[Clinical features of non-cirrhotic portal hypertension in patients with common variable immunodeficiency]

We wished to summarize the clinical features of common variable immunodeficiency (CVID) complicated by non-cirrhotic portal hypertension (NCPH) and to deepen our understanding of it. The case data of CVID complicated with NCPH admitted to Peking Union Medical College Hospital from January 1983 to May 2021 were analyzed retrospectively to summarize their clinical characteristics. Six patients with CVID combined with NCPH (three of each sex; 16-45 years) were assessed. Four patients had portal hypertension. All patients had anemia, splenomegaly, a normal serum level of albumin and transaminases, and possibly increased levels of alkaline phosphatase and gamma-glutamyl transpeptidase. Two patients were diagnosed with esophagogastric fundic varices by gastroscopy. Two patients underwent splenectomy (which improved hematologic abnormalities partially). Four patients had autoimmune disease. Two cases were diagnosed with nodular regenerative hyperplasia (NRH) upon liver biopsy. Six patients were administered intravenous immunoglobulin-G (0.4-0.6 g/kg bodyweight) once every 3-4 weeks as basic therapy. Often, CVID complicated with NCPH has: (1) The manifestations of portal hypertension as the primary symptom. (2) Autoimmune-related manifestations. Imaging can provide important diagnostic clues. The etiology may be related to hepatic NRH and splenomegaly due to recurrent infections.

[Epidemiological characteristics of pneumoconiosis deaths in a certain area from 1961 to 2020]

Objective: To investigate the epidemiological characteristics of pneumoconiosis deaths in Putuo District of Shanghai, and to provide evidence for prevention and management of pneumoconiosis in the future. Methods: In June 2021, the data of 263 patients with pneumoconiosis who died from January 1961 to December 2020 in Putuo District of Shanghai were retrospectively analyzed. Trend χ(2) test, analysis of variance and Spearman rank correlation methods were used to analyze the basic information, age of exposure to dust, promotion period, course of disease and direct cause of death of patients with pneumoconiosis. Results: Among the 263 cases of pneumoconiosis patients who died in Putuo District of Shanghai from 1961 to 2020, 260 cases (98.86%) were male. The main types of pneumoconiosis were foundry worker pneumoconiosis (53.23%, 140/263) and silicosis (43.73%, 115/263). The main types of pneumoconiosis were sand cleaner (36.50%, 96/263). The age of onset was (53.42±10.13) years old, the age of death was (76.14±9.12) years old, and the age of exposure to dust was (20.91±8.99) years. The duration of dust exposure was negatively correlated with the duration of disease (r(s)=-0.24, P<0.001). With the increase of pneumoconiosis stage, the mortality of silicosis and foundry worker pneumoconiosis also showed an increasing trend (χ(2)(trend)=4.22, 3.87, P=0.040, 0.049). 31.94% (84/263) of pneumoconiosis patients died directly from pneumoconiosis, ranking first among the direct causes of death. Conclusion: The death cases of pneumoconiosis in Putuo District of Shanghai are mainly foundry worker pneumoconiosis and silicosis, and pneumoconiosis is the main cause of death.

[Application of augmented reality and mixed reality navigation technology in laparoscopic limited right hepatectomy]

Objective: To investigate the application effect of augmented reality and mixed reality navigation technology in three-dimensional(3D) laparoscopic narrow right hepatectomy(LRH). Methods: A retrospective analysis was performed on the clinical data of 5 patients with hepatic malignancy admitted to the First Department of Hepatobiliary Surgery,Zhujiang Hospital,Southern Medical University from September 2020 to June 2021,all of whom were males,aged from 42 to 74 years.Preoperative evaluation was performed using the self-developed 3D abdominal medical image visualization system; if all the 5 patients were to receive right hemihepatectomy,the remnant liver volume would be insufficient,so LRH were planned.During the operation,the independently developed 3D laparoscopic augmented reality and mixed reality surgical navigation system was used to perform real-time multi-modal image fusion and interaction between the preoperative 3D model and 3D laparoscopic scene.Meanwhile,intraoperative ultrasound assisted indocyanine green fluorescence was used to determine the surgical path.In this way,the LRH under the guidance of augmented reality and mixed reality navigation was completed.The predicted liver resection volume was evaluated before surgery,actual resected liver volume,surgical indicators and postoperative complications were analyzed. Results: All the 5 patients completed LRH under the guidance of augmented reality and mixed reality navigation technology,with no conversion to laparotomy.The median operative time was 300 minutes(range:270 to 360 minutes),no intraoperative blood transfusion was performed,and the median postoperative hospital stay was 8 days(range:7 to 9 days).There were no perioperative deaths,or postoperative complications such as liver failure,bleeding,or biliary fistula. Conclusion: For patients who need to undergo LRH,the use of augmented and mixed reality navigation technology can safely and effectively guide the implementation of surgery,retain more functional liver volume,improve surgical safety,and reduce postoperative complications.

