Individualizing mechanical ventilation: titration of driving pressure to pulmonary elastance through Young's modulus in an acute respiratory distress syndrome animal model

Background

Mechanical ventilation increases the risk of lung injury (VILI). Some authors propose that the way to reduce VILI is to find the threshold of driving pressure below which VILI is minimized. In this study, we propose a method to titrate the driving pressure to pulmonary elastance in an acute respiratory distress syndrome model using Young’s modulus and its consequences on ventilatory-induced lung injury.

Material and methods

20 Wistar Han male rats were used. After generating an acute respiratory distress syndrome, two groups were studied: (a) standard protective mechanical ventilation: 10 rats received 150 min of mechanical ventilation with driving pressure = 14 cm H₂O, tidal volume < 6 mL/kg) and (b) individualized mechanical ventilation: 10 rats received 150 min of mechanical ventilation with an individualized driving pressure according to their Young’s modulus. In both groups, an individualized PEEP was programmed in the same manner. We analyzed the concentration of IL-6, TNF-α, and IL-1ß in BAL and the acute lung injury score in lung tissue postmortem.

Results

Global driving pressure was different between the groups (14 vs 11 cm H2O, p = 0.03). The individualized mechanical ventilation group had lower concentrations in bronchoalveolar lavage of IL-6 (270 pg/mL vs 155 pg/mL, p = 0.02), TNF-α (292 pg/mL vs 139 pg/mL, p < 0.01) and IL-1ß (563 pg/mL vs 131 pg/mL, p = 0.05). They presented lower proportion of lymphocytes (96% vs 79%, p = 0.05) as well as lower lung injury score (6.0 points vs 2.0 points, p = 0.02).

Conclusion

In our model, individualization of DP to pulmonary elastance through Young’s modulus decreases lung inflammation and structural lung injury without a significant impact on oxygenation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04184-w.

Flexible ureteroscopy without ureteral access sheath

INTRODUCTION

Ureteral access sheath (UAS) is widely used in flexible ureteroscopy and laser lithotripsy (FURS) based on better stone-free rates, lower intrarenal pressure and fewer complications. However, it also rises surgical costs and may injure the ureteral wall. The main objective of our study is to compare safety and efficacy of FURS with and without UAS to evaluate whether its use is justified in all cases.

MATERIALS AND METHODS

We performed a retrospective observational analytic study based on a prospective database. A total of 241 consecutive patients who underwent FURS for upper ureter and renal stones between January 2018 and May 2020 were included for analysis and divided into two groups upon UAS use. We compared demographic data, stone characteristics, prestenting, operative time, need for ureteral stent, postoperative urinary tract infection, renal colic and need for ancillary procedures.

RESULTS

A total of 198 patients (82.2%) were included in the group without UAS. Operative time was significantly shorter in the group of patients without UAS than those with UAS (64.6 minutes ± 29.5 vs. 89.9 minutes ± 2.8 respectively; p 0.010). Both groups had similar rates of colic pain and urinary tract infection. Ancillary procedures were more frequent in the UAS group (37.2 vs. 21.2%; p 0.026), but significance was lost in multivariate assessment.

CONCLUSION

FURS without UAS seems to be as safe as FURS with UAS but requires less ancillary procedures. An additional advantage is shorter operative time.

Safety and efficacy evaluation of the automatic stepwise recruitment maneuver in the neonatal population: An in vivo interventional study. Can anesthesiologists safely perform automatic lung recruitment maneuvers in neonates?

BACKGROUND

A new software has recently been incorporated in almost all new anesthesia machines to enable automatic lung recruitment maneuvers. To date, no studies have assessed the safety and efficacy of these automatic software programs in the neonatal population.

AIMS

We aimed to evaluate the safety and efficacy of the lung recruitment maneuver performed using the automatic stepwise recruitment maneuver software of the FLOW-i 4.3 Anesthesia System^® in a healthy and live neonatal model.

