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1.
J Clin Med ; 13(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38592078

RESUMO

Introduction: A substantial percentage of patients undergoing bariatric surgery are of childbearing age. Pregnancy outcomes after bariatric surgery are known. However, there are limited data on the impact of pregnancy on weight loss after surgery. Objectives: This study aims to evaluate the effects of pregnancy on post-bariatric surgery weight loss trajectories (WLTs) and to determine the association with age and initial weight. Methods: All who had primary bariatric surgeries (Roux-en-Y gastric bypass or sleeve) between September 2015 and July 2020 were classified into two groups: post-surgery gravid (GG) and post-surgery non-gravid (NG). WLTs were examined using a random intercept mixed-effects model with repeated measures nested within patients. The post-surgery/pre-gravid time phase (PoPG) was modelled using a third-degree polynomial. For GG, two third-degree spline functions modelled the post-surgery while gravid (PoWG) and post-partum (PoPP) time phases. Age and initial weight were used to control for pre-existing differences during PoPG. Weight differences at 6 months PoPP were examined by applying general linear hypothesis testing to the mixed-model results. Results: A total of 508 patients were included, 20 in GG and 488 in NG. The mean age at surgery was 33 years in GG and 37 years in NG. The mean initial BMI was 47 kg/m2 and 43 kg/m2, respectively. During PoPG, adjusted average weight in both groups follows the path across time. For GG, weight decreases and then increases during PoWG. For GG during PoPP, weight immediately decreases after delivery and then increases over time to levels similar to NG. Weight differences at 6 months PoPP for GG and NG were not statistically different. Older age was associated with reduced weight loss during PoPG by Baseline Age, while higher initial weight was associated with increased weight loss during PoPG by Baseline Weight. In both instances, these effects attenuate over time. Conclusions: This model indicates that pregnancy following bariatric surgery affects WLT during PoWG and PoPP, and no difference in weight is expected after 6 months post-gravid. Age and initial weight could be considered prognostic factors during PoPG. Patients wishing to conceive should undergo preconception counselling and be advised to avoid pregnancy during the period of rapid weight loss. They also should be informed that WLT may vary during pregnancy and early post-partum.

2.
Surg Endosc ; 32(4): 1820-1827, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28932941

RESUMO

INTRODUCTION: This study aims to evaluate the outcomes and utilization of porcine acellular dermal collagen implant (PADCI) during VHR at a large tertiary referral center. METHODS: Records of 5485 patients who underwent VIHR from June 1995 to August 2014 were retrospectively reviewed to identify patients >18 years of age who had VIHR with PADCI reinforcement. Use of multiple mesh reinforcement products, inguinal hernias, and hiatal hernias were exclusion criteria. The primary outcome was hernia recurrence, and secondary outcomes were early complications and surgical site occurrences (SSOs). Uni- and multivariate analyses assessed risk factors for recurrence after PADCI reinforced VIHR. RESULTS: There were 361 patients identified (54.5% female, mean age of 56.7 ± 12.5 years, and mean body mass index (BMI) of 33.0 ± 9.9 kg/m2). Hypertension (49.5%), diabetes (24.3%), and coronary artery disease (14.4%) were the most common comorbidities, as was active smoking (20.7%). Most were classified as American Association of Anesthesiologists (ASA) Class 3 (61.7%). Hernias were distributed across all grades of the ventral hernia working group (VHWG) grading system: grade I 93 (25.7%), grade II 51 (14.1%), grade III 113 (31.3%), and grade IV 6 (1.6%). Most VIHR were performed from an open approach (96.1%), and were frequently combined with concomitant surgical procedures (47.9%). Early postoperative complications (first 30 days) were reported in 39.0%, with 71 being SSO. Of the 19.7% of patients with SSO, there were 31 who required procedural intervention. After a mean follow-up of 71.5 ± 20.5 months, hernia recurrence was documented in 34.9% of patients. Age and male gender were predictors of recurrence on multivariate analysis. CONCLUSION: To the best of our knowledge, this is the largest retrospective single institutional study evaluating PADCI to date. Hernias repaired with PADCI were frequently in patients undergoing concomitant operations. Reinforcement with PADCI may be considered a temporary closure, with a relatively high recurrence rate, especially among patients who are older, male, and undergo multiple explorations in a short perioperative period.


