 30 days(P<0.001),intravenous cyclophosphamide(P=0.003),methylprednisolone pulse therapy plus immunosuppressants(P=0.001),Systemic Lupus Erythematosus Disease Activity Index 2000 at admission(P=0.018),and serum albumin(ALB)level≤30 g/L(P<0.001)were associated with CMV infection.Multivariate analysis showed presence of other infections(OR=8.003,95%CI=2.108-30.383,P=0.002),methylprednisolone pulse therapy plus immunosuppressants(OR=10.336,95%CI=2.107-50.711, P=0.004),and serum ALB≤ 30 g/L(OR=3.367,95%CI=1.157-9.796,P=0.026)were independent risk factors for CMV infection. Conclusion Presence of other infections,recent methylprednisolone pulse therapy plus immunosuppressants,and serum ALB≤30 g/L can increase the risk of CMV infection in patients with SLE.

[Clinical and Laboratory Characteristics of Disseminated Non-tuberculous Mycobacterial Disease].

Objective To explore the clinical and laboratory characteristics and the prognosis of disseminated non-tuberculous mycobacteria(NTM)diseases in human immunodeficiency virus(HIV)negative patients. Methods Cases of disseminated NTM disease were retrospectively collected in Peking Union Medical College Hospital from January 2012 to October 2018.Clinical manifestations,laboratory findings,treatment,and prognosis of these cases were retrieved from the electronic medical record system. Results Among the 23 HIV negative patients with disseminated NTM disease,21 had underlying diseases,with rheumatoid immune disease(n=7)as the most common one.The main clinical manifestation was fever(n=23).Laboratory tests showed anemia [hemoglobin(85.78±25.47)g/L],hypoalbuminemia [albumin 29(27-32)g/L],elevated erythrocyte sedimentation rate [(85.73±43.78)mm/h] and hypersensitive C-reactive protein [(112.00±70.90)mg/L],and reduction of lymphocyte count [0.69(0.29-2.10)×10 9/L].Lymphocyte subset analysis indicated reduction in CD4 + T cells [213(113-775)/µl],CD8 + T cells [267(99-457)/µl],B cells [39(4-165)/µl],and NK cells [88(32-279)/µl] and elevation of human leukocyte antigen-D related(HLA-DR),and CD38 expression in CD8 + T cells [HLA-DR +CD8 +/CD8 +,60(40-68)%;CD38 +CD8 +/CD8 +,81(65-90)%].The most common species of NTM was Mycobacterium intracellular(n=6).Lymphocyte,CD8 + T cell,B cell,and NK cell counts were significantly lower in dead patients than surviving patients(P =0.045,P=0.045,P=0.032,and P=0.010,respectively). Conclusions Disseminated NTM disease in HIV negative patients is mainly manifested as fever,anemia,hypoalbuminemia,and elevated inflammatory indicators.It is more likely to occur in immunocompromised patients.Patients with decreased lymphocytes,CD8 + T cells,B cells and NK cells tend to have a poor prognosis.

Diet and feeding behavior of a group of 42 Phayre's langurs in a seasonal habitat in Mt. Gaoligong, Yunnan, China.

In habitats such as temperate evergreen forests, fruit, and seed productivity is reported to exhibit marked changes in seasonal availability, such that fruit is most available in summer and seeds are most available in autumn. Primates living in these habitats, therefore, are expected to adjust their diets in response to the spatial and temporal variation in these food resources. We studied the diet and feeding behavior of a group of 42 Phayre's langurs (Trachypithecus phayrei) living in a northern (24°48'N) montane habitat (1,700-2,350 m) in Mt. Gaoligong, Yunnan, China from August 2012 to July 2013. The langurs were found to forage on 50 plant species, of which 28 species each accounted for more than 1% of their annual feeding time. Castanopsis echidnocarpa, the most abundant species in their habitat, accounted for 17.5% of the total forest trees, and contributed to the largest proportion of the annual langur diet. The primary component of the langur diet was composed of fruits (22.2%), seeds (18.7%), and buds and young leaves (41.5%). Mature leaves accounted for only 4.1% of their diet. Based on DBH and the percent of the crown containing edible food items, we found that the langurs changed their monthly diet according to the availability of fruits and seeds (Spearman rank correlation: r = 0.609, p = 0.035), and buds and young leaves (Spearman rank correlation: r = 0.837, p = 0.001). The seeds of C. echidnocarpa accounted for 12.5% of langur feeding time. A single tree produced a large seed and fruit crop, which likely reduced opportunities for within-group feeding competition. We argue that the resource productivity of this northern montane enables Phayre's langurs to live in stable groups that are 3.6 times larger than reported for Phayre's langurs living in other habitats.