[Development and improvement of Chinese oral public health system]

The pandemic of COVID-19 in early 2020 is a big challenge to the mechanism of major epidemic prevention and control, the national public health management system, as well as medical and health resources in China. Going through the COVID-19 crisis, we should fully understand the problems and vulnerabilities of the current public health system in China, and it is imperative to deepen and strengthen the public health system which should be throughout whole life cycle and whole process. Oral cavity is the first portal of human body, while illness finds its way in by the mouth. Oral health is highly related to general health and quality of life. The outbreak has drawn the public's attention to the public health system. The establishment and improvement of the oral public health system with the concept of "public health with Chinese characteristics" should also attract people's attentions and thoughts. Furthermore it is urgent to recognize the importance of oral public health.

[Recommendations of diagnosis and treatment of gout in China]

Gout is a crystal associated arthritis caused by monosodium urate (MSU) accumulating in joint, and it belongs to metabolic rheumatic disease. In China, gout is common but it is insufficient for education of standardized diagnosis and treatment for gout. Based on the evidence and guidelines from China and other countries, Chinese gout Collaborative Research Group developed standardization of diagnosis and treatment of gout in China. The purpose is to standardize the methods for diagnosis of gout, treatment opportunity and strategies in order to reduce misdiagnosis, missed diagnosis and irreversible damage.

[The interpretation of 2018 updated European League Against Rheumatism evidence based recommendations for the diagnosis of gout]

With the improvement of people's living conditions and the prolonged lifespan, gout and hyperuricemia have increasingly become common chronic diseases in daily clinical practice for other physicians in addition to rheumatologists, even including general practitioners and primary care doctors. The European League Against Rheumatism (EULAR) firstly issued recommendations on gout diagnosis and management in 2006, which has been updated several times. Using a Delphi consensus approach, 2018 updated European League Against Rheumatism evidence-based recommendations for the diagnosis of gout finally formulated eight main recommendations, which was published online in June 2019. Not only does this edition emphasize the role of specialists, joint puncture or tophus aspirates and ultrasound in diagnosis, but also calls on all clinicians to pay more attention to risk factors of gout and associated comorbidities.

[The evaluation of training program "resident team leader in the Department of General Internal Medicine" at Peking Union Medical College Hospital]

Objective: To evaluate senior resident training program "resident team leader in the Department of General Internal Medicine" at Peking Union Medical College Hospital. Methods: We surveyed the residents or the fellows who had been selected as resident team leaders and received the training from October 2014 to September 2018 on their comments and suggestions. Results: Twenty-two rotated senior residents who were selected as team leaders in the Department of General Internal Medicine completed the survey. Almost all (21/22, 95.5%) of the respondents reported that they learnt more in general as team leaders by Visual Analog Scale (VAS). The mean VAS scores of clinical skills were 7.23±1.27, 7.86±1.32 in teaching abilities, 8.14±0.89 in leadership evaluation. Scales as chief resident assistants were 8.44±1.26. Sixteen respondents (72.7%) considered that pre-job training by attending doctors was necessary. Another 8 (36.4%) respondents addressed their demands on training of teaching skills. Conclusions: The senior resident training program "resident team leader in the Department of General Internal Medicine" improves the competency of rotated senior residents. It is a valuable pilot study on senior resident training and worthy of further application in other departments and hospitals.

[A questionnaire survey for gout management in physicians in Beijing]

Objective: To provide helpful continued medical education (CME) for physicians and improve gout treatment, we conducted a questionnaire survey to investigate physicians' knowledge in nine districts of Beijing. Methods: A questionnaire survey including ten gout-related questions was conducted among 298 physicians in Beijing. Demographic data and previous gout CME experience were collected. Chi-square test or Student's t test, univariate analysis and logistic regression analysis were used to evaluate the relevant factors of physicians' knowledge level. Results: A total of 250 valid copies were collected including 127 from community service centers (CSC), 123 from tertiary hospitals. The correct answer rate of gout etiology, pathogenesis and attack symptoms were over 70% in both groups. 45.5% (56/123) CSC doctors and 57.4% (66/115) tertiary doctors answered right drugs to control acute gout attack (P=0.067). Only 42.3% (52/123) in CSC and 53.4% (63/118) in hospitals chose allopurinol as a urate-lowering drug (ULT), while 46.3% (57/123) and 32.2% (38/118) doctors considered colchicine as a ULT drug (P=0.084) respectively. Near half doctors considered that gout patients should take long-term ULT [40.5% (51/126) vs. 57.6%(68/118)respectively, P=0.007]. Univariate analysis showed that CME training could improve gout-related knowledge in CRC doctors. Conclusion: Most CSC doctors generally understand basic knowledge of gout, while confusion of treatment is still significant. CME especially including standard gout treatment should be performed by doctors in tertiary hospitals.