METHODS

Eight male newborn piglets were included in the study. The lung recruitment maneuver was performed in pressure-controlled ventilation with a constant driving pressure (15 cmH₂ O) in a stepwise increasing positive end-expiratory pressure (PEEP) model. The target peak inspiratory pressure (PIP) was 30 cmH₂ O and PEEP was 15 cmH₂ O. The maneuver lasted for 39 seconds. The hemodynamic variables were monitored using the PICCO^® system. The following respiratory parameters were monitored: oxygen saturation, fraction of inspired oxygen, partial pressure of oxygen and carbon dioxide in the arterial blood, end-tidal carbon dioxide pressure, PIP, plateau pressure, PEEP, static compliance (C_stat ), and dynamic compliance (C_dyn ). Safety was evaluated by assessing the accuracy of the software, need for not interrupting the maneuver, hemodynamic stability, and absence of adverse respiratory events with the lung recruitment maneuver. Efficacy was evaluated by improvement in C_stat and C_dyn after performing the lung recruitment maneuver.

RESULTS

All lung recruitment maneuvers were safely performed as scheduled without any interruptions. No pneumothorax or other side effects were observed. Hemodynamic stability was maintained during the lung recruitment maneuver. We observed an improvement of 33% in C_dyn and 24% in C_stat after the maneuver.

CONCLUSIONS

The automatic stepwise recruitment maneuver software of the FLOW-i 4.3 Anesthesia System^® is safe and efficacious in a healthy neonatal model. We did not observe any adverse respiratory or hemodynamic events during the implementation of the lung recruitment maneuver in the pressure-controlled ventilation mode using a stepwise increasing PEEP (30/15 cmH₂ O) approach.

New indicators for optimal lung recruitment during high frequency oscillator ventilation

Previous research has demonstrated the potential benefit derived from the combination of high frequency oscillatory ventilation and volume guarantee mode (HFOV-VG), a procedure that allows us to explore and control very low tidal volumes. We hypothesized that secondary spontaneous change in oscillation pressure amplitude (∆Phf), while increasing the mean airway pressure (MAP) using HFOV-VG can target the lung recruitment.

METHODS

A two-step animal distress model study was designed; in the first-step (ex vivo model), the animal's lungs were isolated to visually check lung recruitment and, in the second one (in vivo model), they were checked through arterial oxygen partial pressure improvement. Baseline measurements were performed, ventilation was set for 10 min and followed by bronchoalveolar lavage with isotonic saline to induce depletion of surfactant and thereby achieve a low compliance lung model. The high-frequency tidal volume and frequency remained constant and the MAP was increased by 2 cmH₂ O (ex vivo) and 3 cmH₂ O steps (in vivo) every 2 min. Changes in ΔPhf to achieve the fixed volume were recorded at the end of each interval to describe the maximum drop point as the recruitment point.

RESULTS

Fourteen Wistar Han rats were included, seven on each sub-study described. After gradual MAP increments, a progressive decrease in ΔPhf related to recruited lung regions was visually demonstrated. In the in vivo model we detected a significant comparative decrease of ΔPhf, when measured against the previous value, after reaching a MAP of 11 cmH₂ O up to 17 cmH₂ O, correlating with a significant improvement in oxygenation.

CONCLUSION

The changes in ∆Phf, linked to a progressive increase in MAP during HFOV-VG, might identify optimal lung recruitment and could potentially be used as an additional lung recruitment marker.

[Management of malignant ureteral obstruction.]

OBJECTIVE

To describe the different therapeutic alternatives in malignant ureteral obstruction (MUO), and to analyze short and long-term results.

METHODS

We conducted a bibliographic search about MUO in Spanish and English languages in PubMed and Google Scholar. We examined the most relevant reviews, original manuscripts and their respective citations. Last search was on April 2016.