Assuntos
Hérnia Ventral/cirurgia , Herniorrafia , Derme Acelular , Adulto , Idoso , Animais , Colágeno , Feminino , Herniorrafia/métodos , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Telas Cirúrgicas/efeitos adversos , Suínos , Resultado do Tratamento
3.
Clin Obstet Gynecol ; 60(2): 245-251, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28288013

RESUMO

Endometriosis is a common disease affecting reproductive age women. Pain is one of the most common symptoms associated with endometriosis. When medical therapy has failed or in known deeply infiltrating endometriosis, surgical management is warranted. Laparoscopy is the gold standard for diagnosis and treatment of endometriosis. Recent developments in surgery have shown the feasibility of robotic surgery for endometriosis, although these methods have not been shown to be superior to conventional laparoscopy. Enhanced imaging techniques including fluorescence imaging and narrow band imaging have also been studied. However, long-term clinical benefits have yet to be demonstrated.


Assuntos
Endometriose/cirurgia , Dor Pélvica/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Feminino , Humanos , Laparoscopia , Dor Pélvica/etiologia , Procedimentos Cirúrgicos Robóticos/tendências
5.
J Minim Invasive Gynecol ; 24(2): 194-195, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27856388

RESUMO

STUDY OBJECTIVE: To show a new technique for bilateral salpingectomy using percutaneous minilaparoscopy. DESIGN: Step-by-step video demonstration and narration of the surgical procedure. SETTING: Minilaparoscopy was first described in the late 1980s and early 1990s. Since then, minilaparoscopic instruments have been successfully applied to several general surgery and gynecologic procedures, including hysterectomy. Potential benefits of minilaparoscopy compared with conventional laparoscopy include decreased tissue trauma, pain, and improved cosmesis. INTERVENTIONS: Percutaneous minilaparoscopic approach for bilateral salpingectomy. CONCLUSION: Percutaneous minilaparoscopy, in addition to conventional laparoscopy, is a feasible approach for bilateral salpingectomy.


Assuntos
Laparoscopia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Salpingectomia/métodos , Adulto , Estudos de Viabilidade , Feminino , Humanos , Histerectomia/instrumentação , Histerectomia/métodos , Laparoscopia/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Salpingectomia/instrumentação
6.
Int J Obes (Lond) ; 41(3): 443-449, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27881858

RESUMO

BACKGROUND: Bariatric surgery is performed safely in non-alcoholic fatty liver disease (NAFLD) patients with minimal fibrosis (stage 1-2). However, the safety and potential benefits of bariatric surgery for NAFLD with advanced fibrosis (stage 3-4) remain unclear. This study was designed to compare the safety and efficacy of bariatric surgery in patients with biopsy proven advanced fibrosis to those with minimal fibrosis. METHODS: All patients who underwent bariatric surgery between 2005 and 2014 and had evidence of NAFLD with fibrosis score 3-4 (advanced fibrosis) based on the staging system defined by Kleiner et al. on intraoperative liver biopsy were included and compared with patients who had fibrosis score 1-2 (minimal fibrosis). The groups were compared for length of hospital stay after bariatric surgery and incidence of postoperative complications over a follow-up period of 1 year. An improvement in hepatic function tests before and 1 year after surgery was used as a parameter to evaluate for NAFLD improvement. RESULTS: Ninety-nine patients with F3-4 (group 1) and 198 patients with F1-2 (group 2) were included. Mean age (51.9 vs 50.1 years) and body mass index (46.4 vs 46.5 kg m-2) were similar in the two groups. Median serum aspartate aminotransferase (43 vs 30 U l-1; normal 10-40 U l-1) and alanine aminotransferase (40.5 vs 34 U l-1; normal 10-50 U l-1) were significantly higher in group 1 and improved 1 year after surgery. Median length of hospital stay after surgery was higher in group 1 than that in group 2 (4 days vs 3 days; P-value=0.002). The proportion of patients developing postoperative complications over 1 year was similar in both groups (36.4% vs 32.8%; P-value=0.54). CONCLUSIONS: Advanced fibrosis does not increase the risk of developing postoperative complications in medically optimized patients undergoing bariatric surgery. Improvement in serum transaminase levels suggests a reduction in hepatic necroinflammatory activity following bariatric surgery.


