Prototype of Low-Cost Microvascular Clips for Laboratory Use.

BACKGROUND: Vascular neurosurgical procedures require temporary or permanent surgical clips to treat cerebral aneurysms, arteriovenous malformations, or bypass surgery. In this scenario, surgical clips should have specific characteristics such as high-quality material, proper design, closing force, and biocompatibility. Due to these characteristics, the price of these clips does not allow their availability at the experimental surgery laboratory worldwide. METHODS: We describe here the technique for manufacturing handcrafted clips of low cost, using dental stainless steel or titanium wire of 0.18 mm, 0.20 mm, or 0.22 mm in diameter. We must complete six steps to obtain the clip using our hands and small electrician needle nose pliers for wire molding. RESULTS: These clips have a closing force of 30-60 gr/cm2 (depending on the wire diameter). They can be used in the experimental surgery laboratory to clip arteries or veins during vascular microsurgery procedures. Also, they can be used as temporary clips with confidence in low-flow bypass (v.gr. superficial temporal artery to middle cerebral artery or occipital artery to posterior inferior cerebellar artery anastomoses). CONCLUSIONS: Making practical low-cost clips for use in laboratory procedures or during low-flow anastomosis as temporary clips is possible. The main advantages are the low cost and the worldwide availability of the basic materials. The main disadvantage is the learning curve to get the ability to master the manufacturing of these clips.

The impact of the COVID-19 pandemic on people living with HIV: a cross-sectional study in Caracas, Venezuela.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has disrupted multiple health services, including human immunodeficiency virus (HIV) testing, care, and treatment services, jeopardizing the achievement of the Joint United Nations Programme on HIV/AIDS 90-90-90 global target. While there are limited studies assessing the impact of the COVID-19 pandemic on people living with HIV (PLHIV) in Latin America, there are none, to our knowledge, in Venezuela. This study aims to assess the impact of the COVID-19 pandemic among PLHIV seen at the outpatient clinic of a reference hospital in Venezuela. METHODS: We conducted a cross-sectional study among PLHIV aged 18 years and over seen at the Infectious Diseases Department of the University Hospital of Caracas, Venezuela between March 2021 and February 2022. RESULTS: A total of 238 PLHIV were included in the study. The median age was 43 (IQR 31-55) years, and the majority were male (68.9%). Most patients (88.2%, n = 210) came for routine check-ups, while 28 (11.3%) were newly diagnosed. The majority of patients (96.1%) were on antiretroviral therapy (ART), but only 67.8% had a viral load test, with almost all (95.6%) being undetectable. Among those who attended regular appointments, 11.9% reported missing at least one medical consultation, and 3.3% reported an interruption in their ART refill. More than half of the patients (55.5%) had received at least one dose of the COVID-19 vaccine, while the rest expressed hesitancy to get vaccinated. Most patients with COVID-19 vaccine hesitancy were male (65.1%), younger than 44 years (57.5%), employed (47.2%), and had been diagnosed with HIV for less than one year (33%). However, no statistically significant differences were found between vaccinated patients and those with COVID-19 vaccine hesitancy. Older age was a risk factor for missing consultations, while not having an alcoholic habit was identified as a protective factor against missing consultations. CONCLUSION: This study found that the COVID-19 pandemic had a limited impact on adherence to medical consultations and interruptions in ART among PLHIV seen at the University Hospital of Caracas, Venezuela.

New daily persistent headache after SARS-CoV-2 infection in Latin America: a cross-sectional study.