RESULTS

Polymeric double J stent is the cheapest and most accessible internal urinary diversion, but has also the shortest duration. Early and late failure rates were 0-35% and 14-49% respectively. Mean time to late failure was 3-12 months. Percutaneous nephrostomy is the safest alternative in terms of failure rates, though it has frequent complications such as tube dislodgement, and may have a negative effect on quality of life. The only metallic double J stent with enough bibliographic background is the Resonance® stent. Early failure was 0-15% and late failure 4-41%, with a mean time to late failure of 2.6-13 months. Regarding metallic stents, Memokath 051® has obtained the best results, with 0-5% early failure rates, 19-49% late failures and mean time to late failure of 7-11 months. In patients with polymeric double J stent failure, patients benefited from tandem double J stents, metallic double J catheters or metallic stents, avoiding the need of a percutaneous nephrostomy. The evidence level was low in all cases.

CONCLUSIONS

Results in MUO are very heterogeneous and have a low evidence level. Factors that influence results include stent characteristics, status and prognosis of the obstructive condition and probably patient and physician's preferences. Polymeric double J stents seem to have higher early and late failure rates than metallic double J catheters and metallic stents. Even though, the difference is not clearly evident. Prospective, multicenter, multidisciplinary trials are necessary to elucidate convenience and adequate selection of each type of stent.

Effects of intramuscular alfaxalone alone or in combination with diazepam in swine

OBJECTIVE

To describe the use of intramuscular (IM) premedication with alfaxalone alone or in combination with diazepam in pigs.

STUDY DESIGN

Randomised-controlled trial.

ANIMALS

Twelve healthy 2 month-old Landrace x Large White pigs weighing 21.3 ± 2.4 kg.

METHODS

Animals were distributed randomly into two groups: group A (n = 6) 5 mg kg(-1) of IM alfaxalone; and group AD (n = 6) 5 mg kg(-1) of IM alfaxalone + 0.5 mg kg(-1) of IM diazepam mixed in the same syringe. The total volume of injectate was standardized at 14 mL by dilution in 0.9% sodium chloride. Pain on injection, the degree of sedation and the quality of and time to induction of recumbency were evaluated. Once pigs were recumbent, reflexes were evaluated. Pulse and respiratory rates and arterial oxygen saturation were recorded at 5 and 10 minutes after drug administration. Pigs were then moved to another room for subsequent anaesthesia.

RESULTS

Two animals of group A and one of group AD showed slight pain on drug injection. Time to lateral recumbency (in seconds) was shorter in group AD (mean 203 ± SD 45 range 140-260) than group A (302 ± 75, range 220-420; p < 0.05). In group AD sedation was deeper, and on recumbency there was better muscle relaxation. When moved for anaesthesia, two pigs in Group A showed slight resistance but did not vocalize. There were no differences in physiologic measurements between groups, although in both groups, respiratory rate was significantly lower at ten compared with five minutes post drug injection. There was no apneoa.

CONCLUSIONS AND CLINICAL RELEVANCE

IM administration of alfaxalone combined with diazepam resulted in a rapid onset of recumbency and deep sedation, with minimal side effects. The combination might be useful for premedication, but volume of injectate will limit its use to small pigs.

First Report of Powdery Mildew on Tomato Caused by Oidium neolycopersici in Venezuela