[Clinical features of adult patients with chronic active Epstein-Barr virus infection]

Objective: To investigate the clinical features of adult-onset chronic active Epstein-Barr virus infection (CAEBV). Methods: A total of 21 adult patients with CAEBV who were admitted to the department of General Internal Medicine at Peking Union Medical College Hospital from January 2006 to January 2016 were retrospectively analyzed. Demographic data, disease duration, clinical manifestations, laboratory findings, treatments and prognosis were reviewed. Results: Eighteen females and 3 males were enrolled with a mean age of 39 years. The most common clinical manifestations included fever in 20 patients, splenomegaly in 20 patients, lymphadenopathy in 18 patients, and hepatomegaly in 10 patients, followed by laryngopharyngeal disorders in 6 patients, pleural effusion and peritoneal effusion each in 5 patients, rash in 4 patients, interstitial lung disease in 3 patients, gastrointestinal hemorrhage in 2 patients, and peripheral neuropathy and pulmonary hypertension each in 1 patient. Six patients were complicated with hemophagocytic lymphohis-tioncytosis(HLH) that developed 5-17 (mean: 9) months following CAEBV onset, all of whom experienced hyperpyrexia, pancytopenia, lymphadenopathy, splenomegaly, and liver dysfunction, 3 with hepatomegaly. Nineteen of the 21 patients had received steroid therapy including 10 combined with immunosuppressive agents, 11 with antiviral therapy, and 8 with intravenous immunoglobulin. Thirteen patients died, including 10 of multiple organ failure, (including 6 of HLH) 2 of severe pulmonary infection, and 1 of lymphoma. Six patients remained on follow-up, yet 2 were missing. Conclusions: CAEBV is expected with severe condition and poor prognosis, which is likely to be complicated with HLH. Clinical physicians should pay attention to adult patients with fever, hepatosplenomegaly and lymphadenopathy, which suggests possible CAEBV.

[An analysis of residents' self-evaluation and faculty-evaluation in internal medicine standardized residency training program using Milestones evaluation system]

Objective: To assess the value of internal medicine residency training program at Peking Union Medical College Hospital (PUMCH), and the feasibility of applying revised Milestones evaluation system. Methods: Postgraduate-year-one to four (PGY-1 to PGY-4) residents in PUMCH finished the revised Milestones evaluation scales in September 2017. Residents' self-evaluation and faculty-evaluation scores were calculated. Statistical analysis was conducted on the data. Results: A total of 207 residents were enrolled in this cross-sectional study. Both self and faculty scores showed an increasing trend in senior residents. PGY-1 residents were assessed during their first month of residency with scores of 4 points or higher, suggesting that residents have a high starting level. More strikingly, the mean score in PGY-4 was 7 points or higher, proving the career development of residency training program. There was no statistically significant difference between total self- and faculty-evaluation scores. Evaluation scores of learning ability and communication ability were lower in faculty group (t=-2.627, -4.279, all P<0.05). The scores in graduate students were lower than those in standardized training residents. Conclusions: The goal of national standardized residency training is to improve the quality of healthcare and residents' career development. The evaluation results would guide curriculum design and emphasize the importance and necessity of multi-level teaching. Self-evaluation contributes to the understanding of training objectives and personal cognition.

[Glycogen storage disease type Ⅰa: a rare cause of gout in adolescent and young adult patients]

Objective: To analyze the clinical features of secondary gout in glycogen storage disease type Ⅰa (GSD Ⅰa), so as to improve the awareness of this disease. Methods: The clinical features, laboratory findings, treatments and prognosis of 5 GSD Ⅰa patients with secondary gout who had been admitted to the Peking Union Medical College Hospital during 2006 to 2016 were collected and analyzed. GSD Ⅰa was confirmed by liver biopsy and genotyping. Results: Among the 5 patients (median age: 27 years), 3 were males and 2 were females. The mean age of gout onset was 17 ranging from 10 to 22 years old. The common manifestations of GSD included hepatomegaly since childhood, hypoglycemia, growth retardation, anemia, hyperlactacidemia and hyperlipidemia. All the 5 patients were complicated with gouty tophi and kidney stone. Gouty tophi and kidney stone were identified 3.8 years and 10.2 years after the first occurrence of articular symptoms, respectively. Renal damage occurred in 3 cases. All the patients underwent several therapeutic modalities including lifestyle intervention, allopurinol, and raw corn starch treatment. Conclusions: Determination of the presence of primary disease should be performed actively for young-onset gout with early occurrence of gouty tophi. GSD should be suspected if there exist clinical manifestations like hepatomegaly, recurrent hypoglycemia, growth retardation. Early management of hyperuricemia and gout in GSD patients is important to prevent complications and improve prognosis.

