[Functional analysis of laparoscopic intracorporeal Xing's neobladder in long-term follow-up].

Evaluation of neobladder function in patients with long-term survival and no recurrence after laparoscopic radical cystectomy and intracorporeal Xing's neobladder. The clinical data of laparoscopic radical cystectomy and intracorporeal Xing's neobladder in long-term survival patients with bladder cancer treated in Beijing Chaoyang Hospital from July 2013 to July 2018 were analyzed retrospectively. All 17 patients underwent the surgery by the same surgical team, including 15 males and 2 females, whose mean age at the time of operation was (55.9±7.6) years. Thepostoperative urinary function and renal function were summarized. All operations were successfully completed. The mean operative time was (340±62) min. All patients were followed up for a long time, with a median follow-up time of 80(70, 96) months, Urinary continence was achieved in 17 (100%)casesduring the day and 13 (76.5%) cases at night, with a median bladder volume of 350 (200, 400) ml. All patients had good urinary control after surgery, and no hydronephrosis or creatinine increase was found in reexamination.After the application of Xing's neobladder operation, the patient maintained acceptable urinary control status after the operation, and the long-term follow-up effect was satisfactory.

[Clinical experiences of laparoscopic radical cystectomy and urinary diversion in the elderly patients with bladder cancer].

Objective: To optimize the surgical procedures of laparoscopic radical cystectomy and urinary diversion for the elderly patients with bladder cancer, generalize operating technique, summarize clinical experiences. Methods: From July 2004 to October 2016, laparoscopic radical cystectomy (LRC) and urinary diversion was performed in 68 elderly patients (≥75 years old) diagnosed with bladder cancer in urology department of Beijing Chaoyang Hospital, Capital Medical University, and the relevant clinical and follow-up data were retrospectively reviewed. All the patients were pathologically diagnosed and their perioperative data, postoperative pathological results, postoperative complications and follow-up outcomes were recorded and analyzed. Results: Among 68 elderly patients with bladder cancer, fifty patients were male and 18 were female, the age of whom were (79±4) (range 75 to 91) years old. The Charlson comorbidity index (CCI) score was 6±1 (range 5 to 7). All the 68 operations were successfully performed without conversion to open surgery. There were 26 cases receiving cutaneous ureterostomy, 34 cases receiving ileal conduit (intracorporeal for 16 cases and extracorporeal for 18 cases) and 8 cases receiving orthotopic ileal neobladder (intracorporeal for 4 cases and extracorporeal for 4 cases; Xing's technique for 4 cases, T-Pouch for 2 cases and Studer-Pouch for 2 cases) respectively, and the operation time of these three groups were (221±47) min, (315±70) min and (358±90) min respectively, the estimated blood loss were 100 (87, 200)ml, 300 (250, 500) ml and 250 (113, 725) ml respectively, the time of intake of liquid diet were 3 (2, 4) d, 6 (5, 7) d and 9 (5, 12) d respectively, and the postoperative hospital stay were (12±6) d, (24±11) d, and (27±11) d respectively. Postoperative pathological results showed urothelial carcinoma in 64 patients, squamous cell carcinoma in 2 patients and adenocarcinoma in 2 patients. Sixty patients received laparoscopic pelvic lymphadenectomy and the number of dissected lymph nodes was 17.1±7.0. There were 46 cases with T stage greater than or equal to T2 (46/68, 67.6%), 4 cases of low grade (4/68, 5.9%) and 60 cases of high grade (60/68, 88.2%). All the early postoperative (within 30 days after the operation) complications were grade Ⅰ-Ⅱ mainly manifested as fever, pain and infection that could get better with symptomatic treatment, and the incidence rate were 30.8% for cutaneous ureterostomy, 29.4% for ileal conduit and 37.5% for orthotopic ileal neobladder. The patients were followed up for a median period of 93.5 months without obvious hydronephrosis and impaired renal function. The 5-year cancer specific survival rate and overall survival rate were 57% and 50% respectively. There was significant difference between the preoperative and postoperative QOL (quality of life) score (56.0±10.0 and 47.4±5.8 respectively, P<0.05) which indicated that the patients' postoperative quality of life was greatly improved. Conclusions: Laparoscopic radical cystectomy and urinary diversion for the elderly patients with bladder cancer is safe and feasible, and owns great therapeutic value.

Salmonella induce autophagy in melanoma by the downregulation of AKT/mTOR pathway.