BACKGROUND: Persistent headache is a frequent symptom after coronavirus disease 2019 (COVID-19) and there is currently limited knowledge about its clinical spectrum and predisposing factors. A subset of patients may be experiencing new daily persistent headache (NDPH) after COVID-19, which is among the most treatment-refractory primary headache syndromes. METHODS: We conducted a cross-sectional study in Latin America to characterize individuals with persistent headache after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to identify factors associated with NDPH. Participants over 18 years old who tested positive for SARS-CoV-2 infection and reported persistent headache among their symptoms completed an online survey that included demographics, past medical history, persistent headache clinical characteristics, and COVID-19 vaccination status. Based on participants' responses, NDPH diagnostic criteria were used to group participants into NDPH and non-NDPH groups. Participant data was summarized by descriptive statistics. Student's t and Mann-Whitney U tests were used according to the distribution of quantitative variables. For categorical variables, Pearson's chi-square and Fisher's exact tests were used according to the size of expected frequencies. Binomial logistic regression using the backward stepwise selection method was performed to identify factors associated with NDPH. RESULTS: Four hundred and twenty-one participants from 11 Latin American countries met the inclusion criteria. One in four participants met the NDPH diagnostic criteria. The mean age was 40 years, with most participants being female (82%). Over 90% of the participants reported having had mild/moderate COVID-19. Most participants had a history of headache before developing COVID-19 (58%), mainly migraine type (32%). The most predominant clinical characteristics in the NDPH group were occipital location, severe/unbearable intensity, burning character, and radiating pain (p < 0.05). A higher proportion of anxiety symptoms, sleep problems, myalgia, mental fog, paresthesia, nausea, sweating of the face or forehead, and ageusia or hypogeusia as concomitant symptoms were reported in participants with NDPH (p < 0.05). Palpebral edema as a concomitant symptom during the acute phase of COVID-19, occipital location, and burning character of the headache were risk factors associated with NDPH. CONCLUSION: This is the first study in Latin America that explored the clinical spectrum of NDPH after SARS-CoV-2 infection and its associated factors. Clinical evaluation of COVID-19 patients presenting with persistent headache should take into consideration NDPH.

Benign and Malignant Breast Tumor Classification in Ultrasound and Mammography Images via Fusion of Deep Learning and Handcraft Features.

Breast cancer is a disease that affects women in different countries around the world. The real cause of breast cancer is particularly challenging to determine, and early detection of the disease is necessary for reducing the death rate, due to the high risks associated with breast cancer. Treatment in the early period can increase the life expectancy and quality of life for women. CAD (Computer Aided Diagnostic) systems can perform the diagnosis of the benign and malignant lesions of breast cancer using technologies and tools based on image processing, helping specialist doctors to obtain a more precise point of view with fewer processes when making their diagnosis by giving a second opinion. This study presents a novel CAD system for automated breast cancer diagnosis. The proposed method consists of different stages. In the preprocessing stage, an image is segmented, and a mask of a lesion is obtained; during the next stage, the extraction of the deep learning features is performed by a CNN-specifically, DenseNet 201. Additionally, handcrafted features (Histogram of Oriented Gradients (HOG)-based, ULBP-based, perimeter area, area, eccentricity, and circularity) are obtained from an image. The designed hybrid system uses CNN architecture for extracting deep learning features, along with traditional methods which perform several handcraft features, following the medical properties of the disease with the purpose of later fusion via proposed statistical criteria. During the fusion stage, where deep learning and handcrafted features are analyzed, the genetic algorithms as well as mutual information selection algorithm, followed by several classifiers (XGBoost, AdaBoost, Multilayer perceptron (MLP)) based on stochastic measures, are applied to choose the most sensible information group among the features. In the experimental validation of two modalities of the CAD design, which performed two types of medical studies-mammography (MG) and ultrasound (US)-the databases mini-DDSM (Digital Database for Screening Mammography) and BUSI (Breast Ultrasound Images Dataset) were used. Novel CAD systems were evaluated and compared with recent state-of-the-art systems, demonstrating better performance in commonly used criteria, obtaining ACC of 97.6%, PRE of 98%, Recall of 98%, F1-Score of 98%, and IBA of 95% for the abovementioned datasets.

Plasmodium vivax and SARS-CoV-2 co-infection in Venezuelan pregnant women: a case series.

