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61.

Background:

Laparoscopic and robotic surgery is widely practiced in modern medicine. The operative procedure is not complete until the port sites are closed with a fascial suture. We report a simple new technique that is easy, cost-effective, and quick to apply using 2 S-retractors for suture placement under direct visualization to secure the abdominal wall fascia and peritoneum.

Materials and Methods:

As a prospective consecutive case series, this technique was used for fascial closure after laparoscopy ports > 8 mm using 2 S-retractors. One S-retractor is used as a barrier protecting the contents of the abdominal cavity, reducing the risk of visceral injuries. The second S-retractor allows us to directly visualize the different layers, exposing the needle tip during its course through the fascia.

Results:

This method was used in 100 patients with no intraoperative incidents, additional operative time, or need to access costly instruments. Currently, this technique is also used by many surgeons in our institution without any difficulty. No bowel injuries or port-site hernias were reported during a mean follow-up of 6 wk postoperation and 12-mo annual follow-up.

Conclusion:

The procedure is simple, easy, cost-effective, and quick to apply.  相似文献   
62.
Background contextVertebral hemangiomata are ubiquitous bone tumors. Often multiple, they are generally benign in nature and slow growing. They typically have a predictable radiographic appearance. Occasionally, hemangiomata may behave in a more aggressive manner, causing pathologic fracture or even symptoms/signs of nerve compression. In such cases, one must be careful not to assume that an atypical hemangioma is responsible. Coexisting, more malignant processes may be present and sometimes may be radiographically undetectable in the setting of acute fracture. This was the case in our patient.Study designCase report/university spine surgery center.MethodsThe patient underwent a corpectomy of her affected vertebra with conversion to a total spondylectomy when intraoperative frozen section was consistent with plasma cell neoplasm. A reconstruction with vertebral body replacement and fusion through anterior and posterior approaches was completed. Subsequently, the literature was reviewed for other cases of atypical hemangiomata to investigate the incidence of coexistent lesions.ResultsThis patient presented with pain secondary to an unstable pathologic vertebral body fracture. Surgery to stabilize her spine was elected. Intraoperative recognition of abnormal-appearing tissue led to the diagnosis of a plasma cell neoplasm that was not seen on imaging. Coexistent in the same vertebra was hemangiomatous tissue that was visible on preoperative imaging.ConclusionsThere are rare reports of aggressively behaving hemangiomata that mainly have occurred in the thoracic spine. There have been no reports of the coexistence of a hemangioma and a plasma cell tumor in the same vertebral level in the setting of acute compression fracture.  相似文献   
63.
64.
65.

Background

Arsenic exposure and micronutrient deficiencies may alter immune reactivity to influenza vaccination in pregnant women, transplacental transfer of maternal antibodies to the foetus, and maternal and infant acute morbidity.

Objectives

The Pregnancy, Arsenic, and Immune Response (PAIR) Study was designed to assess whether arsenic exposure and micronutrient deficiencies alter maternal and newborn immunity and acute morbidity following maternal seasonal influenza vaccination during pregnancy.

Population

The PAIR Study recruited pregnant women across a large rural study area in Gaibandha District, northern Bangladesh, 2018–2019.

Design

Prospective, longitudinal pregnancy and birth cohort.

Methods

We conducted home visits to enrol pregnant women in the late first or early second trimester (11–17 weeks of gestational age). Women received a quadrivalent seasonal inactivated influenza vaccine at enrolment. Follow-up included up to 13 visits between enrolment and 3 months postpartum. Arsenic was measured in drinking water and maternal urine. Micronutrient deficiencies were assessed using plasma biomarkers. Vaccine-specific antibody titres were measured in maternal and infant serum. Weekly telephone surveillance ascertained acute morbidity symptoms in women and infants.

