44 research outputs found
Morfología del sistema reproductor y del espermatóforo de Litopenaeus vannamei, camarón blanco del Pacífico
In order to advance in the knowledge of the male reproductive system of Litopanaeus vannamei, the anatomical description of its reproductive system in sexually mature animals was performed. Animals were obtained from a Mexican shrimp hatchery, located in Sinaloa, Mexico. To describe the anatomy, a) 8 male reproductive systems were removed; b) 10 spermatophores compounds were extracted from naturally inseminated females; and c) 40 sperm sacs derived from the right and the left ampulla were manually extracted. In general, the reproductive system was found similar to the observed in other species of the genus Penaeus. However, differences in the shape of the testes and of the terminal ampulla that are characteristic of this species were observed. An area located between the anterior vas deferens and the middle duct, known in other species as blind pouch, was observed. The compound spermatophore is a structure that has been described anatomically, although when freshly extracted it is difficult to observe because the type of substances that compose it and because of the morphological changes introduced when it contacts water. In each sperm sac of the spermatophore, sperm chamber is located from its medial to its distal part, with the highest concentration of sperm in the distal region.Con el objetivo de aportar información al conocimiento del sistema reproductor en machos de Litopenaeus vannamei, se elaboró la descripción anatómica de su sistema reproductor, empleando para ello machos sexualmente maduros, obtenidos de un laboratorio productor de larvas ubicado en Sinaloa, México. Para hacer la descripción, se obtuvieron por disección: a) los órganos reproductores completos de 8 machos; b) 10 espermatóforos compuestos que fueron extraídos de hembras inseminadas naturalmente; y c) 40 sacos espermáticos extraídos manualmente de las ámpulas derecha e izquierda. El sistema reproductor se asemeja al de otras especies del género Penaeus, sin embargo, posee diferencias en la forma de los testículos y del ámpula terminal, que lo hace característico de esta especie. También se localizó un área diferenciada entre el conducto deferente anterior y el conducto deferente medio que ha sido denominada en otras especies como saco ciego. El espermatóforo compuesto es una estructura que ha sido descrita anatómicamente, aunque su observación en fresco es difícil de realizar por el tipo de sustancias que lo forman y los cambios morfológicos que presenta al tener contacto con el agua. En cada uno de las sacos espermáticos del espermatóforo, la cámara espermática abarca desde la parte media hasta la parte distal del mismo, encontrándose la mayor concentración de espermatozoides en la región distal
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Why the Mexican Oyster Fishery in the Gulf of Mexico Is Underdeveloped?
The Mexican Oyster fishery in the Gulf of Mexico annually produces only
50,000 MT, 95% of Mexico oyster production. Oyster production has
fallen drastically in most coastal lagoons, this decline has been attributed to
factors as overfishing, mismanagement of natural oyster beds,
environmental degradation and lagoons pollution. This work proposes
strategies for oyster fishery management on Gulf of Mexico littoral. In
order to achieve this goal oyster fishery diagnose for Tamaulipas,
Veracruz, Tabasco and Campeche states were made for evaluation of
ecological, economics, legal and social aspects trough information sources
as statistical yearbooks, databases, and published information relative to
regional oyster fishery, simultaneously visits to landing places where made
and inquiries to production units, directives, fishermen and decision makers
were done. Collected information was grouped and analyzed with SWOT
analysis. Oyster fishery is carried on in 20 coastal ecosystems where works
51 production units with 2,955 active oyster fishermen. In every visited site
were observed water pollution, coastal deforestation and or overfishing.
National and international oysters markets cannot grow for several reasons
including sanitary quality; there are no efficient models for oyster beds
administration, no infrastructure for give oyster products additional value.