BACKGROUND: Malaria-endemic areas are not spared from the impact of coronavirus disease 2019 (COVID-19), leading to co-infection scenarios where overlapping symptoms impose serious diagnostic challenges. Current knowledge on Plasmodium spp. and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) co-infection in pregnant women remains limited, especially in Latin America, where Plasmodium vivax infection is highly prevalent. METHODS: This is a case series of five pregnant women with P. vivax and SARS-CoV-2 co-infection hospitalized in two main malaria referral centers of the Capital District and Bolivar state, Venezuela between March 13, 2020 and December 31, 2021. RESULTS: Clinical and laboratory data from five pregnant women with a mean age of 22 years were analyzed; three of them were in the third trimester of pregnancy. Comorbidities included obesity in two cases, hypertension in one, and asthma in one. Three out of five patients had severe to critical COVID-19 disease. Dry cough, fever, chills, and headache were the most frequent symptoms reported. Laboratory analyses showed elevated aspartate/alanine aminotransferase and creatinine levels, thrombocytopenia, and severe anemia as the most relevant abnormalities. The mean period between symptom onset and a positive molecular test for SARS-CoV-2 infection or positive microscopy for Plasmodium spp. was 4.8 ± 2.5 days and 2.8 ± 1.6 days, respectively. The mean hospital stay was 5.4 ± 7 days. Three women recovered and were discharged from the hospital. Two women died, one from cerebral malaria and one from respiratory failure. Three adverse fetal outcomes were registered, two miscarriages and one stillbirth. CONCLUSION: This study documented a predominance of severe/critical COVID-19 disease and a high proportion of adverse maternal-fetal outcomes among pregnant women with malaria and COVID-19 co-infection. More comprehensive prospective cohort studies are warranted to explore the risk factors, management challenges, and clinical outcomes of pregnant women with this co-infection.

Clinical-epidemiological characteristics and maternal-foetal outcomes in pregnant women hospitalised with COVID-19 in Venezuela: a retrospective study.

BACKGROUND: In low- and middle-income countries, pregnant women and newborns are more vulnerable to adverse outcomes from coronavirus disease 2019 (COVID-19). However, in Venezuela, there are no integrated data in a national surveillance system to identify the clinical-epidemiological characteristics and maternal-foetal outcomes of pregnant women hospitalised with COVID-19. METHODS: A retrospective study was conducted among Venezuelan pregnant women hospitalised with COVID-19 seen at the "Ruiz y Páez" University Hospital Complex and the San Cristobal Central Hospital between June 2020 and September 2021. Information was obtained from physical and digitised clinical records using a purpose-designed proforma to collect epidemiological, clinical, paraclinical, treatment, obstetric and perinatal complications, and maternal-foetal outcomes data. RESULTS: A total of 80 pregnant women with confirmed severe acute respiratory syndrome coronavirus 2 infection were seen within the study period, 59 (73.8%) survived and 21 (26.2%) died. The median (interquartile range) age was 29 (23-33) years, the majority being in the third trimester of pregnancy (81.2%; n = 65). Interestingly, four (5%) pregnant women were co-infected with malaria by Plasmodium vivax and three (3.8%) with syphilis. The most frequent symptoms were fever (75%; n = 60), dry cough (68.8%; n = 55), dyspnoea (55%; n = 44), and headache (53.8%; n = 43). The most frequent maternal complications were anaemia (51.5%; n = 66) and hypertensive disorders of pregnancy (17.5%; n = 14). The most frequent perinatal complications were preterm delivery (39.2%; n = 20/51) and oligohydramnios (31.3%; n = 25). A total of 29 (36.3%) adverse foetal outcomes were documented, 21 stillbirth and eight abortions. CONCLUSION: This is the first study to describe the clinical-epidemiological behaviour of COVID-19 in hospitalised Venezuelan pregnant women. Anaemia, hypertensive disorders of pregnancy, oligohydramnios, and low birth weight were the most frequent maternal-foetal complications in this population of pregnant women.

Microsurgical treatment of carotid body tumors using periadventitial dissection: Analysis of outcomes and prognostic factors in a neurological referral center.

Background: Surgical resection for carotid body tumors (CBTs) is the gold standard of treatment and continues to be a challenging procedure, commonly associated with high vascular injury rates and neurological complications. Methods: It is a retrospective case series study between January 2002 and November 2020, with a mean follow-up of 29 months in a single nationwide referral center. Thirty-one patients diagnosed with a carotid body tumor and treated with microsurgical periadventitial resection were included in the study. Patients' demographics, comorbidities, clinical, radiological factors, and tumor grade, evaluated by the Shamblin scale, were obtained. Statistical analysis was performed on all collected data. Results: In this study, we included 31 patients (32 tumors), 80% of the patients were female, and 20% were male, with a mean age of 53 years. One patient presented with bilateral lesions, while 17 tumors were located on the left side. The most frequent symptom was a painless, slow-growing neck mass in 74% of patients. Using the Shamblin classification, 13% of tumors were Grade I, 53% Grade II, and 34% Grade III. In the postoperative period, 3% of patients presented with permanent cranial nerve deficit, while none had vascular injuries or postoperative stroke. A tumor >5 cm increased the risk for nerve lesion by 11 times (OR 12.6, CI 95% 7.4-11.4, P < 0.001). Conclusion: Preoperative embolization followed by periadventitial resection by means of a microsurgical technique is a safe and effective approach to remove CBT, with 3% cranial nerve injury rate and no need for vascular sacrifice or reconstruction.