Assuntos
Cirurgia Bariátrica , Inflamação/patologia , Tempo de Internação/estatística & dados numéricos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/patologia , Alanina Transaminase/sangue , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Biomarcadores/sangue , Biópsia , Medicina Baseada em Evidências , Feminino , Seguimentos , Humanos , Inflamação/epidemiologia , Inflamação/etiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade Mórbida/complicações , Obesidade Mórbida/patologia , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Índice de Gravidade de Doença , Estados Unidos
7.
Surg Endosc ; 31(4): 1573-1582, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27495345

RESUMO

BACKGROUND: Currently there is no consensus on management of ventral hernias encountered during bariatric surgery (BS). This study aims to evaluate the incidence and outcomes of concomitant ventral hernia repair (VHR) during BS at our institution. METHODS: Patients who had concomitant VHR during BS from 2004 to 2015 were identified. Data collected included baseline demographics, comorbidities, perioperative parameters, surgical approach and postoperative outcomes. RESULTS: A total of 159 patients underwent concomitant VHR during the study period at the time of BS. One hundred and one (64 %) patients were female; median age was 53 years (IQR 45.0-60.3) and median BMI was 48.2 kg/m2 (IQR 41.6-54.1). Comorbidities included: hypertension (n = 124, 78 %), type 2 diabetes (n = 103, 65 %), hyperlipidemia (n = 100, 63 %), obstructive sleep apnea (n = 98, 62 %) and reflux disease (n = 54, 34 %). Out of 159 patients, 41 patients (26 %) had a prior VHR. Out of 103 patients, 69 patients (67 %) had a previous abdominal surgery. Of the concomitant VHR, 144 (91 %) were completed laparoscopically, 12 (7 %) patients were converted to open surgery and 3 (2 %) patients underwent primary open procedures. Technique included primary suture closure in 115 (72 %) and mesh repair in 44. Early postoperative complications (<30 days) were reported in 16 (10 %) patients, with superficial wound infection (n = 9), bowel obstruction (n = 2), marginal ulcer (n = 2), DVT (n = 1) and pneumonia (n = 1). Hernia recurrence was reported in 3 patients (2 %) in the early post-op period and in 40 patients (25 %) as a late (>30 days) complication. Surgery for recurrent hernia was performed in 31/42 patients during follow-up. At 12-month follow-up, median BMI and % excess weight loss were 34.2 kg/m2 (IQR 29.5-40.9) and 59.6 % (IQR 44.9-74.8 %), respectively. CONCLUSION: Ventral hernia is a common finding in patients undergoing BS. Both primary suture repair and mesh repair result in acceptable results, both in terms of recurrence and perioperative complications.


Assuntos
Cirurgia Bariátrica , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Laparoscopia , Complicações Pós-Operatórias/cirurgia , Adulto , Cirurgia Bariátrica/métodos , Comorbidade , Feminino , Humanos , Incidência , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas , Suturas , Resultado do Tratamento , Redução de Peso
8.
J Pediatr Adolesc Gynecol ; 28(6): e179-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26211932

RESUMO

BACKGROUND: Extraosseous Ewing sarcoma (ES) tumors presenting in the genitourinary tract are highly uncommon. Few cases of primary vulvar and vaginal cases of ES have been published. CASE: A 15-year-old adolescent presented with a bothersome 5-cm mass located on her left labium minorum. Following excision, a diagnosis of a primary ES was made. The patient was treated with multiagent chemotherapy and was doing well 20 months after treatment completion. SUMMARY AND CONCLUSION: Based on the few available case reports and our reported case, it appears that extraosseous ES arising in superficial sites such as the vulva have better prognosis and should be treated with complete excision and multiagent chemotherapy.