During 2004 and 2005, a powdery mildew was observed in tomato (Lycopersicon esculentum Mill. cv. Rio Grande) fields in several states in Venezuela. Symptoms included development of patches of dense white mycelium, predominantly on the upper leaf surface. Leaves in the middle and lower canopies were the most affected. Similar symptoms sometimes were observed on stems. The foliage of infected plants turned yellow and showed necrosis followed by desiccation and rapid defoliation. Microscopic examination revealed the presence of typical structures of the Oidium genus. Hyphae were hyaline and septate. Conidiophores were unbranched, erect, measured 51 to 108 (80) μm, and consisted of 3 or 4 cells. Conidia were hyaline, ellipsoidal to ovoidal, and measured 16 to 43 (30) × 12 to 22 (16) μm. Conidia were produced singly, without fibrosin bodies. Conidial polar germination was common. Appressoria were lobed. The sexual stage was not found. The fungus was identified as Oidium neolycopersici, recently recognized as a distinct species (1,2). Conidia from infected tomato leaves were shaken onto leaves of 10 plants of L. esculentum and L. pimpinellifolium (Jusl.) Mill. and five plants of a weed (Physalis peruviana L.). Noninoculated plants served as a control. Symptoms that developed on all inoculated plants were similar to those of plants naturally infected. Within 7 to 8 days, symptoms in L. esculentum consisted of small colonies that quickly covered large portions of foliar tissue. L. pimpinellifolium showed small and localized symptoms after 10 days and P. peruviana showed symptoms after 15 days. To our knowledge, this is the first report of O. neolycopersici in Venezuela. References: (1) H. Jones et al. Mol. Plant Pathol. 2:303, 2001. (2) L. Kiss et al. Mycol. Res. 105:684, 2001.

First Report of Exserohilum rostratum Associated with Rice Seed in Venezuela

Rice (Oryza sativa L.) is an important cereal crop in Venezuela and is planted on approximately 200,000 ha. Fungal diseases caused by the Helminthosporium complex of fungi are considered a major constraint to rice production. In 2005, a blotter method was used to identify fungi associated with rice seed. Seeds (150) of cv. INIA-017 were placed on a plate with moistened filter paper and incubated at 26 ± 2°C with a 12-h light/12-h dark cycle for 5 days until fungal sporulation. Single spores were transferred to 2% water agar (WA). Germinated spores were then transferred to potato dextrose agar (PDA), and resultant colonies were preserved until used. To induce sporulation, 4-mm-diameter discs were cut from 72-h-old cultures, transferred to WA, and incubated at 26 ± 2°C for 48 h (modified technique of Alcorn [1]). Discolored seed yielded isolates of Bipolaris oryzae (Berda de Haan) Shoemaker and Exserohilum rostratum (Drechs.) Leonard and Suggs (2). Pathogenicity tests were performed on 60-day-old rice plants of cv. Blue Bonnet 50. Four plants per pot were used for each isolate. Before inoculation, plants were placed in humidity chambers for 48 h. Spores were harvested from discs into a beaker containing 50 mL of a dilute gelatin solution (Gelatin Difco; 5 g/100 mL of sterile distilled water [SDW]). Spore suspensions were filtered through cheesecloth and adjusted to 7 × 10⁴ spores per ml. The inoculated plants were placed in humidity chambers for 72 h. Control plants were sprayed with SDW. Inoculated plants were removed from humidity chambers and placed on a greenhouse bench. Plants inoculated with B. oryzae were symptomatic 5 days after inoculation; resultant lesions were red-brown with chlorotic borders. Lesions subsequently turned gray with reddish borders and were rhombic in shape. Plants inoculated with E. rotratum were symptomatic 7 days after inoculation with elliptical lesions that were orange-brown along venation. These lesions turned gray with reddish borders. Both fungi were reisolated from symptomatic leaf tissue. To our knowledge, this is the first report of E. rostratum from rice in Venezuela. References: (1) J. L. Alcorn. Mycotaxon. 17:1, 1983. (2) A. Sivanesam. Mycol. Pap. 158, 1987.

Structure-based assessment of BRCA1 and BRCA2 mutations in a small Spanish population

Breast cancer is the most frequent cancer type among women in the world. There is abundant evidence, that alterations in the breast cancer susceptibility genes, BRCA1 and BRCA2, are present in a large proportion of families with multiple cases of breast and ovarian cancer. Our aim was to better understand the molecular and structural insights associated with the most frequent alterations, found in the BRCA1 and BRCA2 genes, within our patients. We analyzed 50 breast cancer cases. Of those, 24% were found to carry deleterious mutations, and up to 10 rare variants of unknown significance were detected. The frequency of polymorphic changes was considerably different between genes, BRCA1 (55%) and BRCA2 (19.4%). By looking at the protein level, the changes observed within the BRCA1 and BRCA2 genes could affect not only the nucleic location of the protein but also disrupt the folding and, therefore, the tumor suppressor function.