Salmonella have been demonstrated to inhibit tumor growth. However, the mechanism of Salmonella-induced tumor cell death is less defined. Autophagy is a cellular process that mediates the degradation of long-lived proteins and unwanted organelles in the cytosol. Tumor cells frequently display lower levels of basal autophagic activity than their normal counterparts and fail to increase autophagic activity in response to stresses. Autophagy is involved in the cell defense elimination of bacteria. The signaling pathways leading to activation of Salmonella-induced autophagy in tumor cells remain to be elucidated. We used autophagy inhibitor (3-Methyladenine) and apoptosis inhibitor (Z-VAD-FMK) to demonstrate that Salmonella may induce cell death via apoptosis and autophagic pathway. Meanwhile, we suggested that Salmonella induce autophagy in a dose- and time-dependent manner. The autophagic markers were increased after tumor cell infected with Salmonella. In addition, the protein express levels of phosph-protein kinase B (P-AKT), phosph-mammalian targets of rapamycin (P-mTOR), phosph-p70 ribosomal s6 kinase (P-p70s6K) in tumor cells were decreased by western analysis after Salmonella infection. In conclusion, our results point out that Salmonella induce the autophagic signaling pathway via downregulation of AKT/mTOR pathway. Herein, our findings that Salmonella in controlling tumor growth may induce autophagic signal pathway.

[Analysis on transmission chain of a cluster epidemic of COVID-19, Nanchang].

Objective: Based on an investigation of an outbreak of COVID-19 in Nanchang, to understand the transmission process, analyze the infectivity of the cases in incubation period and asymptomatic carrier, and evaluate the transmission risks in different exposures. Methods: Case investigation was based on the traditional epidemiological survey, combined with analysis based on big data about population movement trajectories. Transmission chain was identified to indicate transmission relationship. Results: A total of 27 cases were found in this cluster epidemic, including 25 confirmed cases, 1 suspected case (index case) and 1 asymptomatic carrier. A total of 347 close contacts were found. The secondary attack rate was 7.2% (25/347). The infection rates in close contacts of the first, second, third and fourth generation cases were 52.6% (10/19), 6.1% (13/213), 2.3% (2/88) and 0.0% (0/27), respectively. Asymptomatic carrier caused household transmission. The infection rates in close contacts after having meals, sharing rooms/beds, having work contacts, having neighbor contacts, having same time medical services or sharing wards and sharing vehicles with the patients were 10.6%(17/160), 10.0%(20/201), 5.3%(5/94), 0.0%(0/30), 0.0%(0/18) and 0.0%(0/17), respectively. Conclusions: The infection source of this cluster epidemic was a suspected case from Wuhan. Analysis based on big data about population movement trajectories can help to search the cases and close contacts accurately. The proposed epidemic prevention and control measures based on this investigation were effective.

Beneficial effect of Rhodopseudomonas palustris on in vitro rumen digestion and fermentation.

As a member of photosynthetic bacteria, Rhodopseudomonas palustris, which has extraordinary metabolic versatility, has been applied as one of potential probiotics in feed industry. To explore whether R. palustris can increase rumen microbial viability and thus improve microbial fermentation, a 2×5 factorial experiment was conducted to evaluate the effect of R. palustris at dose rates of 0, 1.3, 2.6, 3.9, 5.2×106 cfu/ml on ruminal fermentation of two representative total mixed rations (HY, a ration for high-yield (>32 kg/d) lactating cows; LY, a ration for low-yield (<25 kg/d) lactating cows). After a 48 h in vitro rumen incubation, both rations resulted in different fermentation characteristics. The HY in comparison with LY group presented greater in vitro dry matter disappearance (IVDMD), cumulative gas production (GP48) and total volatile fatty acids (VFA, P<0.01). Increasing R. palustris addition linearly increased IVDMD (P<0.01) and GP48 (P<0.05), and the IVDMD increment in response to R. palustris addition was greater in LY than HY group (6.4% vs 1.4%). Meanwhile, increasing R. palustris addition also linearly enhanced microbial protein synthesis and increased total VFA production (P<0.01), especially in LY group (up to 21.5% and 24.5% respectively). Unchanged acetate and declined propionate in molar percentage were observed in response to the R. palustris addition. Furthermore, increasing R. palustris addition altered fermentation gas composition in which molar O2 proportion in headspace of fermentation system was linearly reduced by 46.1% in LY and 32.9% in HY group, respectively (P<0.01), and methane production in both ration groups was enhanced by 1.9-4.1% (P=0.02). In summary, the R. palustris addition exhibited high potential for promoting the growth of rumen microorganism and enhancing microbial fermentation towards non-glucogenic energy supply by maintaining an anaerobic environment to microbe equilibrium.