Clinical and Laboratory Characteristics of Patients with Nontuberculous Mycobacterium Bloodstream Infection in a Tertiary Referral Hospital in Beijing, China.

BACKGROUND: Nontuberculous Mycobacterium (NTM) bloodstream infection (BSI) is relatively rare. We aimed in this study to evaluate the clinical characteristics, laboratory evaluation, and outcomes of patients with NTM BSI. METHODS: We retrospectively reviewed the clinical records of inpatients with NTM BSI at our institution between January 2008 and January 2015 and recorded clinical parameters including age, gender, underlying disease, clinical manifestation, organs involved with NTM disease, species of NTM, laboratory data, treatment and outcome of these patients. We also reviewed the reported cases and case series of NTM BSI by searching PubMed, EMBASE, and Wanfang databases. Data of normal distribution were expressed by mean ± standard deviation (SD). Data of nonnormal distribution were expressed by median and interquartile range (IQR). RESULTS: Among the ten patients with NTM BSI, the median age was 51 years (IQR 29-57 years) and three patients were males. Eight patients were immunocompromised, with underlying diseases including human immunodeficiency virus (HIV) infection (one patient), rheumatic diseases (two patients), breast cancer (one patient), myelodysplastic syndrome (two patients), and aplastic anemia (two patients). Other organ(s) involved were lung (two patients), endocardium (two patients), brain, spinal cord, and soft tissue (one each patient). The median lymphocyte was 0.66 × 109/L (IQR 0.24-1.93 × 109/L). The median cluster of differentiation 4 (CD4) cell count was 179/mm3 (IQR 82-619/mm3). Five patients died (three with hematological diseases, one with breast cancer, and one with rheumatic disease), three recovered, and two were lost to follow-up. CONCLUSIONS: We reported all cases in our hospital diagnosed with bloodstream NTM infection that was rarely reported. In this group of patients, patients usually had a high fever and could have multiple organ involvements. All patients with poor prognosis had underlying diseases.

Clinical and Laboratory Diagnosis of Intestinal Tuberculosis.

BACKGROUND: Tuberculosis (TB) remains a worldwide problem. Intestinal TB (ITB) constitutes a major public health problem in developing countries and has been associated with significant morbidity and mortality. The aim of this study was to characterize the clinical, radiological, endoscopic, and pathological features of ITB and to define the strategy for establishing the diagnosis. METHODS: A retrospective study (from January 2000 to June 2015) was carried out in Peking Union Medical College Hospital and all hospitalized cases were diagnosed as ITB during the study period were included. The relevant clinical information, laboratory results, microbiological, and radiological investigations were recorded. RESULTS: Of the 85 cases, 61 cases (71.8%) were ranged from 20 to 50 years. The ileocecal region was involved in about 83.5% (71/85) of patients. About 41.2% (35/85) of patients had co-existing extra ITB, especially active pulmonary TB. Abdominal pain (82.4%) was the most common presenting symptom followed by weight loss (72.9%) and fever (64.7%). Both T-cell spot of TB test (T-SPOT.TB) and purified protein derivatives (PPD) tests were performed in 26 patients: 20 (76.9%) positive T-SPOT.TB and 13 (50.0%) positive PPD were detected, with a statistical significant difference (P = 0.046). Twenty cases (23.5%) were histopathology and/or pathogen confirmed TB; 27 cases (31.8%) were diagnosed by clinical manifestation consistent with ITB and evidence of active extra ITB; 38 cases (44.7%) were diagnosed by good response to diagnostic anti-TB therapy. CONCLUSIONS: ITB is difficult to diagnose even with modern medical techniques due to its nonspecific clinical and laboratory features. At present, combination of clinical, endoscopic, radiological, and pathological features continues to be the key to the diagnosis of ITB.

Diagnostic Value of T-cell Interferon-γ Release Assays on Synovial Fluid for Articular Tuberculosis: A Pilot Study.