First Report of Guignardia psidii, an Ascigerous State of Phyllosticta psidiicola, Causing Fruit Rot on Guava in Venezuela

During August 2003, guava fruit (Psidium guajava L.) cv. Red Dominicana from Cojedes state in Venezuela showed circular, purple-to-brown lesions (0.5 to 1.0 cm) that spread over all surfaces and became black and shrunken on severely affected fruit. Symptomatic tissues were plated aseptically on potato dextrose agar (PDA). Colonies that were initially gray and turned black with age were consistently isolated. The fungus was characterized by dense, submerged, brown-to-black mycelium with septate hyphae. Ascocarps were perithecial, abundant, granulose, subglobose to cylindric obpyriform, solitary or aggregated, mostly unilocular with prominent long necks; ascocarp walls were stromatic, composed of several layers of cells, thick walled, and deeply pigmented on the outside. Asci were subclavate to cylindrical, stipitate, 44 to 84 × 7 to 9 μm, and eight-spored; asci walls were thick and bitunicate. Ascospores were unicellular, hyaline, guttulate, fusiform ellipsoid, widest in the mid-region with rounded ends and gelatinous plugs, and 12 to 17 × 4.5 μm. Conidiomata were pycnidial, intermixed among ascocarps, variable in shape, dark brown, solitary or aggregated, ostiolate, and with long necks up to 1 mm. Pycnidial walls were pseudoparenchymatic, multicellular, and composed of many layers of brown compressed cells. Conidiogenous cells were hyaline, subglobose to cylindrical, and smooth, and holoblastic. Conidia were hyaline, unicellular, obovate, 6 to 12 (7.5) × 5 to 8 μm, slightly truncate at the bases, rounded at apices, guttulate, and provided a gelatinous envelope and apical appendage. Appendages were hyaline, tubular, smooth, and 3.0 to 4.5 × 0.5 μm. The fungus is homothallic because single ascospores and single conidia developed ascigerous states. The ascigerous state was identified as Guignardia psidii (1) and the anamorph as Phyllosticta psidiicola (1,2). Pathogenicity tests were conducted on detached fruits inoculated with monosporic cultures. Pathogenesis and symptom development only occurred when a mixture of mycelium, ascospores, and conidia was used as inoculum. The fungus was reisolated from symptomatic fruit tissues. To our knowledge, this is the first report of Guignardia psidii, an ascigerous state of Phyllosticta psidiicola from guava fruits in Venezuela. References: (1) B. A. Ullasa and R. D. Rawal. Curr. Sci. 53:435, 1984. (2) H. A. van der Aa. Page 95 in: No. 5, Stud. Mycol., 1973.

Effect of troglitazone on the desaturases in a rat model of insulin-resistance induced by a sucrose-rich diet

A sucrose-rich diet generates time-dependent metabolic disorders similar to those found in diabetes type 2. After 8 month (mo) this diet evoked in the rat an increase of blood glucose, free fatty acids (FFA) and triacylycerides (TG) without insulin modification, an interruption of liver stearoyl-CoA desaturase-1 (SCD-1) mRNA and activity increase found at 6 mo, and an enhacement of Delta6 and Delta5 desaturase mRNA and Delta6 activity. We found that the administration of troglitazone (TRO), a peroxisome-proliferator-activated receptors gamma (PPAR-gamma) agonist, for 2 mo normalized plasma FFA, TG, and glucose without altering the insulinemia. It depressed liver SCD-1 mRNA in both control and sucrose-fed rats, decreasing the 18:1n-9/18:0 ratio in serum and liver lipids, and eliminated the increasing effect on mRNA and activity of Delta6 and Delta5 desaturases. These findings evidence again that desaturases are not affected through an insulin resistant effect evoked by the sucrose-rich diet and TRO recovers the altered metabolic plasma parameters as it corresponds to a PPAR-gamma agonist, but its effect on hepatic desaturases can not be attributed to a direct action on liver by PPAR-gamma, insulin, and even by an insulin sensitizing mechanism, suggesting it would be evoked indirectly through hepatic PPAR-alpha deactivation induced by the FFA decrease.

