[Clinical characteristics and risk factors for bronchoscopic airway mucus hypersecretion in childhood pneumonia infected by different pathogens].

Objective: To investigate the risk factors for airway mucus hypersecretion in childhood pneumonia infected by different pathogens. Method: A retrospective cohort included 968 children who were hospitalized for Mycoplasma pneumoniae pneumonia (MPP), respiratory syncytial virus (RSV) pneumonia, adenovirus pneumonia and underwent bronchoscopy in Respiratory Department of Children's Hospital of Chongqing Medical University from January 2019 to December 2021 was conducted. The children were divided into two groups distinguished by airway mucus secretion according to the airway mucus hypersecretion score which were scored according to the mucus secretion under the bronchoscope. The demographic characteristics, clinical characteristics, laboratory tests and disease severity of the two groups were compared. And the risk factors for the development of airway mucus hypersecretion in two groups were analyzed. Chi square test, Mann-Whithey U test and Fisher exact test were used to analyze the differences between the two groups, and multivariate Logistic regression was used to analyze the influencing factors. Result: There were 559 males and 409 females in the 968 children, with an age of 4.0 (1.4, 6.0) years. Among the 642 children with MPP, 185 cases were in the hypersecretion group and 457 cases were in the non-hypersecretion group. There were 41 cases in the hypersecretion group and 160 cases in the non-hypersecretion group of 201 children with RSV pneumonia. In the 125 children with adenovirus pneumonia, there were 39 cases in the hypersecretion group and 86 cases in the non-hypersecretion group. In these children, the age of children in the hypersecretion group was older than that in the non-hypersecretion group (6.0 (4.0, 7.0) vs. 5.0 (3.0, 7.0) years old, 1.5 (0.5, 3.6) vs. 0.8 (0.4, 1.6) years old, 2.0 (1.2, 4.5) vs. 1.3 (0.8, 2.0) years old, U=35 295.00, 2 492.00, 1 101.00, all P<0.05). Through multivariate Logistic regression analysis it found that increased risk of airway mucus hypersecretion was present in childhood MPP with increase in peripheral blood white blood cell count (OR=3.30, 95%CI 1.51-7.93, P=0.004) or increase in neutrophil ratio (OR=2.24, 95%CI 1.16-4.33, P=0.016) or decrease in lymphocyte count (OR=3.22, 95%CI 1.66-6.31, P<0.001) or decrease in serum albumin (OR=2.00, 95%CI 1.01-3.98, P=0.047). The risk of airway mucus hypersecretion was increased in children with RSV pneumonia combined with elevated peripheral blood eosinophils (OR=3.04, 95%CI 1.02-8.93, P=0.043). Meanwhile, airway mucus hypersecretion was associated with severe pneumonia (OR=2.46, 95%CI 1.03-6.15, P=0.047) in children with RSV pneumonia. Older age was associated with increased risk of airway mucus hypersecretion in children with adenovirus pneumonia (OR=1.02, 95%CI 1.00-1.04, P=0.026). In these children with occurrence of pulmonary rales, wheezes or sputum sounds (OR=3.65, 95%CI 1.22-12.64, P=0.028) had an increased risk of airway mucus hypersecretion. Neutrophils in bronchoalveolar lavage fluid (BALF) demonstrated higher ratio in hypersecretion group from children with MPP (0.65 (0.43, 0.81) vs. 0.59 (0.34, 0.76), U=24 507.00, P<0.01), while the proportion of macrophages in BALF was lower (0.10 (0.05, 0.20) vs. 0.12 (0.06, 0.24), U=33 043.00, P<0.05). Nucleated cell count and neutrophil ratio in BALF were higher in hypersecretion group of children with RSV pneumonia (1 210 (442, 2 100)×106 vs. 490 (210, 1 510)×106/L, 0.43 (0.26, 0.62) vs. 0.30 (0.13, 0.52), U=2 043.00, 2 064.00, all P<0.05). Conclusions: The increase in peripheral blood white blood cell count, neutrophil ratio and decrease in lymphocyte count, serum albumin in children with MPP is related to the development of airway mucus hypersecretion. In children with RSV pneumonia, the abnormal increase of eosinophils in peripheral blood has relationship with hypersecretion. The appearance of lung rale, wheezing, and sputum rale are associated with airway mucus hypersecretion in children with adenovirus pneumonia. In addition, local neutrophil infiltration in the respiratory tract is closely related to the occurrence of airway mucus hypersecretion caused by Mycoplasma pneumoniae and RSV infection.