BACKGROUND: Tuberculosis (TB) remains a major global public health challenge. Articular TB is an important form of extrapulmonary tuberculosis, and its diagnosis is difficult because of the low sensitivity of traditional methods. The aim of this study was to analyze the diagnostic value of T-SPOT.TB on synovial fluid for the diagnosis of articular TB. METHODS: Patients with suspected articular TB were enrolled consecutively between August 2011 and December 2015. T-SPOT.TB was performed on both synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs). The final diagnosis of articular TB was independent of the T-SPOT.TB result. The diagnostic sensitivity, specificity, predictive value, and likelihood ratio of T-SPOT.TB on SFMCs and PBMCs were analyzed. RESULTS: Twenty patients with suspected articular TB were enrolled. Six were diagnosed with articular TB, and 14 patients were diagnosed with other diseases. Sensitivity and specificity were 83% and 86% for T-SPOT.TB on SFMCs, and 67% and 69% for T-SPOT.TB on PBMCs, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of T-SPOT.TB on SFMCs were 71% and 92%, respectively. The PPV and NPV were 50% and 82% for T-SPOT.TB on PBMCs. CONCLUSION: Sensitivity, specificity, and NPV of T-SPOT.TB on SFMCs appeared higher than that on PBMCs, indicating that T-SPOT.TB on SFMCs might be a rapid and accurate diagnostic test for articular TB.

Major causes of fever of unknown origin at Peking Union Medical College Hospital in the past 26 years.

BACKGROUND: Despite the recent advances in medicine, fever of unknown origin (FUO) remains a diagnostic and therapeutic challenge even to expert physicians. To increase the knowledge of FUO, we conducted a retrospective study to investigate the causes of FUO and the change of major causes of FUO during the past 26 years. METHODS: The clinical data were retrospectively analyzed from 997 patients with FUO hospitalized at the Peking Union Medical College Hospital (PUMCH) between January 2004 and October 2010. Furthermore, the results were compared to that reported in previous studies of FUO in PUMCH since 1985. RESULTS: Of the 997 FUO cases, definite diagnosis was eventually achieved in 797 (79.9%) patients. The most common cause of FUO was infectious diseases (479 cases, 48.0%), with tuberculosis accounting for 45.3% (217/479) of the cases of infections. One hundred and sixty-eight (16.9%) patients were diagnosed with connective tissue diseases, with Still's disease and vasculitis accounted for 31.5% (53/168) and 24.4% (41/168) of this category, respectively. Neoplasms and miscellaneous causes were found in 7.9% (79/997) and 7.1% (71/997), respectively. However, no definite diagnosis had been made in the remaining 200 (20.1%) cases until they were discharged from the hospital. CONCLUSIONS: During different periods, infectious diseases, especially tuberculosis, were the leading etiology of FUO and the proportion of tuberculosis had no significant difference. While the frequency of neoplasms was descending, the proportion of lymphoma in neoplasm was ascending; the frequency of undiagnosed cases was increasing, but in most FUO cases the causes can be diagnosed eventually after careful analysis of clinical data.

Gene chip array for differentiation of mycobacterial species and detection of drug resistance.

BACKGROUND: Gene chip array can differentiate isolated mycobacterial strains using various mycobacterium specific probes simultaneously. Gene chip array can evaluate drug resistance to isoniazid and rifampin of tuberculosis strains by detecting drug resistance related gene mutation. This technique has great potential for clinical application. We performed a retrospective study to investigate the capability of gene chip array in the rapid differentiation of species and detection of drug resistance in mycobacterium, and to evaluate its clinical efficacy. METHODS: We selected 39 patients (54 clinical mycobacterium isolates), used gene chip array to identify the species of these isolates and detect drug resistance to isoniazid and rifampin in Mycobacterium tuberculosis isolates. Meanwhile, these patients' clinical data were analyzed retrospectively. RESULTS: Among these 39 patients whose mycobacterium culture were positive, 32 patients' isolates were identified as Mycobacterium tuberculosis, all of them were clinical infection. Seven patients' isolates were identified as non-tuberculosis mycobacterium. Analyzed with their clinical data, only two patients were considered as clinical infection, both of them were diagnosed as hematogenous disseminated Mycobacterium introcellulare infection. The other five patients' isolates were of no clinical significance; their clinical samples were all respiratory specimens. Clinical manifestations of tuberculosis and non-tuberculous mycobacterial infections were similar. Isoniazid resistance was detected in two tuberculosis patients, while rifampin resistance was detected in one tuberculosis patient; there was another patient whose Mycobacterium tuberculosis isolate was resistant to both isoniazid and rifampin (belongs to multidrug resistance tuberculosis). The fact that this patient did not respond to routine anti-tuberculosis chemotherapy also confirmed this result. CONCLUSIONS: Gene chip array may be a simple, rapid, and reliable method for the identification of most mycobacterial species and detection of drug resistance in Mycobacterium tuberculosis. It is useful in diagnosis, treatment, and hospital infection control of mycobacterial infections, and it may have a great potential for clinical application.