Deep Bleeder Acoustic Coagulation (DBAC)-part II: in vivo testing of a research prototype system

Background

Deep Bleeder Acoustic Coagulation (DBAC) is an ultrasound image-guided high-intensity focused ultrasound (HIFU) method proposed to automatically detect and localize (D&L) and treat deep, bleeding, combat wounds in the limbs of soldiers. A prototype DBAC system consisting of an applicator and control unit was developed for testing on animals. To enhance control, and thus safety, of the ultimate human DBAC autonomous product system, a thermal coagulation strategy that minimized cavitation, boiling, and non-linear behaviors was used.

Material and methods

The in vivo DBAC applicator design had four therapy tiles (Tx) and two 3D (volume) imaging probes (Ix) and was configured to be compatible with a porcine limb bleeder model developed in this research. The DBAC applicator was evaluated under quantitative test conditions (e.g., bleeder depths, flow rates, treatment time limits, and dose exposure time limits) in an in vivo study (final exam) comprising 12 bleeder treatments in three swine. To quantify blood flow rates, the “bleeder” targets were intact arterial branches, i.e., the superficial femoral artery (SFA) and a deep femoral artery (DFA). D&L identified, characterized, and targeted bleeders. The therapy sequence selected Tx arrays and determined the acoustic power and Tx beam steering, focus, and scan patterns. The user interface commands consisted of two buttons: “Start D&L” and “Start Therapy.” Targeting accuracy was assessed by necropsy and histologic exams and efficacy (vessel coagulative occlusion) by angiography and histology.

Results

The D&L process (Part I article, J Ther Ultrasound, 2015 (this issue)) executed fully in all cases in under 5 min and targeting evaluation showed 11 of 12 thermal lesions centered on the correct vessel subsection, with minimal damage to adjacent structures. The automated therapy sequence also executed properly, with select manual steps. Because the dose exposure time limit (t_dose ≤ 30 s) was associated with nonefficacious treatment, 60-s dosing and dual-dosing was also pursued. Thrombogenic evidence (blood clotting) and collagen denaturation (vessel shrinkage) were found in necropsy and histologically in all targeted SFAs. Acute SFA reductions in blood flow (20–30 %) were achieved in one subject, and one partial and one complete vessel occlusion were confirmed angiographically. The complete occlusion case was achieved with a dual dose (90 s total exposure) with focal intensity ≈500 W/cm² (spatial average, temporal average).

Conclusions

While not meeting all in vivo objectives, the overall performance of the DBAC applicator was positive. In particular, D&L automation workflow was verified during each of the tests, with processing times well under specified (10 min) limits, and all bleeder branches were detected and localized. Further, gross necropsy and tissue examination confirmed that the HIFU thermal lesions were coincident with the target vessel locations in over 90 % of the multi-array dosing treatments. The SFA/DFA bleeder models selected, and the protocols used, were the most suitable practical model options for the given DBAC anatomical and bleeder requirements. The animal models were imperfect in some challenging aspects, including requiring tissue-mimicking material (TMM) standoffs to achieve deep target depths, thereby introducing device-tissue motion, with resultant imaging artifacts. The model “bleeders” involved intact vessels, which are subject to less efficient heating and coagulation cascade behaviors than true puncture injuries.

Deep bleeder acoustic coagulation (DBAC)-Part I: development and in vitro testing of a research prototype cuff system

Background

Bleeding from limb injuries is a leading cause of death on the battlefield, with deep wounds being least accessible. High-intensity focused ultrasound (HIFU) has been shown capable of coagulation of bleeding (cautery). This paper describes the development and refereed in vitro evaluation of an ultrasound (US) research prototype deep bleeder acoustic coagulation (DBAC) cuff system for evaluating the potential of DBAC in the battlefield. The device had to meet quantitative performance metrics on automated operation, therapeutic heating, bleeder detection, targeting accuracy, operational time limits, and cuff weight over a range of limb sizes and bleeder depths. These metrics drove innovative approaches in image segmentation, bleeder detection, therapy transducers, beam targeting, and dose monitoring. A companion (Part II) paper discusses the in vivo performance testing of an animal-specific DBAC system.

Materials and methods

The cuff system employed 3D US imaging probes (“Ix”) for detection and localization (D&L) and targeting, with the bleeders being identified by automated spectral Doppler analysis of flow waveforms. Unique high-element-count therapeutic arrays (“Tx”) were developed, with the final cuff prototype having 21 Tx’s and 6 Ix’s. Spatial registration of Ix’s and Tx’s was done with a combination of image-registration, acoustic time-of-flight measurement, and tracking of the cuff shape via a fiber optic sensor. Acoustic radiation force impulse (ARFI) imaging or thermal strain imaging (TSI) at low-power doses were used to track the HIFU foci in closed-loop targeting. Recurrent neural network (RNN) acoustic thermometry guided closed-loop dosing. The cuff was tested on three phantom “limb” sizes: diameters = 25, 15, and 7.5 cm, with bleeder depths from 3.75 to 12.5 cm. “Integrated Phantoms” (IntP) were used for assessing D&L, closed-loop targeting, and closed-loop dosing. IntPs had surrogate arteries and bleeders, with blood-mimicking fluids moved by a pulsatile pump, and thermocouples (TCs) on the bleeders. Acoustic dosing was developed and tested using “HIFU Phantoms” having precisely located TCs, with end-of-dose target ∆T = 33–58 °C, and skin temperature ∆T ≤ 20 °C, being required.