The possible role of arterial radial vibration in heart rate and blood pressure matching.

MOTIVATION: This study tests if the 'oscillating spring' analogy for the radial vibration of the arterial wall can help to describe the relationship between the heart rate (HR), the blood pressure (BP), and properties of the arterial wall when different types of stimulation are applied on the cardiovascular system. It may help to suggest a possible role for arterial radial vibration in the association between the arterial stiffening and hypertension. METHODS: Either mechanical stimulation was applied (0.5-mmHg pressure variation) to Wistar rats by at near-HR frequency (group A) or administered Propranolol (2mg/kg i.p.; group B), and measured HR and BP simultaneously. RESULTS: In both groups, HR and BP were noted to change in the same direction (r2 = 0.72 and 0.62, respectively; p both < 0.05 by F-test). ANCOVA was performed on these two regression lines, and it was found that there was no significant difference between them (p > 0.3). CONCLUSION: In both groups, changes in haemodynamic parameters can be explained by the 'oscillating spring' analogy for the radial vibration of the arterial wall. This illustrates that, when facing various stimulations, it may be an important regulatory mechanism for the heart and the arteries to restore their frequency-matching condition in order to improve the arterial transmission efficiency. Paying more attention to the radial movement of the wall may therefore help to suggest a novel explanation of the mechanism that underlies the bidirectional relation between hypertension and arterial stiffening.

Evaluating microcirculation by pulsatile laser Doppler signal.

Laser Doppler flowmetry (LDF) is a popular method for monitoring the microcirculation, but it does not provide absolute measurements. Instead, the mean flux response or energy distribution in the frequency domain is generally compared before and after stimulus. Using the heartbeat as a trigger, we investigated whether the relation between pressure and flux can be used to discriminate different microcirculatory conditions. We propose the following three pulsatile indices for evaluating the microcirculation condition from the normalized pressure and flux segment with a synchronized-averaging method: peak delay time (PDT), pressure rise time and flux rise time (FRT). The abdominal aortic blood pressure and renal cortex flux (RCF) signals were measured in spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). The mean value of the RCF did not differ between SHR and WKY. However, the PDT was longer in SHR (87.14 +/- 5.54 ms, mean +/- SD) than in WKY (76.92 +/- 2.62 ms; p < 0.001). The FRT was also longer in SHR (66.56 +/- 1.98 ms) than in WKY (58.02 +/- 1.77 ms; p < 0.001). We propose that a new dimension for comparing the LDF signals, which the results from the present study show, can be used to discriminate RCF signals that cannot be discriminated using traditional methods.

Effects of whole-body mechanical stimulation at double the heart rate on the blood pressure waveform in rats.

The effects of mechanical stimulation on hemodynamics, such as due to mechanotransduction in vascular endothelial cells, have been widely discussed recently. We previously proposed a resonance model in which the arterial system is treated as a pressure-transmitting system, and suggested that the application of external mechanical stimulation with frequencies near the heart rate (HR) or harmonics thereof can be sensed by the arterial system and induce hemodynamic changes. In this study, we monitored the effects of external mechanical stimulation at a frequency of double the HR on BPW (blood pressure waveform), HRV (HR variability) and BPHV (blood-pressure-harmonics variability) in rats. A motor beating a waterbed mattress was used to generate pressure variations of 0.5 mmHg to apply onto the rats. The experiments were performed on three groups of rats with different beating frequencies: (A) double the HR, (B) 5% deviation from double the HR and (C) 1.5 times the HR. The experimental procedure was a 15 min control period followed by application of the mechanical stimulation for 15 min and further recording for 15 min (OFF period). During the OFF period, the amplitude of the second harmonic in the BPW significantly increased by >5% in group A with decreased HRV and BPHV. The second harmonic increased less in group B, and decreased in group C. The increase in the second-harmonic amplitude in group A may be due to the filtering properties of the renal arterial structure. This mechanism could be used to improve the local blood supply into the kidneys, and hence provide a new treatment modality for some important diseases, such as renal hypertension or nephrosis.

Growth under elevated air temperature alters secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robiniapseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds, and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites.

Stability and folding of the tumour suppressor protein p16.