First Report of Fusarium denticulatum from Sweet Potato in Venezuela

During 2001and 2002, 53 accessions of sweet potato (Ipomoea batatas L.) from a germ plasm collection maintained in the field at Centro Nacional de Investigaciones Agropecuarias, Maracay, Venezuela, were evaluated for diseases. Sweet potato accessions Catemaco and 2878 were symptomatic for chlorotic leaf distortion with deformation of young leaves and stunted vines. Symptomatic nodes and shoot tips were excised, surface disinfested in 0.5% sodium hypochlorite, cultured on potato dextrose agar (PDA), and incubated at 28°C. Pale pink colonies with white aerial mycelium developed from symptomatic tissues. At 20°C, pure cultures on PDA developed slow-growing, aerial, white-to-pink mycelium. Pigmentation in reverse was light orange. Conidia aggregated in false heads, and orange sporodochia were abundant. Conidiophores in aerial mycelium were prostrate, short, and sometimes branched. Sporodochial conidiophores were branched. Phialides were mostly monophialidic but occasionally polyphialidic and averaged 25.0 × 3.0 µm. Microconidia were abundant, long, oval to allantoid, and 0 to 1 septate. Macroconidia were fusiform to falcate with a beaked apical cell and a footlike basal cell, 3 to 5 sepate, and 38 to 45 × 3.6 to 4.0 µm. Chlamydospores were absent. The fungus was identified as Fusarium denticulatum Nirenberg and O'Donnell (1). Ten 25-cm-long vine-tip cuttings of accessions Catemaco and 2878 were immersed in a conidial suspension (1 × 10⁶ conidia per ml) of F. denticulatum. As a control, vines were immersed in sterile, distilled water. After inoculation, each cutting was planted in a 13-cm plastic pot containing a soil/sand (1:1) mixture. Inoculated plants were covered with plastic bags for 48 h and grown in a greenhouse at temperatures ranging from 30 to 38°C. After 3 months, three inoculated plants of accession Catemaco and two plants of accession 2878 developed purple terminals and moderate interveinal chlorosis. Leaf distortion was not observed. F. denticulatum was recovered from both symptomatic and asymptomatic inoculated plants. To our knowledge, this is the first report of F. denticulatum from sweet potato germ plasm in Venezuela. Dried, pure cultures and slides of the fungus are being deposited in the Albert S. Muller Herbario Micologico (VIA). Reference: (1) H. I. Nirenberg and K. O'Donnell. Mycologia 90:434, 1998.

Immunohistochemical detection of a very high density lipoprotein (VHDL) in ovarian follicles of Triatoma infestans

The ability of Triatoma infestans ovarian follicles to synthesize a very high-density lipoprotein (VHDL) has been examined by immunohistochemical methods. This kind of lipoprotein can be envisaged as a storage hexameric protein present in the hemolymph of some insect species. VHDL immunoreactivity is observed in oocytes at different stages of maturation. The antigen is present in the oocyte cytoplasm as well as in the follicular epithelial cells. The immunopositive reaction in the apical surface of follicle cells suggests both a VHDL synthesis and a secretion process. Furthermore, VHDL seems to be stored into oocyte in yolk granules. On the contrary, no immunopositive reaction is observed in the intracellular spaces between follicle cells, suggesting that VHDL is not incorporated from hemolymph into the oocyte.