Results

Most DBAC cuff performance requirements were met, including cuff weight, power delivery, targeting accuracy, skin temperature limit, and autonomous operation. The automated D&L completed in 9 of 15 tests (65 %), detecting the smallest (0.6 mm) bleeders, but it had difficulty with the lowest flow (3 cm/sec) bleeders, and in localizing bleeders in the smallest (7.5 cm) phantoms. D&L did not complete within the 9-min limit (results ranged 10–21 min). Closed-loop targeting converged in 20 of 31 tests (71 %), and closed-loop dosing power shut-off at preset ∆Ts was operational.

Summary and conclusion

The main performance objectives of the prototype DBAC cuff were met, however the designs required a number of challenging new technology developments. The novel Tx arrays exhibited high power with significant beam steering and focusing flexibility, while their integrated electronics enabled the required compact, lightweight configurability and simplified driving controls and cable/connector architecture. The compounded 3D imaging, combined with sophisticated software algorithms, enabled automated D&L and initial targeting and closed-loop targeting feedback via TSI. The development of RNN acoustic thermometry made possible feedback-controlled dosing. The lightweight architecture required significant design and fabrication effort to meet mechanical functionalities. Although not all target specifications were met, future engineering solutions addressing these performance deficiencies are proposed. Lastly, the program required very complex limb test phantoms and, while very challenging to develop, they performed well.

A waveform diversity method for optimizing 3-d power depositions generated by ultrasound phased arrays

A waveform-diversity-based approach for 3-D tumor heating is compared to spot scanning for hyperthermia applications. The waveform diversity method determines the excitation signals applied to the phased array elements and produces a beam pattern that closely matches the desired power distribution. The optimization algorithm solves the covariance matrix of the excitation signals through semidefinite programming subject to a series of quadratic cost functions and constraints on the control points. A numerical example simulates a 1444-element spherical-section phased array that delivers heat to a 3-cm-diameter spherical tumor located 12 cm from the array aperture, and the results show that waveform diversity combined with mode scanning increases the heated volume within the tumor while simultaneously decreasing normal tissue heating. Whereas standard single focus and multiple focus methods are often associated with unwanted intervening tissue heating, the waveform diversity method combined with mode scanning shifts energy away from intervening tissues where hotspots otherwise accumulate to improve temperature localization in deep-seated tumors.

The prevalence of dental erosion in preschool children in China

OBJECTIVE

To describe the prevalence of dental erosion and associated factors in preschool children in Guangxi and Hubei provinces of China.

METHODS

Dental examinations were carried out on 1949 children aged 3-5 years. Measurement of erosion was confined to primary maxillary incisors. The erosion index used was based upon the 1993 UK National Survey of Children's Dental Health. The children's general information as well as social background and dietary habits were collected based on a structured questionnaire.

RESULTS

A total of 112 children (5.7%) showed erosion on their maxillary incisors. Ninety-five (4.9%) was scored as being confined to enamel and 17 (0.9%) as erosion extending into dentine or pulp. There was a positive association between erosion and social class in terms of parental education. A significantly higher prevalence of erosion was observed in children whose parents had post-secondary education than those whose parents had secondary or lower level of education. There was also a correlation between the presence of dental erosion and intake of fruit drink from a feeding bottle or consumption of fruit drinks at bedtime.

CONCLUSION

Erosion is not a serious problem for dental heath in Chinese preschool children. The prevalence of erosion is associated with social and dietary factors in this sample of children.

Role of protein kinase A in GABAA receptor dysfunction in CA1 pyramidal cells following chronic benzodiazepine treatment

One-week treatment with the benzodiazepine (BZ) flurazepam (FZP), results in anticonvulsant tolerance, associated with reduced GABAA receptor (GABAR) subunit protein and miniature inhibitory post-synaptic current (mIPSC) amplitude in CA1 neurons of rat hippocampus. Because protein kinase A (PKA) has been shown to modulate GABAR function in CA1 pyramidal cells, the present study assessed whether GABAR dysfunction is associated with changes in PKA activity. Two days after 1-week FZP treatment, there were significant decreases in basal (- 30%) and total (- 25%) PKA activity, and a 40% reduction in PKA RIIbeta protein in the insoluble fraction of CA1 hippocampus. The soluble component of CA1 showed a significant increase in basal (100%) but not total PKA activity. Whole-cell recording in vitro showed a 50% reduction in mIPSC amplitude in CA1 pyramidal cells, with altered sensitivity to PKA modulators. Neurons from FZP-treated rats responded to 8-bromo-cAMP with a significant increase (31%) in mIPSC amplitude. Likewise, vasoactive intestinal polypeptide (VIP), an endogenous PKA activator, caused a significant 36% increase in mIPSC amplitude in FZP-treated cells. Neither agent had a significant effect on mIPSC amplitude in control cells. This study supports a role for PKA in GABAR dysfunction after chronic FZP treatment.