Treatment of middle cerebral artery aneurysms: A comparative study and proposed treatment algorithm.

OBJECTIVES: We aimed to compare outcomes of patients with middle cerebral artery (MCA) aneurysms treated by either microsurgical clipping or endovascular therapy and provide a treatment algorithm based on available evidence. MATERIALS AND METHODS: We performed a retrospective analysis of 77 patients with 95 MCA aneurysms. Demographic, clinical, and aneurysm morphological variables were collected. Patients were divided into two groups depending on the received treatment. Clinical and radiological outcomes were collected at the end of a 1-year follow-up period and compared between both treatment groups. RESULTS: Mean age was 51.4 years. Fifty patients (65%) underwent microsurgical clipping and 27 (35%) were treated by endovascular therapy. Fifty-four patients (70%) presented with subarachnoid hemorrhage, while 23 (30%) were treated for unruptured aneurysms. Patients with subarachnoid hemorrhage were more frequently treated by microsurgical clipping than patients with unruptured aneurysms. Clinical outcomes, including functional status, were similar between treatment groups after 1-year follow-up even when adjusting for clinical presentation. Residual aneurysms were found less frequently in the microsurgical group (OR = 0.09; p < 0.001). CONCLUSIONS: In patients with MCA aneurysms, clinical outcomes at 1 year are similar between microsurgical clipping and endovascular therapy. However, microsurgery is associated with a lower risk of residual aneurysms.

OBJETIVO: Evaluar y comparar desenlaces de pacientes con aneurismas de arteria cerebral media (ACM) tratados mediante clipaje microquirúrgico o terapia endovascular, y proponer un algoritmo de tratamiento basado en evidencia. MATERIAL Y MÉTODOS: Estudio retrospectivo de 77 pacientes con 95 aneurismas de ACM. Se recabaron variables demográficas, clínicas y morfológicas de los aneurismas tratados. Se dividieron a los pacientes en dos grupos dependiendo del tratamiento recibido y se compararon los desenlaces clínicos y radiológicos al final del seguimiento a un año entre ambos grupos. RESULTADOS: La edad promedio fue 51.4 años. 50 pacientes (65%) fueron sometidos a clipaje microquirúrgico y 27 (35%) a terapia endovascular. 54 pacientes (70%) presentaron hemorragia subaracnoidea, quienes fueron tratados mediante microcirugía en mayor proporción que aquellos con aneurismas no rotos. Los desenlaces clínicos, incluyendo el estado funcional, fueron similares entre ambos grupos al año de seguimiento, aún tras ajustar el análisis por presentación clínica. El grupo de microcirugía presentó una menor proporción de aneurismas residuales (OR = 0.09; p < 0.001). CONCLUSIONES: En pacientes con aneurismas de ACM, los desenlaces clínicos a un año son similares entre clipaje microquirúrgico y terapia endovascular. Sin embargo, la microcirugía se asocia a un menor riesgo de aneurismas residuales.

Operative considerations and surgical treatment of sylvian fissure arteriovenous malformations: a 20-year experience.