[The correlation study on human respiratory syncytial virus daily incidence and meteorological parameters in the main urban area of Chongqing from 2009 to 2019].

Objective: To explore the relationship between the daily incidence of human respiratory syncytial virus (HRSV) and meteorological parameters in the main urban area of Chongqing. Methods: This study took 3 107 children hospitalized with acute lower respiratory tract infections from June 2009 to June 2019 in department of Respiratory medicine, Children's Hospital of Chongqing Medical University (CHCMU). Nasopharyngeal aspirate (NPA) was collected on the day of admission to detect HRSV and common respiratory virus; combined with the meteorological data of the main urban area of ​​Chongqing during the same period, the correlation and distribution lag nonlinear model analysis of the daily incidence of HRSV and meteorological parameters were carried out. Results: Among 3 107 children, HRSV positive accounted for 34.53% (1 073 cases), the age was 6 (3, 13) months, and males accounted for 64.31% (690 cases). The daily incidence of HRSV was negatively correlated with minimum temperature (r=-0.220, P<0.001), maximum temperature (r=-0.221, P<0.001), average temperature (r=-0.221, P<0.001) and precipitation (r=-0.052, P<0.001), and positively correlated with sunshine time (r=0.011, P<0.001) and average relative humidity (r=0.095, P<0.001). Compared with the reference temperature (20 ℃), when the lowest temperature of 6-10 ℃ lags for 4-8 d, the RR value of HRSV was 1.11-1.14, and when the lowest temperature of 5-19 ℃ lags for 5 d and 2-19 ℃ lags for 10 d, the RR values were 1.02-1.14 and 1.00-1.03. When the cumulative lag is 5, 10, 15 and 21 d, compared with the reference temperature (20 ℃), the RR (95%CI) values at the lowest temperature of 10.4 ℃ were 1.93 (1.08-3.46), 3.49 (1.64-7.45), 5.00 (2.01-12.46) and 6.69 (2.18-20.48); the RR (95%CI) values of the lowest temperature of 22.1 ℃ were 0.87 (0.77-0.98), 0.77 (0.66-0.90), 0.74 (0.62-0.89) and 0.68 (0.55-0.85). In the cumulative effect, compared with the reference temperature (20 ℃), the gender stratification showed that the maximum RR (95%CI) values of the lowest temperature for boys and girls under different lag days were 7.24 (1.84-28.51) and 2.19 (1.07-4.46), the age stratification showed that the maximum RR (95%CI) values of the lowest temperature for children<6 months old and children ≥6 months old under different lag days were 4.72 (1.05-21.23) and 11.98 (1.70-84.35). Conclusions: In the main urban area of Chongqing, the daily incidence of HRSV in children is correlated with climatic parameters. Among them, the lowest temperature has a delayed and cumulative effect on HRSV infection. 6-10 ℃ has a greater impact on the incidence of HRSV when the lag is 4-8 days. The effect has a more obvious impact on the incidence of HRSV in boys and children ≥ 6 months.

[Clinical effect and economic benefit evaluation of minimally invasive surgery for drivers with lumbar disc herniation].

Objective: To investigate the clinical effect of minimally invasive surgery in the treatment of professional drivers with lumbar disc herniation. Methods: 126 patients with lumbar disc herniation admitted to hospital from June 1, 2015 to December 30, 2018 were selected and divided into observation group (59 cases treated by percutaneous transforaminal endoscopy) and control group (67 cases treated with conventional conservative treatment) according to the treatment methods. The Visual Analogue Scale (VAS) and Japanese Orthopaedic Association Scores (JOA) before and after treatment were analyzed retrospectively. Length of stay, time out of bed, hospitalization expenses and recurrence rate were evaluated. The measurement data was expressed by x±s, the comparison between groups was performed by t test, and the count data were analyzed by descriptive analysis. Results: Before treatment, there was no significant difference in gender, age, VAS score and JOA score between the two groups (P>0.05) . After treatment, compared with the control group, the VAS score of the observation group was lower, the JOA score was higher, the time out of bed was shorter, the average hospitalization time was reduced, the average hospitalization cost was higher, and the recurrence rates after Six months and one year were lower in the observation group, the differences were statistically significant (P<0.05) . Conclusion: The clinical effect of percutaneous transforaminal endoscopic treatment is better than that of conventional conservative treatment for driver＇s lumbar disc herniation.