Role of bicarbonate ion in mediating decreased synaptic conductance in benzodiazepine tolerant hippocampal CA1 pyramidal neurons

Chronic flurazepam treatment substantially impairs the function of GABAergic synapses on hippocampal CA1 pyramidal cells. Previous findings included a significant decrease in the synaptic and unitary conductance of CA1 pyramidal neuron GABA(A) receptor channels and the appearance of a GABA(A)-receptor mediated depolarizing potential. To investigate the ionic basis of the decreased conductance, whole-cell voltage-clamp techniques were used to record evoked, GABA(A) receptor-mediated IPSCs carried by HCO(3)(-)-Cl(-) or Cl(-) alone. Hippocampal slices were prepared from rats administered flurazepam orally for 1 week, 2 days after ending drug treatment. Slices were superfused with HCO(3)(-)-aCSF or with HEPES-aCSF (without HCO(3)(-)) plus 50 microM APV and 10 microM DNQX. The micropipette contained 130 mM CsCl and 1 microM QX-314. GABA(A) receptors located on pyramidal cell somata or dendrites were activated monosynaptically by maximal stimulation of GABAergic terminals at the stratum oriens-pyramidale (SO-SP) or stratum lacunosum-molecular (S-L-M) border, respectively. In HCO(3)(-)-aCSF, there was a significant reduction in synaptic-conductance in flurazepam-treated neurons following both SO-SP (control: 1058 pS, flurazepam: 226 pS, P<0.01) and S-L-M (control 998 pS, flurazepam: 179 pS, P<0.01) stimulation, as well as the total charge transfer, indicating a decreased HCO(3)(-)-Cl(-) flux. In HEPES-aCSF, the synaptic conductance and total charge transfer, and thus Cl(-) flux, was unchanged in flurazepam-treated neurons (SO-SP: control 588 pS, flurazepam: 580 pS, P>0.05; S-L-M: control 595 pS, flurazepam: 527 pS, P>0.05). Taken together, these findings suggest that a reduction in HCO(3)(-) flux may play a prominent role in mediating the action of GABA and that a loss of HCO(3)(-) conductance may significantly contribute to impaired GABA(A) receptor function after chronic benzodiazepine treatment.

Antagonist-induced reversal of functional and structural measures of hippocampal benzodiazepine tolerance

One week oral flurazepam (FZP) administration in rats results in anticonvulsant tolerance in vivo, tolerance measured in vitro in hippocampal CA1 pyramidal cells, and regulation of hippocampal gamma-aminobutyric acid(A)-receptor subunit protein expression. A single injection (4 or 20 mg/kg i.p) of the benzodiazepine antagonist flumazenil (FLM) was given 1 day after FZP treatment, and tolerance and subunit protein expression were evaluated 1 day later. In vivo tolerance was measured by a reduced ability of the alpha(1)-subunit-selective agonist zolpidem to suppress pentylenetetrazole-induced seizures. This tolerance was reversed by 20 but not 4 mg/kg FLM. In in vitro hippocampal slices, there was tolerance to the effect of zolpidem to prolong the decay of pyramidal cell miniature inhibitory postsynaptic currents, which was reversed by FLM (4 mg/kg) pretreatment. A reduction in miniature inhibitory postsynaptic current amplitude ( approximately 50%) was also restored by FLM injection. [(3)H]Zolpidem binding measured 0, 2, and 7 days after FZP treatment was significantly decreased in the hippocampus and cortex at 0 days but not thereafter. Changes in alpha(1)- and beta(3)-subunit protein expression were examined via quantitative immunohistochemical techniques. alpha(1)-Subunit protein levels were down-regulated in the CA1 stratum oriens and beta subunit levels were up-regulated in the stratum oriens and stratum radiatum of the CA3 region. Chronic FZP effects on alpha(1)- and beta(3)-subunit protein levels were also reversed by prior FLM injection. FLM's effect on both functional and structural correlates of benzodiazepine tolerance suggests that each of these measures plays an interdependent role in mediating benzodiazepine tolerance.