OBJECTIVE: Sylvian fissure (SF) arteriovenous malformations (AVMs) are among the most challenging vascular lesions amenable to neurosurgical treatment and account for 10% of all locations. As radiosurgery and endovascular techniques are increasingly involved in multimodal management protocols, the role of microsurgery needs to be reassessed as a stand-alone technique. The aim of this study was to show that total excision can be achieved with reasonable levels of morbidity and mortality in a real-world setting from a specialized high-volume center. METHODS: Forty-three patients with SF AVMs were identified from a series of 577 AVM patients treated microsurgically over a 22-year period. The mean patient age was 33.07 years (range 15-60 years), and there were 22 male and 21 female patients. The mode of presentation was headache in 51.2%, hemorrhage in 34.9%, seizures in 30.2%, and steal phenomenon in 9.3%. The authors analyzed the anatomical basis and angiographic characteristics of such lesions. RESULTS: In the preoperative period, 83.7% of the patients had a modified Rankin Scale (mRS) score of 0-2, and 16.3% had an mRS score of 3-5. After a 12-month follow-up, 95.3% of patients had an mRS score of 0-2, and 4.7% had a score of 3-6. The difference between pre- and postoperative scores was not statistically significant. SF AVMs have several particular features: 1) They produce angiographic steal of the anterior cerebral artery. 2) The nidus is fed by only one of the main trunks of the middle cerebral artery (MCA). 3) Participation of deep perforators is uncommon. 4) They have two or more early draining veins showing their fistulous nature. 5) Preoperative embolization and radiosurgery have a low rate of permanent cure. CONCLUSIONS: These AVMs represent a surgical challenge due to their proximity to critical structures such as the MCA, insula, internal capsule, and speech and memory functions in the dominant hemisphere. Essential key points are the wide opening of the SF and proper differentiation between feeders and normal vessels. Although this location can seem daunting, SF AVMs carry no additional surgical risk if adequately managed.

First wave of COVID-19 in Venezuela: Epidemiological, clinical, and paraclinical characteristics of first cases.

The coronavirus disease 2019 (COVID-19) pandemic has particularly affected countries with weakened health services in Latin America, where proper patient management could be a critical step to address the epidemic. In this study, we aimed to characterize and identify which epidemiological, clinical, and paraclinical risk factors defined COVID-19 infection from the first confirmed cases through the first epidemic wave in Venezuela. A retrospective analysis of consecutive suspected cases of COVID-19 admitted to a sentinel hospital was carried out, including 576 patient cases subsequently confirmed for severe acute respiratory syndrome coronavirus 2 infection. Of these, 162 (28.1%) patients met the definition criteria for severe/critical disease, and 414 (71.2%) were classified as mild/moderate disease. The mean age was 47 (SD 16) years, the majority of which were men (59.5%), and the most frequent comorbidity was arterial hypertension (23.3%). The most common symptoms included fever (88.7%), headache (65.6%), and dry cough (63.9%). Severe/critical disease affected mostly older males with low schooling (p < 0.001). Similarly, higher levels of glycemia, urea, aminotransferases, total bilirubin, lactate dehydrogenase, and erythrocyte sedimentation rate were observed in severe/critical disease patients compared to those with mild/moderate disease. Overall mortality was 7.6% (44/576), with 41.7% (28/68) dying in hospital. We identified risk factors related to COVID-19 infection, which could help healthcare providers take appropriate measures and prevent severe clinical outcomes. Our results suggest that the mortality registered by this disease in Venezuela during the first epidemic wave was underestimated. An increase in fatalities is expected to occur in the coming months unless measures that are more effective are implemented to mitigate the epidemic while the vaccination process is ongoing.

Amoebic liver abscess in a COVID-19 patient: a case report.

BACKGROUND: Amoebiasis is a parasitic disease caused by Entamoeba histolytica, which affects people living in low- and middle-income countries and has intestinal and extraintestinal manifestations. To date, knowledge on coronavirus disease 2019 (COVID-19) coinfection with enteric parasites is limited, and E. histolytica coinfection has not been previously described. Here we present the case of a patient with COVID-19 who, during hospitalisation, presented a clinical picture consistent with an amoebic liver abscess (ALA). CASE PRESENTATION: A 54-year-old man, admitted as a suspected case of COVID-19, presented to our hospital with dyspnoea, malaise, fever and hypoxaemia. A nasopharyngeal swab was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse-transcription polymerase chain reaction. After 7 days, he developed diarrhoea, choluria and dysentery. An abdominal ultrasound showed a lesion compatible with a liver abscess; stool examination revealed E. histolytica trophozoites, and additional serology for E. histolytica was positive. After 12 days of treatment with metronidazole, ceftazidime and nitazoxanide, the patient reported acute abdominal pain, and an ultrasound examination revealed free liquid in the abdominal cavity. An emergency exploratory laparotomy was performed, finding 3000 mL of a thick fluid described as "anchovy paste". Computed tomography scan revealed a second abscess. He ended up receiving 21 days of antibiotic treatment and was discharged with satisfactory improvement. CONCLUSION: Here we present, to the best of our knowledge, the first report of ALA and COVID-19 co-presenting. Based on their pathophysiological similarities, coinfection with SARS-CoV-2 and E. histolytica could change the patient's clinical course; however, larger studies are needed to fully understand the interaction between these pathogens.