Assuntos
Sarcoma de Ewing/diagnóstico , Neoplasias Vulvares/diagnóstico , Adolescente , Tratamento Farmacológico , Feminino , Humanos , Prognóstico , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/cirurgia , Neoplasias Vulvares/tratamento farmacológico , Neoplasias Vulvares/cirurgia
9.
J Minim Invasive Gynecol ; 22(6S): S133-S134, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27678722
10.
J Gastrointest Surg ; 17(3): 461-70, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23288718

RESUMO

BACKGROUND: Gastric electrical stimulator (GES) implantation is effective in certain patients with gastroparesis; however, laparotomy is often employed for placement. The aim of this study is to review outcomes of patients who underwent laparoscopic GES therapy for diabetic and idiopathic gastroparesis at a large referral center. METHODS: Patients who underwent GES (Enterra Therapy System; Medtronic, Minneapolis, MN) implantation with subsequent interrogation and programming between March 2001 and November 2011 were analyzed. RESULTS: A total of 113 patients underwent GES placement or revision during the study period. One hundred eleven patients underwent primary GES at our institution, while two patients underwent GES generator revision at our institution. Primary operations were completed laparoscopically in 110 of 111 cases, with one conversion to laparotomy due to severe adhesions. At a mean follow-up of 27 months (1-113), symptom improvement was achieved in 91 patients (80 %) and was similar for both the diabetic and idiopathic subgroups. Need for supplemental nutrition (enteral and/or parental) decreased in both groups. CONCLUSIONS: GES placement is feasible using a laparoscopic approach. Medical refractory gastroparesis in the diabetic and idiopathic groups had significant symptom improvement with no difference between the two groups. Need for supplemental nutrition is decreased following GES.


Assuntos
Complicações do Diabetes/complicações , Terapia por Estimulação Elétrica , Gastroparesia/etiologia , Gastroparesia/terapia , Implantação de Prótese/métodos , Adulto , Diabetes Mellitus/sangue , Terapia por Estimulação Elétrica/efeitos adversos , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Neuroestimuladores Implantáveis/efeitos adversos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Obesidade Mórbida/complicações , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do Tratamento , Adulto Jovem
11.
Surg Endosc ; 26(12): 3541-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22648113

RESUMO

BACKGROUND: Despite technical refinements of percutaneous endoscopic gastrostomy (PEG) tube placement, complications such as early tube dislodgement remain relatively static. This study aimed to review the experience of a high-volume endoscopy center after the introduction of T-fastener placement in high-risk patients. METHODS: The authors retrospectively reviewed PEG placement from October 2010 to September 2011, when their group began to use T-fasteners selectively in high-risk patients. Patients deemed to have an increased risk for early tube dislodgement underwent T-fastener placement at the time of PEG placement. Patients with PEG alone were compared with patients who had PEG with T-fastener (PEG-T) placement. Statistical analysis was performed using SPSS version 18. RESULTS: During the study period, 195 patients underwent PEG placement. For 121 patients, PEG alone was performed, whereas PEG-T was performed for 74 patients. Six patients had tube dislodgement (five early, one late) in the PEG-T cohort versus none in the PEG-alone cohort (P = 0.003). The first patient underwent diagnostic laparoscopy with replacement gastrostomy 2 days after tube dislodgement and was noted to have no contamination, with direct apposition of the stomach to the abdominal wall from the T-fasteners. The subsequent four patients with early tube dislodgement underwent non-emergent PEG replacement in the endoscopy unit within 24 h after tube dislodgement. In the short-term follow-up period, no repeat dislodgements were noted. Early mortality in the entire cohort was experienced by 38 (19.5%) of the 195 patients. CONCLUSION: Placement of T-fasteners in high-risk patients may decrease overall morbidity if early tube dislodgement occurs. The findings show the safety of non-emergent endoscopic replacement of PEGs in certain patients. Early tube dislodgement may be a marker of overall mortality.


