OBJECTIVES: To evaluate the clinical utility and translational potential of a remote jaundice monitoring system for home-based screening of neonatal hyperbilirubinemia. METHODS: A prospective self-controlled study was conducted, enrolling 538 newborns with gestational age ≥35 weeks, birth weight ≥2 000 g, and postnatal age ≤14 days at the Women's Hospital of Nanjing Medical University from March to October 2023. Four screening protocols with different predictive indicators were developed based on the Chinese Neonatal Transcutaneous Hourly Bilirubin Nomogram. The effectiveness of the system was evaluated, and the feasibility of using the remote jaundice monitoring system in actual home settings was analyzed. RESULTS: A total of 538 paired transcutaneous bilirubin (TcB) and total serum bilirubin (TSB) measurements showed a strong correlation (r=0.85, P<0.001), with 95.0% (511/538) of samples within the 95% limits of agreement. Using TcB ≥ the 95th percentile as the predictive indicator, the system achieved 100% sensitivity, 46.2% specificity, and an area under the receiver operating characteristic curve of 0.731 (95%CI: 0.682-0.780). This approach could reduce unnecessary hospital visits by 41.4% (221/538). CONCLUSIONS The system integrates the QBH-801 transcutaneous bilirubinometer, intelligent early warning, and remote guidance services, establishing a closed-loop "hospital-to-home" management model. It demonstrates high safety and feasibility, with significant clinical translational value.
Humans ; Infant, Newborn ; Female ; Male ; Bilirubin/blood* ; Feasibility Studies ; Prospective Studies ; Hyperbilirubinemia, Neonatal/diagnosis* ; Neonatal Screening/methods* ; Jaundice, Neonatal/diagnosis*

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

AIM:To observe the toxic effects of zinc oxide nanoparticles(ZnO NPs)on cornea by constructing intoxicated model in vivo and in vitro.METHODS:Human corneal epithelial cells(HCEpiC)were cultured in vitro and exposed to different concentrations(0.5, 5, 12.5, 25, 50, 100, 250 μg/mL)of ZnO NPs for 24h. The cell culture medium without nano-solution was used as the blank control group. The viability of the cells was assessed by MTT assay. Three different concentrations(25, 50 and 100 μg/mL)of ZnONPs dispersions were exposed to the conjunctival sac of anesthetized mice three times a day for 7d consecutively. The phosphate buffered saline(PBS)eye group was the PBS control group. Corneal morphology was observed on 1, 3, 5 and 7d, and the eyes were removed on 8d for various laboratory examinations, including corneal pathological changes and expression levels of inflammatory factors(TNF-α, IL-6).RESULTS:After treatment of HCEpiC cells with different concentrations of ZnO NPs for 24h, the MTT results showed that Zno NPs cause damage to cells at 0.5 μg/mL, and the cell survival rate was about 80%(P<0.05). Half of the cells were killed at a dose of 5 μg/mL, the damaging effect on cells in the concentration range of 5～250 μg/mL was concentration-dependent(P<0.0001). After 7d of conjunctival capsule spotting in mice, dot-like staining of fluorescein was seen in the 25 μg/mL ZnO NPs and 50 μg/mL ZnO NPs groups. Localized circular fluorescein stained areas were seen in the corneas of the 100 μg/mL ZnO NPs group. HE staining showed that the corneal epithelial layer, stromal layer thickness and stromal layer immune cell number did not change significantly in the 25 μg/mL and 50 μg/mL ZnO NPs groups(all P>0.05), while the corneal epithelial layer thinned, the corneal stromal layer thickened and the stromal layer immune cells increased significantly in the 100 μg/mL ZnO NPs group(all P<0.05). Immunohistochemical staining showed that the number of corneal stromal immune cells producing TNF-α and IL-6 and the mean integral optical density(IOD)values of TNF-α and IL-6 were significantly higher in the 100 μg/mL ZnO NPs group than in the PBS control group(P<0.05), and the degree of inflammation response was concentration-dependent. Compared with the PBS control group, no significant increase in immune cell count and IOD values in the 25 μg/mL ZnO NPs and 50 μg/mL ZnO NPs groups(P>0.05).CONCLUSION:The toxic damaging effect of ZnO NPs on the cornea was confirmed from both in vitro and in vivo, which provided a theoretical basis for the ocular safety evaluation of ZnO NPs.