Fatty acid delta9-desaturation in the Triatoma infestans fat body: response to food and trehalose administrations

The effects of food intake and carbohydrate administration on fatty acid delta9-desaturation were investigated in isolated microsomes from Triatoma infestans fat body. Fifth instar nymphs, which were solely blood-fed just after the molt and then fasted, were used as controls and for determination of optimal assay conditions. Both [1-14C]palmitic and [1-14C]stearic acids in a medium containing ATP, CoA, MgCl2, NADH, NaF, and O2 were tested. For the control group, optimal conditions were a pH of 6.8-7.2, an incubation temperature of 29 degrees C, and an incubation time of 10 min. delta9-Desaturation depended on the presence of reduced pyridine dinucleotides; NADH and NADPH were equally efficient. Stearic acid showed a higher apparent Vmax than palmitic acid, but the apparent Km were very similar. When fifth instar nymphs were blood-fed weekly, a marked increase of delta9-desaturation was observed for both acids. Higher desaturation activity was also induced by injection of the carbohydrate trehalose into the hemolymph of fasted nymphs. These results indicate that insect delta9-desaturation, like the mammalian counterpart, is sensitive to dietary changes and carbohydrate administration.

Biochemistry of the evolution of Triatoma infestans. XII. Biosynthesis and secretion of a very high density lipoprotein

Biosynthetic processes related to the production of an insect hexamerin, very high density lipoprotein (VHDL), have been examined in the fat body of fifth-instar nymph and adult Triatoma infestans. Fat bodies were incubated in vitro with [3H]leucine and the incubation media were precipitated using a specific antiserum. The SDS-polyacrylamide gel electrophoresis followed by blotting on nitrocellulose showed that both larval and adult fat body secreted the VHDL subunit. Moreover, the radiolabel recovered in this subunit is indicative of the de novo synthesis. When the incubation medium was subjected to density gradient ultracentrifugation, a radiolabeled fraction was found at density 1.27 g/ml, value identical to the hemolymph circulating VHDL, indicating that the secreted apoprotein is combined with lipids. The SDS-polyacrylamide gel electrophoresis and immunoblotting of this fraction corroborated the presence of the VHDL-apoprotein. These results demonstrate that the fat body of T. infestans is able to synthesize the protein subunit which is associated to lipids as a lipoprotein particle that is released into the medium as VHDL.

Detection and quantification of a very high density lipoprotein in different tissues of Triatoma infestans during the last nymphal and adult stages

The presence of a very high density lipoprotein (VHDL), an hexameric protein, was explored in different tissues of Triatoma infestans throughout the last nymphal and adult stages, and in egg extracts by Western blot assays. The VHDL was always detected in both, hemolymph and fat body, during the above mentioned stages and it was also observed in the buffer soluble fraction of testis and egg homogenates. An enzyme-linked immunosorbent assay (ELISA) was used to measure the VHDL titer in these tissues. Hemolymph VHDL reaches a maximum value before the last molt, then it abruptly declines in males and females just after emergence, but during adult life it increases again. Fat body VHDL decreases slowly and continuously during the nymph growth reaching a minimum value prior to molting, and in the first week of adult life the values were even two-fold lower; then, it shows a different cycle of accumulation and depletion in males and females. In adult testis the VHDL undergoes a cycle similar to the one observed in male fat body. This protein increases progressively during embryonic development and, at the time of larval hatching it reaches its maximum value. The hexameric protein presents homologies in its N-terminal sequence with storage hexamerins of Diptera, Lepidoptera and Hymenoptera.

[Classification and frequency of patients with cleft lip and palate in a hospital institution]

A review of case histories of patients with cleft lip and/or cleft palate from the Department of Stomatology of the Federico Gómez Children's Hospital in Mexico City, rounded as preliminary material for starting a statistical record, classifying cases as to severity and schedule them for consultation, in order to provide them a better orthodontic attention.

Flavonoids from Chenopodium botrys

From Chenopodium botrys, five flavonoids have been isolated: hispidulin, 1, salvigenin 2, 5-methylsalvigenin, 3, 7-methyleupatulin, 4 and sinensetin, 5. None of them have been previously reported from Ch. botrys.