Knowledge, Attitudes, and Practices Regarding COVID-19 Among Healthcare Workers in Venezuela: An Online Cross-Sectional Survey.

Background: The deterioration of Venezuela's health system in recent years undoubtedly contributes to an increased impact of the COVID-19 pandemic. Understanding healthcare workers' (HCWs) knowledge, attitudes, and practices (KAPs) toward COVID-19 in the early stages of the pandemic could inform their medical training and improve their preparedness. Methods: A online national cross-sectional survey was conducted between May 26th and May 30th, 2020, to assess KAPs among HCWs in Venezuela. Results: A total of 1,441 HCWs from all 24 regions of the country responded to the survey. The mean age of the HCWs was 44 (SD [standard deviation] 14) years; most were women (66.4%). Most HCWs were specialized doctors (48%), followed by nurses (13%) and resident doctors (12.3%). The majority of HCWs had good knowledge (76.3%), obtained information mainly from scientific literature (85.4%); had negative attitudes (53.6%), felt uncomfortable with their work during the current pandemic (59.8%); and reported appropriate practices (76.9%). However, participation in COVID-19 related training was absent in more than half of the HCWs. Positive attitudes were significantly more frequent in frontline workers than in non-frontline workers (p = 0.001). Bioanalysts, students, and doctors were more likely to have good knowledge; participating in training was a predictor for positive attitudes and older age was an appropriate practice predictor. Conclusions: HCWs, knowledge in Venezuela could be improved by strengthening education and training programs. Strategies should focus on reducing fear and improving attitudes toward the care of COVID-19 patients, as well as the promotion of preventive practices.

Valorization of agro-industrial wastes by producing 2-phenylethanol via solid-state fermentation: Influence of substrate selection on the process.

2-phenylethanol (2-PE) is a value-added compound widely used in industry due to its rose-like odor and antibacterial properties that can be bioproduced using wastes as raw materials. This study presents the valorization of nine agro-industrial wastes as potential substrates for 2-PE production using an isolated 2-PE producer Pichia kudriavzevii, and the solid-state fermentation (SSF) technology as an alternative approach. The assessed substrates comprised wastes of varied traits such that each of them provided different characteristics to the fermentation. Thus, by using a principal component analysis (PCA), it was possible to identify the most significant characteristics associated with the substrates affecting the 2-PE production. Results show that L-phenylalanine biotransformation was more efficient than de novo synthesis for producing 2-PE. Besides, from the evaluated set, the maximum 2-PE production was achieved with red apple pomace, reaching 1.7 and 25.2 mg2PE per gram of used waste through de novo and L-phenylalanine biotransformation, respectively. In that scenario, volumetric productivity and precursor yield were 39.6 mg2PE L-1h-1 and 0.69 g2PE per gram of L-phenylalanine added, respectively. From the PCA, it was identified that the reducing sugars content of the substrate, the air-filled porosity of the bed and the L-phenylalanine availability were the most critical parameters (associated with the substrates) influencing the microbial activity and 2-PE production. These results suggest that the desirable traits a solid media needs for promoting 2-PE production via SSF could be reached by using a combination of wastes in a synergistic approach.

Brewer's spent grain as a no-cost substrate for polyhydroxyalkanoates production: Assessment of pretreatment strategies and different bacterial strains.