Assuntos
Gastroscopia , Gastrostomia/instrumentação , Gastrostomia/métodos , Idoso , Árvores de Decisões , Falha de Equipamento , Feminino , Gastroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos
12.
Surg Endosc ; 22(10): 2314-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18622539

RESUMO

BACKGROUND: Enteral feeding and gastric decompression devices are common in critical, terminal, and chronically ill patients. Percutaneous transesophageal gastrostomy (PTEG) is a nonsurgical technique that creates an esophagostomy and allows enteral access in patients with a hostile abdomen, altered gastric anatomy, massive ascites, and carcinomatosis. We review our indications, technical experience, complications, and short- and long-term quality of life (QOL) in patients that underwent the PTEG procedure. METHODS: Patients were terminally ill from advanced cancer requiring gastrointestinal decompression or had hostile abdomens needing long-term feeding access. The procedure is carried out by inserting a rupture-free balloon (RFB) into the cervical esophagus and utilizing transcutaneous ultrasound to puncture the balloon. A guide wire is passed through the needle into the balloon, followed by a dilator and sheath. The in-dwelling catheter is inserted through the sheath, which exits the esophagus, and resides in the stomach. Proper placement is confirmed by fluoroscopy. RESULTS: From December 2003 to January 2006, 17 patients were treated with PTEG. Except for two patients, all of the patients had advanced metastatic cancer. Presenting symptoms were nausea, vomiting, and dysphagia. Average age was 62.8 years, with nine men. Placement was successful in 16 patients (94%). There were no major complications and three minor complications (17.6%). Minor complications included two esophageal leaks at the catheter site and one catheter dislodgement. Seven patients (41.2%) died within 1 month after the procedure from their preexisting medical conditions. All patients were capable of being discharged from the hospital with adequate enteral access and gastrointestinal decompression. CONCLUSIONS: PTEG is a safe and effective method of enteral feeding and decompression in patients that have contraindications to standard enteral access. Appropriate patient selection and timing of PTEG placement is crucial for optimum benefit.


Assuntos
Ascite/cirurgia , Descompressão Cirúrgica/métodos , Obstrução da Saída Gástrica/cirurgia , Gastrostomia/métodos , Obstrução Intestinal/cirurgia , Esôfago , Feminino , Obstrução da Saída Gástrica/etiologia , Neoplasias Gastrointestinais/complicações , Humanos , Obstrução Intestinal/etiologia , Masculino , Pessoa de Meia-Idade
13.
Surg Endosc ; 22(11): 2498-502, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18322740

RESUMO

BACKGROUND: The optimal management of Barrett's esophagus, a precursor to esophageal adenocarcinoma, remains controversial. Current therapy includes surveillance and ablative or resection techniques of varying safety and efficacy. This study aimed to determine the feasibility of a new catheter-based, endoscopic water jet ablation technique. METHODS: A high-pressure flexible catheter that can be passed through the working port of a standard gastroscope was used. The catheter had micro-drilled holes on one side near the tip. A 1-cm water jet was delivered under foot pedal control and endoscopic view at pressures adjusted from 150 to 400 psi. After approval from the authors' Institutional Review Board, tissue segments from fresh esophagectomy specimens were ablated by the catheter without use of an endoscope. Using gross appearance and histologic analysis, variable ablation pressures and times were evaluated. RESULTS: Using variable pressures and times, 11 ablation sessions were performed: 5 for normal esophagus, 4 for normal stomach, and 2 across the gastroesophageal junction in the setting of Barrett's esophagus. Ablation pressures of 150 to 300 psi for 30 to 60 s resulted in selective ablation of mucosa with preservation of the submucosa and muscularis propria. The depth of the ablation was determined by gross inspection at the time of ablation and confirmed by histologic evaluation. There was no embedding of epithelial cells in the muscularis propria. In a single normal esophagus specimen, a jet applied at 400 psi for 120 s in a confined area resulted in gross perforation. CONCLUSION: Selective ablation of esophageal and gastric epithelium using a catheter-based water jet ablation technique is feasible. The preliminary data from this study investigating a nonendoscopic technique show that the mucosa can be removed with preservation of the underlying submucosa and muscular layers. Further studies are warranted that focus on defining more precisely the pressure and duration required for optimal results and the practical application of this technique endoscopically.