Some of the strategies for solve these difficulties are, to make local
diagnosis and promote social organization for control of water quality,
market research for oyster products and laboratory seed production, register
efficiently and responsibly catch statistics, to make official norms on size
catch, fishing gear, fishing, reception, packing, commercialization, culture
techniques, and cultured oyster sizes, these strategies and other programs
may permit sustainable and biotechnological development in oyster fishery.Keywords: Fisheries Economics, Fish and Aquaculture Sectors Development, Fisheries Dynamic
Effect of viral storm in patients admitted to intensive care units with severe COVID-19 in Spain: a multicentre, prospective, cohort study
Background: The contribution of the virus to the pathogenesis of severe COVID-19 is still unclear. We aimed to evaluate associations between viral RNA load in plasma and host response, complications, and deaths in critically ill patients with COVID-19. Methods: We did a prospective cohort study across 23 hospitals in Spain. We included patients aged 18 years or older with laboratory-confirmed SARS-CoV-2 infection who were admitted to an intensive care unit between March 16, 2020, and Feb 27, 2021. RNA of the SARS-CoV-2 nucleocapsid region 1 (N1) was quantified in plasma samples collected from patients in the first 48 h following admission, using digital PCR. Patients were grouped on the basis of N1 quantity: VIR-N1-Zero ([removed]2747 N1 copies per mL). The primary outcome was all-cause death within 90 days after admission. We evaluated odds ratios (ORs) for the primary outcome between groups using a logistic regression analysis. Findings: 1068 patients met the inclusion criteria, of whom 117 had insufficient plasma samples and 115 had key information missing. 836 patients were included in the analysis, of whom 403 (48%) were in the VIR-N1-Low group, 283 (34%) were in the VIR-N1-Storm group, and 150 (18%) were in the VIR-N1-Zero group. Overall, patients in the VIR-N1-Storm group had the most severe disease: 266 (94%) of 283 patients received invasive mechanical ventilation (IMV), 116 (41%) developed acute kidney injury, 180 (65%) had secondary infections, and 148 (52%) died within 90 days. Patients in the VIR-N1-Zero group had the least severe disease: 81 (54%) of 150 received IMV, 34 (23%) developed acute kidney injury, 47 (32%) had secondary infections, and 26 (17%) died within 90 days (OR for death 0·30, 95% CI 0·16–0·55; p<0·0001, compared with the VIR-N1-Storm group). 106 (26%) of 403 patients in the VIR-N1-Low group died within 90 days (OR for death 0·39, 95% CI 0·26–0·57; p[removed]11 página
White spot syndrome virus: an overview on an emergent concern
Viruses are ubiquitous and extremely abundant in the marine environment. One of such marine viruses, the white spot syndrome virus (WSSV), has emerged globally as one of the most prevalent, widespread and lethal for shrimp populations. However, at present there is no treatment available to interfere with the unrestrained occurrence and spread of the disease. The recent progress in molecular biology techniques has made it possible to obtain information on the factors, mechanisms and strategies used by this virus to infect and replicate in susceptible host cells. Yet, further research is still required to fully understand the basic nature of WSSV, its exact life cycle and mode of infection. This information will expand our knowledge and may contribute to developing effective prophylactic or therapeutic measures. This review provides a state-of-the-art overview of the topic, and emphasizes the current progress and future direction for the development of WSSV control strategies
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients.
OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs.
DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification.
PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries.
MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes.
RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure.
CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p
Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study
BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223
Distribución, incidencia y transmisión del virus del síndrome de la mancha blanca (WSSv) del camarón blanco del Pacífico (Litopenaeus vannamei) cultivado en el noroeste de México
Evaluation of a detection system of yellow head disease virus (YHV) using q-PCR
Yellow head disease is caused by the yellow head virus (YHV). This important
disease affects Penaus monodon farms in Thailand. In Mexico, reports of this
disease in L. vannamei have been issued. This has not been officially
declared by the World Organization for Animal Health (OIE). This study
reports a method of reverse-transcription polymerase chain reaction for the
detection of this virus in shrimp. A certified sample was analyzed with a
commercial detection system for YHV. We obtained a differential sequence of
genotypes that cause both YHV and gill-associated virus (GAV) by comparison
with ClustalW. Primers were designed for amplification of the fragment by a
TaqMan probe with which a positive standard to YHV was amplified. Tests were
negative for other pathogens. A survey of shrimp farms in Mexico in 2009
showed negative results for YHV presence. These results demonstrate that the
system developed in this study is a specific diagnostic method, sensitive and
reproducible for detection of YHV