Benzodiazepine-mediated regulation of alpha1, alpha2, beta1-3 and gamma2 GABA(A) receptor subunit proteins in the rat brain hippocampus and cortex

Prolonged flurazepam exposure regulates the expression of selected (alpha1, beta2, beta3) GABA(A) receptor subunit messenger RNAs in specific regions of the hippocampus and cortex with a time-course consistent with benzodiazepine tolerance both in vivo and in vitro. In this report, the immunostaining density of six specific GABA(A) receptor subunit (alpha1, beta2, beta1-3 and gamma2) antibodies was measured in the hippocampus and cortex, among other brain areas, in slide-mounted brain sections from flurazepam-treated and control rats using quantitative computer-assisted image analysis techniques. In parallel with the localized reduction in alpha1 and beta3 subunit messenger RNA expression detected in a previous study, relative alpha1 and beta3 subunit antibody immunostaining density was significantly decreased in flurazepam-treated rat hippocampal CA1, CA3 and dentate dendritic regions, and in specific cortical layers. Quantitative western blot analysis showed that beta3 subunit protein levels in crude homogenates of the hippocampal dentate region from flurazepam-treated rats, an area which showed fairly uniform decreases in beta3 subunit immunostaining (16-21%), were reduced to a similar degree (18%). The latter findings provide independent support that relative immunostaining density may provide an accurate estimate of protein levels. Consistent with the absence of the regulation of their respective messenger RNAs immediately after ending flurazepam administration, no changes in the density of alpha2, beta1 or beta2 subunit antibody immunostaining were found in any brain region. gamma2 subunit antibody staining was changed only in the dentate molecular layer. The selective changes in GABA(A) receptor subunit antibody immunostaining density in the hippocampus suggested that a change in the composition of GABA(A) receptors involving specific subunits (alpha1 and beta3) may be one mechanism underlying benzodiazepine anticonvulsant tolerance.

Long-term efficacy of plasma-derived hepatitis B vaccine: a 15-year follow-up study among Chinese children

To determine necessity and timing of booster of hepatitis B vaccine, we need to observe the duration of its protection. We report the results of a 15-year follow-up of a cohort of 649 children who participated a randomized, double blind, placebo-controlled trial on a plasma-derived hepatitis B vaccine in 1982. During the 15 years after vaccination, more vaccinated children had anti-HBs of 10 S/N ratios or over, compared with the controls, at all nine observations. At 15 years 50.0% (26/52) of the participants studied in the vaccinated group and 33.3% of the tested controls (18/54) retained anti-HBs levels of S/N ratios> or =10 (P < 0.09). However, since 5 years after vaccination, median S/N ratios of anti-HBs among the vaccinated children with detectable anti-HBs were lower than those of the controls except that detected at 15 years. 16.7% (9/54) of the tested children in the control group were HBsAg positive at 15 years after vaccination, in comparison with 1.9% (1/52) of the tested children in the vaccinated (P < 0.02). 28 chronic HBsAg carriers were identified in the control cohort over the 15 years, whereas only 1 case was noted in the vaccinated group (8.2% vs. 0.3%, P < 0.00001), corresponding to an efficacy of 96%.

Benzodiazepine tolerance at GABAergic synapses on hippocampal CA1 pyramidal cells

Modulation of GABA function following 1 week oral administration of flurazepam (FZP) was investigated in chloride-loaded, rat hippocampal CA1 pyramidal neurons. Rats were sacrificed 2 or 7 days after ending drug treatment, when anticonvulsant tolerance was present or absent in vivo, respectively. Spontaneous (s)IPSCs and miniature (m)IPSCs were recorded using whole-cell voltage-clamp techniques. s/mIPSCs were bicuculline-sensitive, voltage-dependent, and reversed their polarity at 0 mV, the predicted E(Cl-). Comparisons of s/mIPSCs between FZP-treated and control groups were made at Vh = -90, -70, and -50 mV. The frequency of sIPSCs, but not mIPSCs, was significantly decreased in FZP-treated neurons 2 days, but not 7 days, after FZP treatment, suggesting a decrease in interneuron activity. These conclusions were supported by the negative findings of additional studies of [3H]GABA release from hippocampal slices and [3H]GABA uptake from hippocampal synaptosomes. The lack of change in the paired-pulse depression of GABA(B)-mediated IPSPs suggested that autoreceptor function was also not impaired following chronic FZP treatment. A large reduction in both sIPSC and mIPSC amplitude (60%) in FZP-treated neurons, the absence of mIPSCs in one-third of FZP-treated cells, and a measurable reduction in synaptic and unitary conductance confirmed that postsynaptic GABA(A) receptor function was profoundly impaired in FZP-treated CA1 neurons. Zolpidem, an alpha1-selective benzodiazepine receptor ligand, enhanced mIPSC amplitude and decay, but its ability to prolong mIPSC decay was reduced in FZP-treated neurons. Several pre- and postsynaptic changes at GABAergic synapses on CA1 pyramidal cells might be related to the decreased tonic GABA inhibition in FZP-treated CA1 neurons associated with the expression of benzodiazepine anticonvulsant tolerance.

Patterns and determinants of use of antibiotics for acute respiratory tract infection in children in China

BACKGROUND

Use of antibiotics for acute respiratory infection (ARI) of presumed viral etiology is a worldwide problem. The World Health Organization (WHO) has provided guidelines for diagnosis and treatment of ARI for developing countries.

METHODS

Specially trained observers applied the WHO criteria to study the diagnosis and treatment of ARI given by 100 randomly selected health care workers (HCWs) in a rural county in China. A total of 750 cases of ARI were evaluated.