The tumour suppressor p16 is a member of the INK4 family of inhibi tors of the cyclin D-dependent kinases, CDK4 and CDK6, that are involved in the key growth control pathway of the eukaryotic cell cycle. The 156 amino acid residue protein is composed of four ankyrin repeats (a helix-turn-helix motif) that stack linearly as two four-helix bundles resulting in a non-globular, elongated molecule. The thermodynamic and kinetic properties of the folding of p16 are unusual. The protein has a very low free energy of unfolding, Delta GH-2O/D-N, of 3.1 kcal mol-1 at 25 degreesC. The rate-determining transition state of folding/unfolding is very compact (89% as compact as the native state). The other unusual feature is the very rapid rate of unfolding in the absence of denaturant of 0.8 s-1 at 25 degreesC. Thus, p16 has both thermodynamic and kinetic instability. These features may be essential for the regulatory function of the INK4 proteins and of other ankyrin-repeat-containing proteins that mediate a wide range of protein-protein interactions. The mechanisms of inactivation of p16 by eight cancer-associated mutations were dissected using a systematic method designed to probe the integrity of the secondary structure and the global fold. The structure and folding of p16 appear to be highly vulnerable to single point mutations, probably as a result of the protein's low stability. This vulnerability provides one explanation for the striking frequency of p16 mutations in tumours and in immortalised cell lines.

Genetic variation within human immunodeficiency viruses generates rapid changes in tropism, virulence, and transmission.

The human immunodeficiency viruses (HIV-1) undergo high rates of variation. Only a few point mutations in the envelope gene are required to switch the tropism of HIV-1 from a growth preference for monocytes to lymphocytes or to acquire lytic properties for rapid killing of infected T4 lymphocytes. Since heterosexual transmission efficiency is high for HIV-1's that are most prevalent in Africa or Asia, but low for HIV-1 B, which dominates in the US and western Europe, we asked whether African and Asian viruses had a particular tropism for cells of the reproductive tract. Langerhans' cells (LC), showed only minimal susceptibility to infection with HIV-1B from the US, but substantially greater sensitivity for infections by HIV-1 E and HIV-1 C, subtypes that predominate in Asia and Africa.

Raising harmonic variation of arterial pulse in dying rats.

Our previous study revealed that the coefficient of variation of harmonic magnitude (HCV) of radial arterial pulse was significantly raised before the death of cancer patients. In this study, we recorded the caudate arterial pulse of 24 Sprague-Dawley rats that had a fatal dose of urethane injected into their abdomens. Twenty rats were dead within 3 hours after the injection and four survived. We defined the last 100 minutes of each rat's life as the dying process. During the dying process, we found that both the systolic blood pressure and diastolic blood pressure dropped steeply during the last 5 minutes. However, all HCVs, except HCV1, climbed steeply before the last 5 minutes. The HCV1 of the dying rats was significantly higher than that of rats that survived, starting from the first minute (P < 0.01). The HCV2 of the dying rats was significantly higher than that of the survived rats starting from the 52nd minute (P < 0.05). The HCV3 and HCV4 of the dying rats were significantly higher than those of the survived rats until the 70th minute and the 80th minute, respectively (P < 0.05). Furthermore, HCV2-HCV4 proceeded with the dying process and increased gradually. We concluded that HCVs, which failed first in the high-frequency components and then in the low-frequency components, could provide physicians with earlier information to prevent the coming failure of circulatory system, and could reflect quantitatively pathological severity and predict patient outcome. The specific Fourier components in the pulse provide more physiological information than systolic and diastolic blood pressures.

Specific frequency properties of renal and superior mesenteric arterial beds in rats.

In order to investigate the effects of arterial beds on pressure waveforms in arteries, the pressure waves observed in the rat tail artery were resolved into their Fourier moduli before and during ligation of the left renal artery and the superior mesenteric artery. Consistently different patterns of waveform changes in the tail artery were seen on occlusion of these vessels. Ligation of the renal artery reduced, and of the superior mesenteric artery increased, the pressure harmonics over most of the spectra. These results imply that to study the changes in the pressure contours as the observation point is moved downstream, one may have to account separately for the contributions of individual arterial beds. This is relevant in considering the degree to which it is appropriate for data to be amalgamated in models of the systemic arterial bed.

A space-resolved fluorometer and its application to immunoassay.

A metal surface has been added into a fluorometer to reflect the excited light and to reduce the light scattering. Due to the total separation of the fluorescent signal and the noise by directing them into different spaces, the resolution could be improved by several orders of magnitude. The same metal surface could also be used for immunoassays. The detection of alpha-fetoprotein in normal rat serum and human standard serum are given as examples. The results indicate that the apparatus and the method have significant advantages.