Polyhydroxyalkanoates (PHAs) are polyesters of significant interest due to their biodegradability and properties similar to petroleum-derived plastics, as well as the fact that they can be produced from renewable sources such as by-product streams. In this study, brewer's spent grain (BSG), the main by-product of the brewing industry, was subjected to a set of physicochemical pretreatments and their effect on the release of reducing sugars (RS) was evaluated. The RS obtained were used as a substrate for further PHA production in Burkholderia cepacia, Bacillus cereus, and Cupriavidus necator in liquid cultures. Although some pretreatments proved efficient in releasing RS (acid-thermal pretreatment up to 42.1 gRS L-1 and 0.77 gRS g-1 dried BSG), the generation of inhibitors in such scenarios likely affected PHA production compared with the process run without pretreatment (direct enzymatic hydrolysis of BSG). Thus, the maximum PHA accumulation from BSG hydrolysates was found in the reference case with 0.31 ±â€¯0.02 g PHA per g cell dried weight, corresponding to 1.13 ±â€¯0.06 g L-1 and a PHA yield of 23 ±â€¯1 mg g-1 BSG. It was also found that C. necator presented the highest PHA accumulation of the tested strains followed closely by B. cepacia, reaching their maxima at 48 h. Although BSG has been used as a source for other bioproducts, these results show the potential of this by-product as a no-cost raw material for producing PHAs in a waste valorization and circular economy scheme.

Dissection of the Superficial Temporal Artery: Significance and Performance with Bipolar Forceps.

BACKGROUND: Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory. METHODS: Here, we report the effectiveness of using the bipolar forceps as a novel procedure. RESULTS: This procedure improves safety, efficiency, and bleeding compared to the usual dissection. CONCLUSIONS: In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.

Preliminary experience in the management of brain and skull-base tumors with microwave ablation; feasibility guided by ultrasound, report from 23 cases.

BACKGROUND: In surgery involving brain tumors, the use of new tools or equipment that allows for better results and improvement in the quality of life of the patients is mandatory. Microwave ablation (MWA) is a technique that has been used effectively since 1994 in the management of different kinds of tumors. The authors present their surgical experience with 23 cases of brain and skull-base tumors using MWA technique. METHODS: In all, 23 cases diagnosed with brain and skull-base tumors are described; all of these were treated with MWA as unique technique as a complement to conventional microsurgical tumor resection. In all cases, ultrasound imaging guidance was used. A thin antenna (caliber 14.5; MedWaves) was positioned through ultrasound images to a central intratumoral area, and then energy was applied for 1-3 min until the temperature sensor in the proximal position of the antenna reached 80-100°C. Through transoperative Doppler ultrasound images and surgical microscopy, changes in the generated ablation were observed. The said ablation led to a decrease in intratumoral blood flow, and the adjacent vascular and cerebral structures were preserved. RESULTS: The application of MWA during brain surgery was regarded as safe in all cases, as no permanent additional neurological deficit was detected. Intratumoral vascular flow was also reduced and tumor resection was facilitated. Likewise, a reduction in tumor volume was noted, and in others in whom the ablation was applied as a single therapy, a progressive destruction of the tumor was observed. CONCLUSION: MWA can be a useful tool as a single therapy or as a complement to conventional techniques for the surgical resection of brain and skull-base tumors. It was a safe method in all cases, producing a decrease in intratumoral blood flow, and this procedure facilitates the microsurgical resection of the lesion.

Fed-Batch and Sequential-Batch Approaches To Enhance the Bioproduction of 2-Phenylethanol and 2-Phenethyl Acetate in Solid-State Fermentation Residue-Based Systems.

This study describes the use of alternative operational strategies in the solid-state fermentation of the agro-industrial leftover sugar cane bagasse (SCB) supplemented with l-phenylalanine, for bioproducing natural 2-phenylethanol (2-PE) and 2-phenethyl acetate (2-PEA) using K. marxianus. Here, fed-batch and sequential-batch have been assessed at two scales (1.6 and 22 L) as tools to increase the production, as well as to enhance the sustainability of this residue-based process. While in the reference batch strategy a maximum of 17 mg of 2-PE+2-PEA per gram of added SCB was reached at both scales, the implementation of fed-batch mode induced a production increase of 11.6% and 12.5%, respectively. Also, the production was increased by 16.9% and 2.4% as compared to the batch when a sequential-batch mode was used. Furthermore, the use of these strategies was accompanied by lower consumption of key resources like the inoculum, air, and time, promoting savings between 22% and 76% at both scales.