RESULTS

Before the parents sought medical care, 47% of children in the county hospitals, 25% of those in the townships and 18% of those in the villages had already received antibiotics, available without prescription. Among the HCWs antibiotic abuse (antibiotics for presumably viral disease) was detected in the treatment of 97% of cases, and severe abuse (such as prescription of two incompatible antibiotics) was detected in 37%. Most (197 of 200) patients with bacterial disease received antibiotics, but inappropriate antibiotic treatment (dose or type) was observed in 63% of these cases. HCWs with university training and those with higher test scores on knowledge and attitude prescribed antibiotics more judiciously than those lacking those attributes.

CONCLUSIONS

Abuse of antibiotics for ARI is a serious and costly problem in rural China, potentially leading to widespread antibiotic resistance. Educating HCWs in the management of ARI and proper use of antibiotics has high priority in China.

[Effects of tripchlorolide (T4) of Tripterygium Wilfordii Hook on the production of immunoglobulins by peripheral blood mononuclear cells and by synovial cells of rheumatoid arthritis patients in vitro]

Tripchlorolide(T4) is an active ingredient recently isolated from Tripterygium Wilfordii Hook. The in vitro effects of T4 on the peripheral blood mononuclear cells(PBMC) of healthy persons(n = 10), the digested single synovium cells(DSSC) (n = 3) and PBMC(n = 6) from RA patients on production of immunoglobulins (Ig) were studied using Elisa method. The results showed that T4 at concentrations from 5 ng.ml-1 to 35 ng.ml-1 significantly reduced the production of Ig by PWM-stimulated PBMC of healthy persons in a dose dependent manner. At concentration of 25 ng.ml-1, T4 also reduced the Ig secretion of RA-PBMC and DSSC. It is hoped that T4 would be an encouraging new drug of herbal nature for the treatment of RA.

Approximation properties of fuzzy systems generated by the min inference

This paper discusses the approximation properties of fuzzy systems generated by the min inference. Firstly, the paper analyzes the properties of fuzzy basis functions (FBFs); Then based on the properties of FBPs, several basic approximation properties concerning approximation mechanisms, uniform approximation bounds, uniform convergency, and universal approximation are obtained. Further, the similarity and difference between the fuzzy systems generated by the product inference and by the min inference are discussed.

A relationship between membership functions and approximation accuracy in fuzzy systems

This paper presents a relationship between membership functions and approximation accuracy in fuzzy systems. This relationship suggests an idea to design membership functions such that the approximation accuracy of fuzzy systems is improved.

Hepatolithiasis in East Asia: comparison between Japan and China

The incidence of hepatolithiasis is high throughout East Asia compared with the West, but the marked difference in the relative proportion of hepatolithiasis to all cholelithiasis cases exists even among countries of similar ethnic backgrounds. A retrospective study of cases was conducted in two areas in China with the aim of clarifying the presence of such regional difference in China itself. The relative proportion of hepatolithiasis was 21.2% in Shenyang, 9.2% in Beijing and 4.1% in Fukuoka, Japan. A significant difference in the location of stones was also found between Shenyang, Beijing and Fukuoka. Intra- and extrahepatic hepatolithiasis in all hepatolithiasis cases was 95% in Shenyang and 75% in Beijing. Involvement of both hepatic lobes was found in 73% in Shenyang and less than 60% in the other two, suggesting that hepatolithiasis of the old form or of an advanced stage still lingers in Shenyang. In conclusion, regional differences in the proportion and the type of hepatolithiasis exist in China itself, as well as in the Chinese population in Taiwan, Hong Kong and Singapore, as previously reported. The possible contribution of environmental factors to the occurrence of hepatolithiasis is again emphasized.

Insulinoma: 31 years of tumor localization and excision

This report is based on 31 years of experience with 116 cases of hyperinsulinism. Six cases had hypertrophy of the islets of Langerhans, 3 had widespead metastasis from malignant insulinomas, and 107 were benign adenoma cases. An immunoreactive insulin to glucose ratio of 0.3 of the peripheral venous blood before operation is of great value in diagnosing hyperinsulinism. Intraoperatively, immunoreactive insulin assay of the portal blood (IRI) is very valuable in determining if an insulinoma remains. The dividing line is 100 microU.ml-1. In localizing the tumor, "differential" PTPC is important before operation. During the operation, fine needle aspiration cytology may assist in ascertaining if the palpable tumor is an insulinoma. Multiple fine needle aspiration cytology examinations can sometimes reveal an insulinoma in an indurated pancreas. Portal vein blood IRI and blood sugar assays may serve to confirm if removal of the insulinoma is complete. Removal of the insulinoma controls hypoglycemia satisfactorily, but the brain damage incurred by prolonged hypoglycemia cannot be significantly altered. Removal of the tumor should be by enucleation, and the raw surface of the pancreas should be drained not sutured.