Assuntos
Técnicas de Ablação/instrumentação , Esôfago de Barrett/cirurgia , Água , Animais , Desenho de Equipamento , Esofagoscopia , Humanos , Técnicas In Vitro , Pressão , Instrumentos Cirúrgicos , Suínos
14.
Gesundheitswesen ; 67(8-9): 646-55, 2005.
Artigo em Alemão | MEDLINE | ID: mdl-16217719

RESUMO

While surveying actually measured body weight is largely impractical in national surveys, self-reported weight is a simple and inexpensive method of collecting data. Previous research shows that data on reported body weight are falsified by systematic mis-reporting. This bias is said to be the consequence of the sensitive nature of information on body weight. Numerous studies on survey response suggest that certain modes of data collection are more conducive than others for probing sensitive information. This paper investigates the effect of the anonymous interviews, characteristics of the interviewer and respondents' familiarity with the survey, as factors that may impinge on reported body weight. Findings of this paper show that refusals to state the body weight are rare. Moreover, characteristics of interviewers account for only a small fraction of the variance in reported body weight. Yet the hypothesis that the absence of an interviewer in self-administered interviews increases reported body weight can be confirmed. This interview effect, however, occurred in men only. On average, male respondents in anonymous interview settings report on a body weight which is 1 kg more than they would report in other settings. The repeated participation of respondents in the Socio-Economic Panel Study (SOEP) increases their reported body weight accuracy which suggests a positive panel effect on respondents' willingness to disclose sensitive information.


Assuntos
Peso Corporal , Coleta de Dados/métodos , Inquéritos Epidemiológicos , Autorrevelação , Autoavaliação (Psicologia) , Adolescente , Adulto , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Planta ; 166(3): 287-99, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24241509

RESUMO

Exocytosis occurring during deposition of secondary wall material was studied by freeze-fracturing ultrarapidly frozen non-plasmolyzed and plasmolyzed tobacco pollen tubes. The secondary wall of tobacco pollen tubes shows a random orientation of microfibrils. This was observed directly on fractures through the tube wall and indirectly as imprints of microfibrils on fracture faces of the plasma membrane of non-plasmolyzed tubes. About half of the plasmatic fracture faces from non-plasmolyzed and plasmolyzed pollen tubes carried hexagonal arrays of intramembraneous particles in between randomly distributed particles. Deposition of secondary wall material was often accompanied by an undulated plasma membrane and the presence of membrane-bound vesicles in invaginations of the plasma membrane, between the plasma membrane and secondary wall and-especially in plasmolyzed tubes-within the secondary wall of tube flanks and wall cap. The findings are discussed in connection with published schemes of membrane behaviour during exocytosis.