Preliminary Results

We enrolled 784 pregnant women between October 2018 and March 2019. Of 784 women who enrolled, 736 (93.9%) delivered live births and 551 (70.3%) completed follow-up visits to 3 months postpartum. Arsenic was detected (≥0.02 μg/L) in 99.7% of water specimens collected from participants at enrolment. The medians (interquartile ranges) of water and urinary arsenic at enrolment were 5.1 (0.5, 25.1) μg/L and 33.1 (19.6, 56.5) μg/L, respectively. Water and urinary arsenic were strongly correlated (Spearman's ⍴ = 0.72) among women with water arsenic ≥ median but weakly correlated (⍴ = 0.17) among women with water arsenic < median.

Conclusions

The PAIR Study is well positioned to examine the effects of low-moderate arsenic exposure and micronutrient deficiencies on immune outcomes in women and infants. Registration : NCT03930017.  相似文献   
66.
67.
Eighteen brick kilns of three brick-making technologies (Fixed Chimney Kiln (FCK), Zigzag, and Hoffmann) were selected to measure the concentrations of particulate matter (PM2.5) with Aerocet 531S (USA) sampler, black carbon (BC) with Magee Scientific, OT-21 Soot scan Transmissometer (USA), and gaseous pollutants (CO2, CO, SO2, NOx, and volatile organic carbon (VOC)) with Aeroqual 500 gas sampler (New Zealand) to understand the emission scenario from brick sector in Greater Dhaka region, Bangladesh. Emission factor (EF) of each pollutant was computed from their respective concentration for three brick kiln technologies. Ambient PM2.5 and PM10 were measured in brick kiln premises and 1 km far from the respective kilns to see the effect on the surrounding areas. The PM2.5 concentration was found on an average of 141?±?86, 128?±?72, and 110?±?53 mg/m3 in FCK, Zigzag, and Hoffmann kilns, respectively. The average BC concentration was found 16.6?±?7.1 (FCK), 11.8?±?4.2 (Zigzag), and 8.9?±?4.4 (Hoffmann) mg/m3. FCK has a greater emission of CO, whereas Zigzag has a higher CO2 emission. A comparatively higher value of CO2 and lower value of CO indicates effective combustion of coal, and this is found to be more efficient for Zigzag and Hoffmann compared to traditional FCK. SO2 and VOC emissions were depending not only on the kiln types but also on the fuel qualities. From EF calculation, approximately 4526 t of PM2.5, 340 t of BC, 209,776 t of CO2, 8700 t of CO, 19,441 t of SO2, and 835,450 t of VOC per year found to emit from 1000 brick kilns. The conversion of traditional FCK to improved one, i.e., Zigzag and/or Hoffman is not a straight forward solution, as CO2 emission was higher in Zigzag whereas BC and PM2.5 emissions were higher in FCK. Therefore, considering EF of various pollutants from these three types of kilns, conversion of FCK to Zigzag or Hoffmann could be a better choice.  相似文献   
68.
Introduction: HIV-1-infected smokers are at risk of oxidative damage to neuronal cells in the central nervous system by both HIV-1 and cigarette smoke. Since neurons have a weak antioxidant defense system, they mostly depend on glial cells, particularly astrocytes, for protection against oxidative damage and neurotoxicity. Astrocytes augment the neuronal antioxidant system by supplying cysteine-containing products for glutathione synthesis, antioxidant enzymes such as SOD and catalase, glucose for antioxidant regeneration via the pentose-phosphate pathway, and by recycling of ascorbic acid.

Areas covered: The transport of antioxidants and energy substrates from astrocytes to neurons could possibly occur via extracellular nanovesicles called exosomes. This review highlights the neuroprotective potential of exosomes derived from astrocytes against smoking-induced oxidative stress, HIV-1 replication, and subsequent neurotoxicity observed in HIV-1-positive smokers.