Interaction between HIV type 1 glycoprotein 120 and CXCR4 coreceptor involves a highly conserved arginine residue in hypervariable region 3.

Several seven-transmembrane chemokine receptors are known to function as entry coreceptors for human immunodeficiency virus type 1. CCR5 and CXCR4 are the major coreceptors for non-syncytium-inducing (NSI) and syncytium-inducing (SI) viruses, respectively. During the natural course of infection, the emergence of variants with a phenotypic transition from NSI to SI and rapid disease progression is associated with expanded coreceptor usage to CXCR4. Characteristic amino acids at several positions in the hypervariable region 3 (V3) of gp120 have been linked to CXCR4 utilization. Previously, we reported that a highly conserved arginine residue of V3 played an important role in CCR5 utilization. In this study, the possible involvement of the same arginine residue in CXCR4 utilization was investigated. Amino acid substitutions introduced to this arginine on R5X4 viruses were found to have a significant effect on their utilization of CXCR4. These results, taken together with those reported previously, suggest that this highly conserved arginine may contribute to the functional convergence of chemokine coreceptor utilization by human immunodeficiency viruses and may represent a unique target for future antiviral design.

Molecular biology of human immunodeficiency virus type 1.

Since the discovery of human immunodeficiency virus (HIV) as the etiologic agent of acquired immune deficiency syndrome (AIDS) more than a decade ago, tremendous progress has been made in various aspects of this virus and its interplay with the host immune system. The advent of potent combination therapy has made it possible to achieve effective and durable control of HIV-1 replication in vivo, yet the persistence of the latent reservoirs pose a new challenge. The recent identifications of several cellular proteins interacting with different viral gene products have not only shed new insights into our understanding of the HIV-1 and the host cell biology, but also provided the bases for developing novel strategies to block HIV-1 replication. It is from this perspective that we review the current understanding of the molecular mechanisms governing the HIV-1 life cycle.

Effect of length on the fundamental resonance frequency of arterial models having radial dilatation.

The pressure wave moving along an elastic artery filled with blood was examined as a moving Windkessel having a natural oscillation angular frequency nu 0 and a damping coefficient b. The radial directional motion for an element of the wall segment and the adherent fluid was considered. This equation was solved with conditions at both ends of an artery of length L. An external impulse force was applied at one end and a static pressure Po at the other. Analytic solution allowed only certain oscillation modes of resonance frequencies fn, where fn2 = a + cnL-2 with [formula: see text] and V infinity is the high frequency phase velocity. The relationship between f0 and L was examined experimentally for tubes constructed of latex, rubber, or dissected aorta. The effect of raising the static pressure P0 or increasing the tension in the tube was consistent with the prediction. The hypertension that accompanies an augmentation in arterial wall and the association between the heart rate and the mean blood pressure were discussed.

Validation of fermentation processes.

The ability to prepare consistent biopharmaceutical products depends extensively on possession of banked and characterized cell substrates and on development of production processes which can be validated. While the attributes that define cell characterization have been extensively detailed by ICH and the regulatory agencies in the past decade, little has been specified regarding process validation for biological processes. The extent to which validation concepts can be applied to biological processes varies depending on the nature of the process, the nature of the product, and the level of knowledge regarding the relationship between process parameters and product quality. Expectations concerning the rigour of the validation programme should be adjusted accordingly. There is no single approach that is appropriate for all processes and products. At a minimum, there should be an attempt to define which process parameters are critical, and to focus the attention of validation efforts on these parameters.

Structural features of the Clostridium thermocellum cellulase SS gene.

The Clostridium thermocellum cellulase SS is a subunit of the extracellular cellulase complex (cellulosome). It has previously been shown that SS, hydrolyzes crystalline cellulose synergistically with another subunit, SL. To study this synergism further, the authors cloned the gene coding for SS (celS) and compared its sequence to other known cel genes. The celS, although unique in its DNA sequence, has many structural features similar to those found in other cel genes. These features include a ribosome biding site, signal peptide sequence, the existence of a conserved reiterated amino acid sequence, and a palindromic structure downstream from its open reading frame.

Alterations of pulse by Chinese herb medicine.

Rats were injected with the crude extract of Chinese herbs, Rhizoma Coptidis, Radix Bupleuri and Cinnamomum cassia Blume. The pulse of the tail artery were examined. The results indicated that each drug had a specific effect on the Fourier components of the pulse.