Role of spinal cyclooxygenase-2 and prostaglandin E2 in fentanyl-induced hyperalgesia in rats.

BACKGROUND: Accumulated evidence suggests that spinal cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) may be implicated in the development of opioid-induced hyperalgesia. METHODS: Rats received subcutaneous fentanyl injections at different doses (20-80 µg kg-1), four separate times at 15-min intervals. Some rats only received fentanyl (60 µg kg-1 × 4 doses) with or without surgical incision. Fentanyl-induced hyperalgesia was evaluated via a tail-pressure or paw-withdrawal test. The concentrations of spinal COX-2, EP-1 receptor (EP-1R) mRNA, and PGE2 were measured. The effects of the COX-2 inhibitor, parecoxib (intraperitoneal 10 mg kg-1), or the EP-1R antagonist, SC51089 (intraperitoneal 100 µg kg-1), on hyperalgesia and spinal PGE2 were examined. RESULTS: Acute repeated injections of fentanyl dose-dependently induced mechanical hyperalgesia, which reached a peak at the 1st day and persisted for 1-4 days postinjection. This hyperalgesia could be partly or totally prevented by the pretreatment of either parecoxib or SC51089. Consistently, the levels of spinal COX-2 mRNA and PGE2 were also dose-dependently increased, reaching a peak at the first day and persisting for 2 days postinjection. Pretreatment with parecoxib could block the increase in spinal PGE2 and had no effects on spinal COX-2 and EP-1R mRNA. Fentanyl injection enhanced incision-induced mechanical and thermal hyperalgesia. CONCLUSIONS: Acute repeated fentanyl administration dose-dependently produced mechanical hyperalgesia and augmented surgery induced postoperative hyperalgesia. This behavioural change was paralleled with an increase in spinal COX-2 mRNA and PGE2 after fentanyl administration. Inhibition of COX-2 or blockade of EP-1R can partly or totally prevent hyperalgesia.

[Pleural amoebic empyema: a case report].

In this paper, a case of pleural amoebic empyema and its diagnosis and treatment were reported.

Ensemble-based simultaneous emission estimates and improved forecast of radioactive pollution from nuclear power plant accidents: application to ETEX tracer experiment.

The accidental release of radioactive materials from nuclear power plant leads to radioactive pollution. We apply an augmented ensemble Kalman filter (EnKF) with a chemical transport model to jointly estimate the emissions of Perfluoromethylcyclohexane (PMCH), a tracer substitute for radionuclides, from a point source during the European Tracer Experiment, and to improve the forecast of its dispersion downwind. We perturb wind fields to account for meteorological uncertainties. We expand the state vector of PMCH concentrations through continuously adding an a priori emission rate for each succeeding assimilation cycle. We adopt a time-correlated red noise to simulate the temporal emission fluctuation. The improved EnKF system rapidly updates (and reduces) the excessively large initial first-guess emissions, thereby significantly improves subsequent forecasts (r = 0.83, p < 0.001). It retrieves 94% of the total PMCH released and substantially reduces transport error (>80% average reduction of the normalized mean square error).

Single nucleotide polymorphisms in the ORM1-like 3 gene associated with childhood asthma in a Chinese population.

Single nucleotide polymorphism (SNP)-based genome-wide association studies have revealed that polymorphisms of the ORM1-like 3 (ORMDL3) gene are associated with childhood asthma. We investigated genetic associations of SNPs in and around the ORMDL3 gene with childhood asthma in a Chinese population. Genomic DNA was extracted from peripheral venous blood drawn from 152 subjects with childhood asthma and from 190 control subjects. SNP genotyping was performed with the MassARRAY system (Sequenom) by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Among the six SNPs, only the genotype frequencies of rs7216389 were significantly different between asthmatic children and controls. Asthmatic children had a significantly higher frequency of T alleles [odds ratio (OR) = 1.653, 95% confidence interval (95%CI) = 1.170-2.333] in rs7216389, than controls. The TT genotype of rs7216389 was found to be a significant risk factor for childhood asthma by logistic regression analysis (OR = 1.704, 95%CI = 1.105-2.628). There was no significant association between the TT genotype of rs7216389 and clinical features of childhood asthma. We conclude that the ORMDL3 gene influences childhood asthma and that the TT genotype of the rs7216389 polymorphism is associated with childhood asthma in the Chinese population.