16.
Planta ; 154(3): 241-50, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-24276067

RESUMO

Tobacco pollen tubes grown in vitro and from pollinated tobacco styles were treated by chemical solvents to remove one or more of the following polysaccharides from the tube walls: pectin (ethylenediamine tetraacetic acid); hemicellulose (alkali); callose (alkali; potassium hypochlorite); cellulose (cuprammonium); and all polysaccharides with exception of cellulose (H2O2/glacial acetic acid). Both the inner tube wall, which we had regarded as the secondary wall, and the plugs contained, in addition to callose, microfibrils of cellulose and "non-cellulosic" microfibrils that had "pectin-like" properties. When using the expressions callosic or callose layer and callose plugs in reference to pollen tubes, one should realize that they do not imply the exclusive presence of callose in the inner tube wall layer and its localized thickenings.

17.
Arch Microbiol ; 113(1-2): 73-8, 1977 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-560834

RESUMO

Carbohydrate composition was determined in isolated cell walls of meiospores of Allomyces arbuscula after incubation for 15 min (encysted meiospores: cysts), 150 min (germlings: cysts + rhizoids) and 24 h (cysts + rhizoids + hyphae). The principal constituent in all cell wall samples is chitin, accounting for about 75% of the recovered carbohydrates. In addition, cell walls of all stages examined contain polysaccharides which release galactose, glucose, mannose, arabinose, xylose, fucose, and rhamnose on acid hydrolysis. While different developmental stages show minor quantitative changes in chitin, the ratio of galactose to glucose decreases sharply during differentiation of ungerminated cysts into germlings with rhizoids and hyphae. The increase in glucose is accompanied by a decrease in the amount of xylose and/or fucose and of galactose.


Assuntos
Carboidratos/análise , Quitridiomicetos/análise , Fungos/análise , Parede Celular/análise , Quitina/análise , Quitridiomicetos/crescimento & desenvolvimento , Galactose/análise , Glucosamina/análise , Glucose/análise , Esporos Fúngicos/análise , Esporos Fúngicos/crescimento & desenvolvimento
18.
Arch Microbiol ; 109(1-2): 37-43, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-986794

RESUMO

Development of haploid meiospores of Allomyces arbuscula into germling cells with rhizoids and hyphae was followed during incubation in complete growth medium. The surface structure of encysted meiospores, rhizoids and hyphae before and after extraction of amorphous materials with ethanolic KOH was studied by means of carbon-platinum replicas. After 2--3 min incubation in complete medium 10% of the meiospores were surrounded by a cell wall containing microfibrils embedded in a matrix. Structure of cell walls of encysted meiospores, rhizoids, and hyphae differ from one another by the location of amorphous materials and by the arrangement of chitin microfibrils.


Assuntos
Quitridiomicetos/crescimento & desenvolvimento , Fungos/crescimento & desenvolvimento , Parede Celular/ultraestrutura , Morfogênese , Esporos Fúngicos/crescimento & desenvolvimento
20.
Plant Physiol ; 46(1): 150-6, 1970 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16657408

RESUMO

Stigmatic exudate, a secretion product recovered from the upper surface of Lilium longiflorum pistils, has been examined. Over 99% of the exudate is accounted for as water, carbohydrate, and protein. Exclusive of water, 95% is a high molecular weight, protein-containing polysaccharide composed of galactose, arabinose, rhamnose, glucuronic acid, and galacturonic acid.Detached pistils supplied with myo-inositol-U-(14)C, myo-inositol-2-(3)H, d-glucose-1-(14)C, or l-proline-U-(14)C produce labeled stigmatic exudate. When myo-inositol is supplied, the exudate is rich in labeled arabinose and uronic acids, but some label also recycles through the hexose phosphate pool of secreting cells, causing label to appear in galactose and rhamnose residues. When glucose is provided, galactose is the major constituent labeled but all of the other carbohydrate constituents are also labeled. Proline produces a pattern very similar to that obtained with glucose.Stigmatic exudate also contains a small amount of low molecular weight carbohydrate. If myo-inositol is used to label exudate, free labeled myo-inositol cannot be detected in the low molecular weight fraction until it has been subjected to acid hydrolysis. Similarly, if d-glucose is the source of label, free labeled glucose is found in the low molecular weight fraction only after acid hydrolysis.

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