[A clinical analysis of AIDS-related non-Hodgkin lymphoma in 5 patients and review of literature].

OBJECTIVE: To analyze the clinical characteristics of AIDS-related non-Hodgkin lymphoma (ARL) and review relative literature for the diagnosis and treatment of ARL. METHOD: The clinical data of ARL patients admitted to Peking Union Medical College Hospital from April 2009 to April 2011 were retrospectively analyzed. RESULTS: Five male ARL patients aged 32 to 65 years old were included in this retrospective study. Among them, two patients were found to be HIV-positive for the first time, three were on regular highly active anti-retroviral therapy (HAART) for 7 - 8 months before the emergence of lymphoma-related symptoms. CD(4)(+) T cell count was (69 - 232) × 10(6)/L at presentation. Two patients firstly presented with sore throat and throat ulcer, one with cervical nodules, one with pelvic mass, one with fever and edema in right thigh. Through pathological analysis, four patients had B cell-originated lymphoma, with one Burkitt lymphoma and three diffuse large B cell lymphomas; one patient had T-cell lymphoma. Four patients were treated with chemotherapy, with one complete remission, one relapse, one non-response, and one death. One patient had radiotherapy only and had progressed disease. Bone marrow suppression and gastrointestinal disturbance were the main adverse effects of chemotherapy. CONCLUSIONS: Lymphoma should be considered in any HIV-infected patients presented with unexplainable adenopathy, recurrent sore throat or throat ulcer, or fever of unknown origin. Biopsy should be rigorously carried out. Appropriate chemotherapy, together with HAART, may improve the prognosis greatly.

[Clinical significance of positive sputum culture for filamentous fungi].

OBJECTIVE: To investigate the clinical significance of positive sputum culture for filamentous fungi. METHODS: The medical data of 140 patients positive for filamentous fungi in sputum culture at Peking Union Medical College Hospital were reviewed retrospectively. Based on the diagnostic criteria by European Organization for Research and Treatment of Cancer/Mycoses Study Group, invasive pulmonary fungal infection (IPFI) was diagnosed. The clinical characteristics of cases with and without IPFI were analyzed respectively. RESULTS: Among all 140 cases positive for filamentous fungi in sputum culture, only 22 cases could be diagnosed as IPFI. Two of 22 IPFI cases were confirmed by post-operative pathology, 1 case was confirmed by positive blood culture for filamentous fungi and the remaining 19 cases were diagnosed clinically according to the nature of hosts, characteristics of pulmonary infections and microbiological evidence (positive sputum culture for filamentous fungi, 2 - 5 times for each case). Most of etiological fungi in IPFI patients belonged to Aspergillus. And the identity of isolated fungal strain was mostly one strain for each patient. In IPFI group, patients who had been treated with broad-spectrum antibiotics (100%), steroids (13, 59.1%) or immunosuppressant (7, 31.8%) or who had pulmonary X-ray imaging changes (100%), primary diseases (21, 95.5%), hypoalbuminemia (18, 81.8%) or hemoptysis (10, 45.5%), were significantly more than those in non-IPFI group (66.9%, 34.7%, 18.6%, 79.7%, 72.0%, 45.8% and 4.2% respectively; P < 0.05 for each item). In IPFI group, itraconazole, amphotericin B and/or voriconazole were administrated, 8 patients (36.4%) were cured and 14 patients (63.6%) passed away. In non-IPFI group, the patients were treated with antibiotics, fluconazole, anti-tuberculosis, steroids or combined with immunosuppressant, chemotherapy or bronchoalveolar lavage; 96 cases (81.4%) were cured or showed improvement, and 22 cases (18.6%) died or gave up further treatment. CONCLUSIONS: The clinical significance of positive sputum culture for filamentous fungi are associated with the times of positive culture, the number and species of isolated fungal strains. Meanwhile it is important to determine whether there is IPFI according to the nature and clinical characteristics of patients.