Establishing a new electrical conduction pathway by anastomosis of the right auricle and right ventricle assisted by mesenchymal stem cells in a canine model.

BACKGROUND: Electronic pacemakers are the primary treatment of complete atrioventricular (AV) block, but their use is associated with many complications. The aim of the present study was to create an alternative treatment for these patients. MATERIALS AND METHODS: Mesenchymal stem cells (MSCs) isolated from the bone marrow of a 3-month-old dog were cultured in vitro. The MSCs were labeled with 4', 6-diamidino-2-phenylindole (DAPI) before transplantation. We anastomosed the right auricle and right ventricle in 24 dogs, and transplanted labelled MSCs into the anastomotic area of 8 dog hearts. Using immunostaining we assessed survival and differentiation of the implanted cells at 8 weeks posttransplantation. Electrocardiography confirmed the secondary electrical conduction pathway. RESULTS: The ventricular current was captured by the electronic pacemaker in 21 dogs. Compared with the control group (surgery alone), pacemaker stimulus current was significantly less in the MSC group (surgery+MSCs). CONCLUSIONS: Anastomosis of the right auricle and right ventricle assisted by MSCs may be a new treatment for patients with complete AV block in the future.

Estival distribution of dissolved metal concentrations in Liaodong Bay.

The temporal and spatial distributions of Cu, Pb, Zn, and Cd in surface water of the Liaodong Bay were studied based on samples collected at 16 sites in June and August from 2001 to 2005. The temporal distribution showed decreasing trends. The concentrations of dissolved metals in the Liaodong Bay were 4.34, 3.21, 31.54, and 0.995 mug/L for Cu, Pb, Zn, and Cd, respectively. Cu and Pb were scattered near the estuaries, and Zn and Cd were mainly found near the Wuli River. Rivers were the main metals pollution sources in the Bay.

Distribution of polycyclic aromatic hydrocarbons in thirty typical soil profiles in the Yangtze River Delta region, east China.

Polycyclic aromatic hydrocarbons (PAHs) were quantified in 30 soil profiles from the Yangtze River Delta Region, in east China. Relative concentrations of PAH compounds with different benzene rings and ratios of fluoranthene to fluoranthene plus pyrene and benz(a)anthracene to benz(a)anthracene plus chrysene were used to identify the possible sources of soil PAHs. Total concentrations of 15 PAHs in topsoils ranged from 8.6 to 3881 microg kg(-1) with an average of 397 microg kg(-1). Half of the soil samples were considered to be contaminated with PAHs (>200 microg kg(-1)) and two sampling sites were heavily polluted by PAHs with concentrations >1000 microg kg(-1). Phenanthrene was found in soils below a depth of 100 cm in half of the sampling sites, but the detectable ratio of benzo(a)pyrene decreased sharply from 100% in topsoil to 0 in the 4th horizon.

Bioaccumulation of nickel from aqueous solutions by genetically engineered Escherichia coli.

This study constructed a genetically engineered Escherichia coli JM109 which simultaneously expressed nickel transport system and metallothionein to remove and recover Ni(2+) from aqueous solution. Bioaccumulation process was rapid and followed linearized Langmuir isotherm. A more than six-fold increase of Ni(2+) binding capacity was obtained by genetically engineered E. coli cells compared with original host E. coli cells. A pH assay showed genetically engineered E. coli cells accumulated Ni(2+) effectively over a broad range of pH (4-10). The presence of 1000 mg/L Na(+) and Ca(2+), or 50mg/L Cd(2+) or Pb(2+) did not have a significant effect on Ni(2+) bioaccumulation, while Mg(2+), Hg(2+) and Cu(2+) posed a severe adverse influence on Ni(2+) uptake by genetically engineered E. coli. Furthermore, genetically engineered E. coli cells did not require extra nutrients for Ni(2+) bioaccumulation.

Evidence for non-circadian light/dark-regulated expression of Hsp70s in spinach leaves.