OBJECTIVE: To investigate the effect of Bushen Chushi decoction combined with platelet-rich plasma(PRP) to treat knee osteoarthritis(KOA) in early and middle stage and its regulation on TGF-β1 and Smad-1 expression in serum. METHODS: Total of 45 patients with KOA in early and middle stage from May 2020 to April 2022 were treated and divided into control group and observation group. In control group, there were 30 patients including 12 males and 18 females, aged from 43 to 69 years old with an average of(57.3±6.5) years old and disease duration ranged from 1.5 to 5.0 years with an average of(3.8±1.7) years, and there were 8 cases in gradeⅠ, 13 cases in gradeⅡ, and 9 cases in grade Ⅲ according to Kellgren-Lawrence Grade, PRP 5 ml was injected into knee joint on the first day of No1, 3 week together for 2 times. In the observation group, there were 15 cases including 7 males and 8 females, aged from 45 to 70 years old with an average of (56.7±6.2) years old and disease duration ranged from 1.8 to 5.7 years with an average of (4.0±1.8) years, there were 4 cases in gradeⅠ, 9 cases in gradeⅡand 4 cases in grade Ⅲ according to the Kellgren-Lawrence Grade, PRP 5 ml were injected into knee joints that the time and frequency were the same as those in the control group, and at the same time Bushen Chushi decoction orally were taken 1 dose per day with a total of 28 doses. All patients were treated for four weeks. Visual analogue scale(VAS) and Lequesne MG score before and after treatment were used to evaluate improvement of knee pain and joint function. The TGF-β1 and Smad-1 levels in serum were measured before and after treatment in two groups. The incidence of complications in two groups was observed. RESULTS: All patients were followed up for 26 to 30 days with an average of (28.0±0.6) days. There was no significant difference in VAS and knee Lequesne MG scores between two groups before treatment(P>0.05). The scores of VAS and knee Lequesne MG on the first day after treatment in both groups were lower than those before treatment(P<0.05). The VAS and knee Lequesne MG scores in observation group were lower than those in control group(P<0.05) on the first day after treatment. The TGF-β1 level in serum after treatment were higher significantly than that before treatment in two groups(P<0.05). After treatment, TGF-β1 level in serum in observation group were lower than those in control group with statistically significant differences(P<0.05). The Smad-1 levels in serum after treatment in observation group were higher significantly than that in control group(P<0.05). The levels of Smad-1 were not statistically significant between before and after treatment(P>0.05). There was no significant difference in postopertaive complications between two groups (P>0.05). CONCLUSION The efficacy of Bushen Chushi decoction combined with PRP in treatment of early and middle KOA is better than that of PRP injection alone. The combined treatment could reduce TGF-β1 level and increase Smad-1 level in serum, which may be a mechanism to inhibit inflammation and alleviate cartilage degeneration to some extent.

Objective: To investigate the early effect and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with a 10-day decitabine-containing conditioning regimen in the treatment of acute myeloid leukemia (AML) /myelodysplastic syndrome (MDS) . Methods: From April 2021 to May 2022, 31 AML/MDS patients who received allo-HSCT with a 10-day decitabine-containing conditioning regimen were analyzed. Results: AML (n=10), MDS-AML (n=6), CMML-AML (n=1), and MDS (n=14) were identified in 31 patients, 16 males, and 15 females, with a median age of 41 (20-55) yr. Neutrophils and platelets were successfully implanted in 31 patients (100%), with a median implantation duration of 12 (9-30) and 14 (9-42) days, respectively. During the preconditioning period, 16 patients (51.6%) developed oral mucositis, with 15 cases of Ⅰ/Ⅱ grade (48.4%) and one case of Ⅲ grade (3.2%). After transplantation, 13 patients (41.9%) developed CMV viremia, six patients (19.4%) developed hemorrhagic cystitis, and four patients (12.9%) developed a local infection. The median time of acute graft versus host disease (aGVHD) following transplantation was 33 (12-111) days. The cumulative incidence of aGVHD and Ⅲ/Ⅳ grade aGVHD was 41.9% (95% CI 26.9%-61.0%) and 22.9% (95% CI 13.5%-47.5%), respectively. There was no severe cGVHD, and mild and moderate chronic GVHD (cGVHD) incidence was 23.5% (95% CI 12.1%-43.6%). As of November 30, 2022, only one of the 31 patients had relapsed, with a 1-yr cumulative relapse rate (CIR) of 3.2% (95% CI 0.5%-20.7%). There was only one relapse patient death and no non-relapse deaths. The 1-yr overall survival (OS) and disease-free survival (DFS) rates were 92.9% (95% CI 80.3%-100%) and 96.8% (95% CI 90.8%-100%), respectively. Conclusions: A 10-day decitabine-containing conditioning regimen for allo-HSCT reduced relapse and was safe and feasible in treating AML/MDS.
Male ; Female ; Humans ; Decitabine ; Myelodysplastic Syndromes/therapy* ; Leukemia, Myeloid, Acute/complications* ; Disease-Free Survival ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Recurrence ; Chronic Disease ; Graft vs Host Disease/etiology* ; Transplantation Conditioning/adverse effects* ; Bronchiolitis Obliterans Syndrome ; Retrospective Studies