[An analysis of 100 cases of tuberculosis first presenting as fever of unknown origin in a general tertiary hospital].

OBJECTIVE: To investigate the clinical characteristics of tuberculosis (TB) first presenting as fever of unknown origin (FUO). METHODS: The clinical data of 100 cases of FUO, diagnosed as TB finally, among in-patients in Peking Union Medical College Hospital were analyzed retrospectively. RESULTS: (1) Sites of TB:there were 39 patients with merely pulmonary TB, 28 patients with merely extrapulmonary TB, and 33 patients with both pulmonary and extrapulmonary TB. (2) CLINICAL MANIFESTATIONS: depending on the different sites of tuberculous lesion, the clinical symptoms varied accordingly. The common laboratory findings included anemia, hypoalbuminemia, elevation of the level of ESR and C-reactive protein (CRP). (3) Methods for diagnosis: 34 cases were diagnosed by sputum smear- or cultivation-positive for acid-fast bacilli; 8 cases by histopathology; 49 cases by clinical diagnosis of TB with an effective anti-TB therapy; and 9 cases by effective diagnostic anti-TB therapy. (4) Responses to treatment: among 73 cases with complete follow-up data, only 2 cases (2.7%) died and the other cases were cured or alleviated. Fifty-five cases (77.5%) showed marked efficacy after less than 4 weeks of regular anti-TB therapy, 37 cases (52.1%) suffered adverse effects of anti-TB agents, and all of them had improved after modifying anti-TB therapy and supporting treatment. CONCLUSIONS: The diagnosis of TB that presents as FUO is quite difficult, and the median interval time for making diagnosis is 14 weeks (3 - 77 weeks). Investigating clinical manifestations comprehensively, reviewing radiology data carefully, and eliciting microbiological and pathologic evidence of TB, are extremely important for making the correct diagnosis. In some cases, a therapeutic trial of anti-TB therapy is necessary.

Single-walled carbon nanotubes: geno- and cytotoxic effects in lung fibroblast V79 cells.

With the development of nanotechnology, there is a tremendous growth of the application of nanomaterials, which increases the risk of human exposure to these nanomaterials through inhalation, ingestion, and dermal penetration. Among different types of nanoparticles, single-walled carbon nanotubes (SWCNT) with extremely small size (1 nm in diameter) exhibit extraordinary properties and offer possibilities to create materials with astounding features. Since the release of nanoparticles in an enclosed environment is of great concern, a study of possible genotoxic effects is important. Our previous data showed that pharyngeal aspiration of SWCNT elicited pulmonary effects in C57BL/6 mice that was promoted by a robust, acute inflammatory reaction with early onset resulting in progressive interstitial fibrogenic response and the formation of granulomas. In the present study, the genotoxic potential of SWCNT was evaluated in vitro. The genotoxic effects of nanoparticles were examined using three different test systems: the comet assay and micronucleus (MN) test in a lung fibroblast (V79) cell line, and the Salmonella gene mutation assay in strains YG1024/YG1029. Cytotoxicity tests showed loss of viability in a concentration- and time-dependent manner after exposure of cells to SWCNT. Results from the comet assay demonstrated the induction of DNA damage after only 3 h of incubation with 96 microg/cm2 of SWCNT. The MN test indicated some but not significant micronucleus induction by SWCNT in the V79 cell line at the highest concentrations tested. With two different strains of Salmonella typhimurium, no mutations were found following SWCNT exposure.

[Effects of Naoyaojia on structural mechanical properties of femur in rats].

OBJECTIVE: To study the effect of long term Naoyaojia administration on the structural mechanical properties of rat femurs. METHOD: Young wistar rats were treated orally with Naoyaojia at doses of 3, 6, and 12 mg/kg body weight every 2 weeks for 1 year. Beary's bending test was used for determining physical properties of the femur. RESULT: The thickness of the cortex and cross-sectional area of femur increased significantly in animals treated with 3 mg/kg dose of Naoyaojia (P<0.01), significant increase in maximum bending load was also found in this group compared with the control group (P<0.01). But an opposite change was found in animals treated with 12 mg/kg dose of Naoyaojia. CONCLUSION: Stimulation on the thickness of the cortex along the axis as well as the maximum bending load of femurs are found in animals treated with 3 mg/kg dose of Naoyaojia, but negative effects were observed at higher dose level.