Expression of six Hsp70s in spinach (Spinacia oleracea cv Longstanding Bloomsdale) leaves grown under isothermal conditions is regulated by a light/dark (L/D) mechanism distinctly different from the light-regulated mechanism for the chlorophyll a/b-binding protein (cab) or small subunit of ribulose-1,5-bisphosphate carboxylase oxygenase (rbcS). Subjecting entrained plants to two or three L/D cycles within a 24-h period resulted in an equal number of oscillations in expression for five out of six 70-kD heat shock proteins (Hsp70s). Three cycles appear to be the maximum, as shorter L/D treatments do not consistently increase the number of cycles in a 24-h period. The expression response of Hsp70s to L/D is overridden by heat shock. Protein disulfide isomerase, a second molecular chaperone of the endoplasmic reticulum, has an expression pattern in entrained plants that is similar to hsc70-2, the endoplasmic reticulum luminal Hsp70 binding protein. The parallel expression patterns for the various Hsp70s and protein disulfide isomerase indicate a likely general coordinate L/D regulation for molecular chaperones in plants. Multiple inductions in response to successive L/D treatments within a 24-h period in entrained plants for five of six Hsp70s support the conclusion that expression is not a consequence of circadian control, but instead is independently cued by non-circadian-mediated L/D signals where peak Hsp70 expression precedes the daily thermoperiod maximum.

Hematological studies on DIC-like findings observed in patients with snakebite in south China.

To clarify the characteristics of the hematological disturbances evoked by snakebite, we measured the antithrombin III (AT-III) activity, alpha2-plasmin inhibitor (alpha2-PI) activity, fibrinogen concentration (Fg) and level of fibrin degradation products (FDP) in 21 patients envenomed by several snakes in south China between August 1998 and October 1999. The hematological changes observed were as follows: the mean activities of AT-III were decreased in patients bitten by Ophiophagus hannah (Oh.), Bungarus fasciatus (Bf.), Hydrophis cyanocinctus (Hc.), Rhabdophis subminiatus (Rs.), and Trimeresurus stejnegeri (Ts.), while those of alpha2-PI were decreased in all patients in the present study; Fg was not detectable in the case of Rs. bite, and the Fg concentration after Ts., Oh., Hc. and Bf. bites also decreased markedly thereby increasing the mean levels of FDP in all patients. It thus appeared that DIC-like syndrome was caused in patients envenomed by snakebite. In the present study, we found that patients who were bitten by Rs., which is still being classified as a non-venomous snake, exhibited complete defibrinogenation and severe hemorrhage without any evidence of severe multiple organ damage. We also found that patients with Ts. bite showed marked hemostatic disturbance without severe multiple organ damage. It is considered that such a discrepancy between the hematological findings and clinical symptoms could be a characteristic phenomenon of the DIC-like syndrome induced by snakebite, especially by Rs. and Ts. bites.

Modified AFLP technique for rapid genetic characterization in plants.

The standard amplified fragment-length polymorphism (AFLP) technique was modified to develop a convenient and reliable technique for rapid genetic characterization of plants. Modifications included (i) using one restriction enzyme, one adapter molecule and primer, (ii) incorporating formamide to generate more intense and uniform bands and (iii) using agarose gel electrophoresis. Sea oats (Uniola paniculata L.), pickerel-weed (Pontederia cordata L.), Bermudagrass (Cynodon dactylon L.) and Penstemon heterophyllus Lindl. were used to determine the ability to generate adequate resolution power with both self- and cross-pollinated plant species including cultivars, ecotypes and individuals within populations. Reproducibility of bands was higher in all the AFLP experiments compared to random amplified polymorphic DNA (RAPD). Formamide with or without bovine serum albumin improved band intensities compared to dimethyl sulfoxide and the standard reaction mixture with no organic solvents. Comparison between RAPD and modified AFLP using sea-oats population samples proved that modified AFLP exhibits (i) a low number of faint bands with increased specificity of amplified bands, (ii) a significantly higher number of polymorphic loci per primer, (iii) less primer screening time, (iv) easy scoring associated with fewer faint bands and (v) greatly enhanced reproducibility. The technique described here can be applied with a high degree of accuracy for plant genetic characterization.

Diurnal regulation of Hsp70s in leaf tissue.

Steady-state mRNA levels for three Hsp70s were found to be regulated by a distinctive light/dark mechanism in spinach leaves. Messenger RNAs for the chloroplast stromal and two cytosolic forms displayed a diurnal expression pattern under isothermal conditions that appeared to be independent of circadian control. While protein blot data showed relatively constant Hsp70 protein levels, the higher Hsp70 mRNA levels in the light paralleled the diurnal cycle of total cell protein synthesis. Fractionation studies showed that the major cytosolic Hsp70 cognate group was associated with polysomes. Therefore, the variation of Hsp70 mRNAs is consistent with the diurnal metabolic activity of plant photosynthetic cells in which the demand of protein biogenesis for chaperone function and tissue temperature are highest during the day.