Objective: To analyze the incidence and related factors of drug resistance in HIV-infected pregnant and postpartum women in some areas of three western provinces of China from 2017 to 2019. Methods: From April 2017 to April 2019, face-to-face questionnaires and blood sample testing were conducted in all health care institutions providing maternal and perinatal care and midwifery-assisted services in 7 prevention of mother-to-child transmissi project areas in Xinjiang, Yunnan and Guangxi provinces/autonomous regions. Information was collected during the perinatal period and viral load, CD4⁺T lymphocytes and drug resistance genes were detected at the same time. The multivariate logistic regression model was used to analyze the relationship between different factors and drug resistance in HIV-infected pregnant and postpartum women. Results: A total of 655 HIV-infected pregnant and postpartum women were included in this study. The incidence of drug resistance was 3.4% (22/655), all of whom were cross-drug resistant. The rate of low, moderate and high drug resistance was 2.1% (14/655), 1.2% (8/655) and 0.8% (5/655), respectively. The drug resistance rate in the people who had previously used antiviral drugs was 1.9% (8/418), and the drug resistance rate in the people who had not used drugs was 5.9% (14/237). The NNRTI drug resistance accounted for 2.8% (18/655) and the NRTI drug resistance rate was 2.5% (16/655). The multivariate logistic regression model showed that the risk of HIV resistance was lower in pregnant women who had previously used antiviral drugs (OR=0.32, 95%CI: 0.11-0.76). Conclusion: Strengthening the management of antiviral drug use and focusing on pregnant and postpartum women who have not previously used antiviral drugs can help reduce the occurrence of drug-resistant mutations. Personalized antiviral therapy should be considered to achieve viral inhibition effects in clinical practice.
Female ; Humans ; Pregnancy ; HIV Infections/drug therapy* ; Incidence ; China/epidemiology* ; Infectious Disease Transmission, Vertical/prevention & control* ; Postpartum Period ; Drug Resistance, Viral/genetics* ; Antiviral Agents/therapeutic use*

Objective: To analyze the incidence and related factors of drug resistance in HIV-infected pregnant and postpartum women in some areas of three western provinces of China from 2017 to 2019. Methods: From April 2017 to April 2019, face-to-face questionnaires and blood sample testing were conducted in all health care institutions providing maternal and perinatal care and midwifery-assisted services in 7 prevention of mother-to-child transmissi project areas in Xinjiang, Yunnan and Guangxi provinces/autonomous regions. Information was collected during the perinatal period and viral load, CD4⁺T lymphocytes and drug resistance genes were detected at the same time. The multivariate logistic regression model was used to analyze the relationship between different factors and drug resistance in HIV-infected pregnant and postpartum women. Results: A total of 655 HIV-infected pregnant and postpartum women were included in this study. The incidence of drug resistance was 3.4% (22/655), all of whom were cross-drug resistant. The rate of low, moderate and high drug resistance was 2.1% (14/655), 1.2% (8/655) and 0.8% (5/655), respectively. The drug resistance rate in the people who had previously used antiviral drugs was 1.9% (8/418), and the drug resistance rate in the people who had not used drugs was 5.9% (14/237). The NNRTI drug resistance accounted for 2.8% (18/655) and the NRTI drug resistance rate was 2.5% (16/655). The multivariate logistic regression model showed that the risk of HIV resistance was lower in pregnant women who had previously used antiviral drugs (OR=0.32, 95%CI: 0.11-0.76). Conclusion: Strengthening the management of antiviral drug use and focusing on pregnant and postpartum women who have not previously used antiviral drugs can help reduce the occurrence of drug-resistant mutations. Personalized antiviral therapy should be considered to achieve viral inhibition effects in clinical practice.
Female ; Humans ; Pregnancy ; HIV Infections/drug therapy* ; Incidence ; China/epidemiology* ; Infectious Disease Transmission, Vertical/prevention & control* ; Postpartum Period ; Drug Resistance, Viral/genetics* ; Antiviral Agents/therapeutic use*