Expert opinion: During stress conditions, the antioxidants released from astrocytes either via extracellular fluid or exosomes to neurons may not be sufficient to provide neuroprotection. Therefore, we put forward a novel strategy to combat oxidative stress in the central nervous system, using synthetically developed exosomes loaded with antioxidants such as glutathione and the anti-aging protein Klotho.  相似文献   

69.
Two ternary copper(II) complexes of dl-threonine and polypyridyl ligands with formula of [Cu(Thr)(Byp)Cl]·H2O (1) and [Cu(Thr)(Phen)H2O]Cl·2H2O (2) were synthesized. The complexes were characterized by spectral (NMR, FT-IR, and UV–Vis), CHN elemental analysis and have been structurally elucidated by X-ray crystallography. Both of the complexes formed slightly distorted square-pyramidal coordination geometry. The electronic absorption spectra of the complexes showed a very low intensity dd electronic band in the range of 610–620 nm in Tris–HCl/NaCl (5:5 mM) pH 7.2 buffer solution. The DNA binding interaction with calf-thymus DNA (CT-DNA) was investigated by electronic absorption spectral titration and viscosity measurements. The results revealed that the phenanthroline complex (2) interact with CT-DNA through intercalation while bipyridyl complex (1) through the groove binding mode. The calculated intrinsic binding constant (K b) of (1) and (2) were 0.5 and 4.4 × 105 M?1, respectively. Both the complexes were found to promote efficient DNA cleavage activities at low concentration in the presence of H2O2. The results showed that (2) has the highest DNA binding and nuclease activity. Furthermore, both the complexes were tested against human colon cancer (HCT 116) and breast cancer (MCF-7) cell lines and showed a dose-dependent antiproliferation effect.  相似文献   
70.

Background context

Posterior cervical foraminotomy (PCF) with or without microdiscectomy (posterior cervical discectomy [PCD]) is a frequently used surgical technique for cervical radiculopathy secondary to foraminal stenosis or a laterally located herniated disc. Currently, these procedures are being performed with increasing frequency using advanced minimally invasive techniques. Although the safety and efficacy of minimally invasive PCF/PCD (MI-PCF/PCD) have been established, reports on long-term outcome and need for secondary surgical intervention at the index or adjacent level are lacking.

Purpose

To determine the rates of complications, long-term outcomes, and need for secondary surgical intervention at the index or adjacent level after MI-PCF and microdiscectomy.

Study design

Retrospective analysis of a prospective cohort.

Patient sample

Seventy patients treated with MI-PCF and/or MI-PCD for cervical radiculopathy.

Outcome measures

Visual Analog Scale for neck/arm (VASN/A) pain and Neck Disability Index (NDI).

Methods

Ninety-seven patients underwent MI-PCF with or without MI-PCD between 2002 and 2011. Adequate prospective follow-up was available for 70 patients (95 cervical levels). The primary outcome assessed was need for secondary surgical intervention at the index or adjacent level. The secondary outcomes assessed included complications and improvements in NDI and VASN/A scores. All complications were reviewed. Mixed-model analyses of variance with random subject effects and autoregressive first-order correlation structures were used to test for differences among NDI, VASA, and VASN measurements made over time while accounting for the correlation among repeated observations within a patient. All statistical hypothesis tests were conducted at the 5% level of significance.

Results

Patients were followed for a mean of 32.1 months. Of 70 patients operated, there were 3 (4.3%) complications (1 cerebrospinal fluid leak, 1 postoperative wound hematoma, and 1 radiculitis), none of which required a secondary operative intervention. Five patients required an anterior cervical discectomy and fusion (eight total levels fused) on average 44.4 months after the index surgery. Of those, five (5.3%) were at the index level and three (2.1%) were at adjacent levels. Neck Disability Index scores improved significantly (p<.0001) immediately postoperatively and continued to decrease gradually with time. Visual Analog Scale for neck/arm scores improved significantly (p<.0001) from baseline immediately postoperatively but tended to plateau with time.

Conclusions

Minimally invasive PCF with or without MI-PCD is an excellent alternative for cervical radiculopathy secondary to foraminal stenosis or a laterally located herniated disc. There is a low rate (1.1% per index level per year) of future index site fusion and a very low rate (0.9% per adjacent level per year) of adjacent-level disease requiring surgery.  相似文献   
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