Hemostatic disturbances observed in patients with snakebite in south China.

To investigate the hematological disorders after snakebite, we measured the maximum platelet aggregation rate (MAR), antithrombin III (AT-III) activity, alpha(2)-plasmin inhibitor (alpha(2)-PI) activity, concentration of fibrinogen (Fg) and fibrin degradation products (FDP) in 25 samples from 17 patients with snakebite in south China. The results obtained in the patients before application of antivenom and patients with Ophiophagus hannah (Oh.) bite were as follows: (1) the mean MAR values were significantly decreased in the case of the snakebites from Vipera russellii (Vr.) and Trimeresurus mucrosquamatus (Tm.); (2) the mean activities of AT-III were decreased in all patients in the present study; 3) the mean activities of alpha(2)-PI were significantly decreased in patients bitten by Deinagkistrodon acutus (Da.), Agkistrodon halys (Ah.), Vr., Trimeresurus stejnegeri (Ts.), Tm. and Naja naja atra (Nn.); (4) the mean concentrations of Fg were markedly decreased in patients bitten by Da., Ah., Vr., Ts. and Tm.; and (5) the mean levels of FDP were significantly increased in cases of Da., Vr. and Ts. bite, but not in Ah., Tm., Nn. and Oh. bite. The results of the present study indicate that disorders of platelet aggregation and the coagulation-fibrinolysis system are liable to occur in patients with snakebite from Da., Ah., Vr., Ts., Tm. and Nn. Furthermore, it appeared that disseminated intravascular coagulation (DIC) was evoked in some patients. Specific antivenom was found to be useful for improving the hemostatic disturbances after snakebite from Ah. and Nn.

Anisodamine as an effective drug to treat snakebites.

Anisodamine is a natural alkaloid drug isolated from the plant Anisodus tanguticus growing in western China. The chemical structure and pharmacological action are just like the cholinergic receptor blocking agents atropine or scopolamine. The specific characteristic of the drug is being able to relieve the dangerous situation of microcirculatory failure, especially in case of DIC or renal failure. The prognosis of the patients will be quite good. Another characteristic of the drug is that no serious toxic reaction occurs even in successive doses given intravenously up to 500 mg a day. This is about fifty times greater than a common dose of 10 mg. Since we begin with the drug as a routine medication for the symptomatic treatment of renal failure, DIC bleeding, and microcirculatory failure, we should say that the specific antivenin and anisodamine are two treasure drugs for snakebites.

Systematics of Amaryllidaceae based on cladistic analysis of plastid sequence data.

Cladistic analyses of plastid DNA sequences rbcL and trnL-F are presented separately and combined for 48 genera of Amaryllidaceae and 29 genera of related asparagalean families. The combined analysis is the most highly resolved of the three and provides good support for the monophyly of Amaryllidaceae and indicates Agapanthaceae as its sister family. Alliaceae are in turn sister to the Amaryllidaceae/Agapanthaceae clade. The origins of the family appear to be western Gondwanaland (Africa), and infrafamilial relationships are resolved along biogeographic lines. Tribe Amaryllideae, primarily South African, is sister to the rest of Amaryllidaceae; this tribe is supported by numerous morphological synapomorphies as well. The remaining two African tribes of the family, Haemantheae and Cyrtantheae, are well supported, but their position relative to the Australasian Calostemmateae and a large clade comprising the Eurasian and American genera, is not yet clear. The Eurasian and American elements of the family are each monophyletic sister clades. Internal resolution of the Eurasian clade only partially supports currently accepted tribal concepts, and few conclusions can be drawn on the relationships of the genera based on these data. A monophyletic Lycorideae (Central and East Asian) is weakly supported. Galanthus and Leucojum (Galantheae pro parte) are supported as sister genera by the bootstrap. The American clade shows a higher degree of internal resolution. Hippeastreae (minus Griffinia and Worsleya) are well supported, and Zephyranthinae are resolved as a distinct subtribe. An Andean clade marked by a chromosome number of 2n = 46 (and derivatives thereof) is resolved with weak support. The plastid DNA phylogenies are discussed in the context of biogeography and character evolution in the family.