Objective: To evaluate the efficacy and safety of HLA-haploidentical hematopoietic stem cell transplantation (allo-HSCT) for hepatitis-related aplastic anemia (HRAA) patients. Methods: Retrospective analysis was performed on hepatitis-associated aplastic anemia patients who received haplo-HSCT at our center between January 2012 and June 2022. October 30, 2022 was the final date of follow-up. Results: This study included 28 HRAA patients receiving allo-HSCT, including 18 males (64.3% ) and 10 females (35.7% ), with a median age of 25.5 (9-44) years. About 17 cases of severe aplastic anemia (SAA), 10 cases of very severe aplastic anemia (VSAA), and 1 case of transfusion-dependent aplastic anemia (TD-NSAA) were identified. Among 28 patients, 15 patients received haplo-HSCT, and 13 received MSD-HSCT. The 2-year overall survival (OS) rate, the 2-year failure-free survival (FFS) rate, the 2-year transplant-related mortality (TRM) rate, the 100-day grade Ⅱ-Ⅳ acute graft-versus-host disease (aGVHD) cumulative incidence rate, and the 2-year chronic graft-versus-host disease (cGVHD) cumulative incidence rate were 81.4%, 81.4% (95% CI 10.5% -20.6% ), 14.6% (95% CI 5.7% -34.3% ), 25.0% (95% CI 12.8% -45.4% ), and 4.2% (95% CI 0.6% -25.4% ), respectively. After transplantation, all patients had no significant liver function damage. Compared with the MSD-HSCT group, only the incidence of cytomegaloviremia was significantly higher in the haplo-HSCT group [60.0% (95% CI 35.2% -84.8% ) vs 7.7% (95% CI 0-22.2% ), P=0.004]. No statistically significant difference in the Epstein-Barr virus was found in the 2-year OS, 2-year FFS, 2-year TRM, and 100-day grade Ⅱ-Ⅳ aGVHD cumulative incidence rates and 2-year cGVHD cumulative incidence rate. Conclusion: Allo-HSCT is safe and effective for HRAA, and haplo-HSCT can be used as a safe and effective alternative for newly diagnosed HRAA patients who cannot obtain HLA-matched sibling donors.
Male ; Female ; Humans ; Adult ; Treatment Outcome ; Anemia, Aplastic/therapy* ; Retrospective Studies ; Epstein-Barr Virus Infections ; Herpesvirus 4, Human ; Graft vs Host Disease/etiology* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Hepatitis/etiology* ; Bronchiolitis Obliterans Syndrome ; Transplantation Conditioning

Objective: To analyze the epidemiological characteristics of pulmonary tuberculosis (PTB) in Fengtai District from 2011 to 2021. Methods: A retrospective study was conducted, the data of PTB patients in Fengtai District from 2011 to 2021 were collected in Chinese disease prevention and Control Information System, which included etiological classification, gender, age, occupation, onset time, demographic information etc. the epidemiological characteristics of reported PTB patients was analysis. Results: A total of 10 342 cases of PTB were reported from 2011 to 2021 in Fengtai District, with an average annual reported incidence rate of 42.87/ 100 000. The incidence rate was the highest in 2012(75.89/100 000), and significantly declined from 2013, which declined to 29.70/100 000 in 2017. It showed a slow rise from 2018 to 2021. The difference was statistically significant (χ²=1 471.77,P<0.001).There were 2 975 cases of etiologic positive PTB from 2011 to 2021, and 76 cases of Rifampicin-resistant PTB from 2017 to 2021. The ratio of male cases to female was 1.75, the average annual incidence rate of male (53.94/100 000) was higher, than female(31.57/100 000).(χ²=704.01,P<0.001). Among all age groups, 25-29 years group, 20-24 years group and 30-34 years group had the highest proportion, which were 1 506 cases (14.56%) , 1 292 cases (12.49%) and 1 024 cases (9.90%) respectively. The average annual incidence rate was the lowest in the group less than 10 years old (1.43/100 000), and the highest in the group 85 years old and over (195.20/100 000), the difference was statistically significant(χ²=3164.24, P<0.001). The top occupations from high to low were housework and unemployment (2 917 cases, 28.21%), retirees (2 308 cases, 22.32%), workers (1 047 cases, 10.12%), cadres and staff (950 cases, 9.19%), farmers (860 cases, 8.32%), business services (698 cases, 6.75%), teachers and students (455 cases, 4.40%). Conclusion: From 2011 to 2021, the incidence rate of PTB was decreased from 2012 to 2017, and slowly increased lately in Fengtai District. The epidemiological characteristics of PTB vary in different age and gender.
Adult ; Aged, 80 and over ; Beijing ; Child ; China/epidemiology* ; Female ; Humans ; Incidence ; Male ; Retrospective Studies ; Rifampin ; Tuberculosis, Pulmonary/prevention & control*

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases