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1.
World J Surg ; 43(3): 659-695, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30426190

ABSTRACT

BACKGROUND: This is the fourth updated Enhanced Recovery After Surgery (ERAS®) Society guideline presenting a consensus for optimal perioperative care in colorectal surgery and providing graded recommendations for each ERAS item within the ERAS® protocol. METHODS: A wide database search on English literature publications was performed. Studies on each item within the protocol were selected with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohorts and examined, reviewed and graded according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. RESULTS: All recommendations on ERAS® protocol items are based on best available evidence; good-quality trials; meta-analyses of good-quality trials; or large cohort studies. The level of evidence for the use of each item is presented accordingly. CONCLUSIONS: The evidence base and recommendation for items within the multimodal perioperative care pathway are presented by the ERAS® Society in this comprehensive consensus review.


Subject(s)
Colon/surgery , Digestive System Surgical Procedures , Elective Surgical Procedures , Perioperative Care , Practice Guidelines as Topic , Rectum/surgery , Clinical Protocols , Digestive System Surgical Procedures/methods , Elective Surgical Procedures/methods , Humans , Perioperative Care/methods , Recovery of Function
2.
Acta Anaesthesiol Scand ; 60(3): 289-334, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26514824

ABSTRACT

BACKGROUND: The present interdisciplinary consensus review proposes clinical considerations and recommendations for anaesthetic practice in patients undergoing gastrointestinal surgery with an Enhanced Recovery after Surgery (ERAS) programme. METHODS: Studies were selected with particular attention being paid to meta-analyses, randomized controlled trials and large prospective cohort studies. For each item of the perioperative treatment pathway, available English-language literature was examined and reviewed. The group reached a consensus recommendation after critical appraisal of the literature. RESULTS: This consensus statement demonstrates that anaesthesiologists control several preoperative, intraoperative and postoperative ERAS elements. Further research is needed to verify the strength of these recommendations. CONCLUSIONS: Based on the evidence available for each element of perioperative care pathways, the Enhanced Recovery After Surgery (ERAS®) Society presents a comprehensive consensus review, clinical considerations and recommendations for anaesthesia care in patients undergoing gastrointestinal surgery within an ERAS programme. This unified protocol facilitates involvement of anaesthesiologists in the implementation of the ERAS programmes and allows for comparison between centres and it eventually might facilitate the design of multi-institutional prospective and adequately powered randomized trials.


Subject(s)
Anesthesia , Consensus , Digestive System Surgical Procedures , Acute Kidney Injury/etiology , Digestive System Surgical Procedures/adverse effects , Humans , Intraoperative Complications/prevention & control , Monitoring, Physiologic , Postoperative Nausea and Vomiting/prevention & control , Recovery of Function
3.
Br J Surg ; 102(6): 577-89, 2015 May.
Article in English | MEDLINE | ID: mdl-25759947

ABSTRACT

BACKGROUND: Intraoperative goal-directed therapy (GDT) was introduced to titrate intravenous fluids, with or without inotropic drugs, based on objective measures of hypovolaemia and cardiac output measurements to improve organ perfusion. This meta-analysis aimed to determine the effect of GDT on the recovery of bowel function after abdominal surgery. METHODS: MEDLINE, Embase, the Cochrane Library and PubMed databases were searched for randomized clinical trials and cohort studies, from January 1989 to June 2013, that compared patients who did, or did not, receive intraoperative GDT, and reported outcomes on the recovery of bowel function. Time to first flatus and first bowel motion, time to tolerate oral diet, postoperative nausea and vomiting, and primary postoperative ileus were included. RESULTS: Thirteen trials with 1399 patients were included in the analysis. GDT shortened the time to the first bowel motion (weighted mean difference (WMD -0·67, 95 per cent c.i. -1·23 to -0·11; P = 0·020) and time to tolerate oral intake (WMD -0·95, -1·81 to -0·10; P = 0·030), and reduced postoperative nausea and vomiting (risk difference -0·15, -0·26 to -0·03; P = 0·010). When only high-quality studies were included, GDT reduced only the time to tolerate oral intake (WMD -1·18, -2·03 to -0·33; P = 0·006). GDT was more effective outside enhanced recovery programmes and in patients undergoing colorectal surgery. CONCLUSION: GDT facilitated the recovery of bowel function, particularly in patients not treated within enhanced recovery programmes and in those undergoing colorectal operations.


Subject(s)
Digestive System Surgical Procedures , Fluid Therapy/methods , Gastrointestinal Diseases/surgery , Gastrointestinal Motility/physiology , Goals , Intestines/physiopathology , Postoperative Complications/prevention & control , Humans , Intraoperative Period
4.
Acta Anaesthesiol Scand ; 59(10): 1212-31, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26346577

ABSTRACT

BACKGROUND: The present article has been written to convey concepts of anaesthetic care within the context of an Enhanced Recovery After Surgery (ERAS) programme, thus aligning the practice of anaesthesia with the care delivered by the surgical team before, during and after surgery. METHODS: The physiological principles supporting the implementation of the ERAS programmes in patients undergoing major abdominal procedures are reviewed using an updated literature search and discussed by a multidisciplinary group composed of anaesthesiologists and surgeons with the aim to improve perioperative care. RESULTS: The pathophysiology of some key perioperative elements disturbing the homoeostatic mechanisms such as insulin resistance, ileus and pain is here discussed. CONCLUSIONS: Evidence-based strategies aimed at controlling the disruption of homoeostasis need to be evaluated in the context of ERAS programmes. Anaesthesiologists could, therefore, play a crucial role in facilitating the recovery process.


Subject(s)
Digestive System Surgical Procedures , Perioperative Care , Postoperative Care , Recovery of Function , Anesthesia, Epidural , Anesthesiology , Cognition Disorders/etiology , Homeostasis , Humans , Insulin Resistance , Pain, Postoperative/prevention & control , Physician's Role , Stress, Physiological , Water-Electrolyte Balance
5.
Eur Rev Med Pharmacol Sci ; 28(7): 2827-2836, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38639522

ABSTRACT

OBJECTIVE: The study aimed to evaluate the utility and safety of ancillary maneuvers during oocyte retrieval for patients with endometrioma that makes ovum pick-up hard due to poor ovarian surgical accessibility. PATIENTS AND METHODS: Cases of 251 women with ovarian endometriomas undergoing in vitro fertilization (IVF) in our infertility unit were retrospectively analyzed to evaluate the clinical IVF cycle outcomes after oocyte retrieval. Controls (n = 251) were age-matched women without endometriomas who underwent an uncomplicated oocyte retrieval. RESULTS: No statistically significant differences were observed between groups except for the number of oocytes retrieved, which was higher in the control group than in the group of women with endometrioma. On the contrary, there were no differences between the experimental groups in the fertilization rate and number of embryos, and neither were there in the pregnancy and live birth rate. Moreover, the surgical complications were infrequent and similar between the two analyzed groups. Accidental or voluntary endometrioma punctures were not accompanied by increases in the risk of a pelvic infection. CONCLUSIONS: In conclusion, patients with endometrioma can undergo high-performance oocyte recovery procedures thanks to safe accessory maneuvers during the ovum pick-up.


Subject(s)
Endometriosis , Infertility , Pregnancy , Humans , Female , Endometriosis/surgery , Endometriosis/complications , Retrospective Studies , Oocyte Retrieval , Fertilization in Vitro , Pregnancy Rate
6.
Surg Endosc ; 27(12): 4711-20, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23955727

ABSTRACT

BACKGROUND: Postoperative urinary retention (POUR) is a common complication of ambulatory inguinal herniorraphy, with an incidence reaching 38%, and many surgeons require patients to void before discharge. This study aimed to assess whether the implementation of a bladder scan-based voiding protocol reduces the time until discharge after ambulatory inguinal herniorraphy without increasing the rate of POUR. METHODS: As part of a perioperative care pathway, a protocol was implemented to standardize decision making after elective inguinal hernia repair (February 2012). Patients were assessed with a bladder scan, and those with <600 mL of urine were discharged home, whereas those with more than 600 mL of urine had an in-and-out catheterization before discharge. The patients received written information about urinary symptoms and instructions to present to the emergency department if they were unable to void at home. An audit of scheduled outpatient inguinal hernia repairs between October 2011 and July 2012 was performed. Comparisons were made using the t test, Fisher's exact test, and Wilcoxon rank sum test where appropriate. Statistical significance was defined a priori as a p value lower than 0.05. RESULTS: During the study period, 124 patients underwent hernia repair: 60 before and 64 after implementation of the protocol. The findings showed no significant differences in patient characteristics, laparoscopic approach (35 vs. 33%; p = 0.80), proportion receiving general anesthesia (70 vs. 73%; p = 0.67), or amount of intravenous fluids given (793 vs. 663 mL; p = 0.07). The proportion of patients voiding before discharge was higher after protocol implementation (73 vs. 89%; p = 0.02). The protocol had no impact on median time to discharge (190 vs. 205 min; p = 0.60). Only one patient in each group presented to the emergency department with POUR (2%). CONCLUSION: After ambulatory inguinal herniorraphy, implementation of a bladder scan-based voiding protocol did not result in earlier discharge. The incidence of POUR was lower than reported in the literature.


Subject(s)
Ambulatory Surgical Procedures , Hernia, Inguinal/surgery , Herniorrhaphy/adverse effects , Patient Discharge/trends , Urinary Bladder/diagnostic imaging , Urinary Catheterization/methods , Urinary Retention/diagnosis , Female , Follow-Up Studies , Herniorrhaphy/methods , Humans , Incidence , Male , Middle Aged , Perioperative Care/methods , Postoperative Complications , Quebec/epidemiology , Retrospective Studies , Ultrasonography , Urinary Bladder/pathology , Urinary Retention/epidemiology , Urinary Retention/etiology
7.
Front Radiol ; 3: 1336902, 2023.
Article in English | MEDLINE | ID: mdl-38304344

ABSTRACT

Challenging tasks such as lesion segmentation, classification, and analysis for the assessment of disease progression can be automatically achieved using deep learning (DL)-based algorithms. DL techniques such as 3D convolutional neural networks are trained using heterogeneous volumetric imaging data such as MRI, CT, and PET, among others. However, DL-based methods are usually only applicable in the presence of the desired number of inputs. In the absence of one of the required inputs, the method cannot be used. By implementing a generative adversarial network (GAN), we aim to apply multi-label automatic segmentation of brain tumors to synthetic images when not all inputs are present. The implemented GAN is based on the Pix2Pix architecture and has been extended to a 3D framework named Pix2PixNIfTI. For this study, 1,251 patients of the BraTS2021 dataset comprising sequences such as T1w, T2w, T1CE, and FLAIR images equipped with respective multi-label segmentation were used. This dataset was used for training the Pix2PixNIfTI model for generating synthetic MRI images of all the image contrasts. The segmentation model, namely DeepMedic, was trained in a five-fold cross-validation manner for brain tumor segmentation and tested using the original inputs as the gold standard. The inference of trained segmentation models was later applied to synthetic images replacing missing input, in combination with other original images to identify the efficacy of generated images in achieving multi-class segmentation. For the multi-class segmentation using synthetic data or lesser inputs, the dice scores were observed to be significantly reduced but remained similar in range for the whole tumor when compared with evaluated original image segmentation (e.g. mean dice of synthetic T2w prediction NC, 0.74 ± 0.30; ED, 0.81 ± 0.15; CET, 0.84 ± 0.21; WT, 0.90 ± 0.08). A standard paired t-tests with multiple comparison correction were performed to assess the difference between all regions (p < 0.05). The study concludes that the use of Pix2PixNIfTI allows us to segment brain tumors when one input image is missing.

8.
Eur Rev Med Pharmacol Sci ; 27(5): 2018-2026, 2023 03.
Article in English | MEDLINE | ID: mdl-36930501

ABSTRACT

OBJECTIVE: Frozen-thawed embryo transfer (FET) cycles require the use of luteal phase support (LPS) for supporting implantation, endometrial and embryo maturity. Individualized LPS should be chosen according to the used endometrial preparation protocol. The aim of the study was to analyze the effectiveness of two different vaginal Progesterone doses for women who underwent FET cycle and the same endometrial preparation without using the GnRh analogue. PATIENTS AND METHODS: 607 women who underwent FET cycle were included in the study. 305 patients received luteal support with 600 mg/day vaginal Progesterone and 302 patients were treated with 800 mg/day of vaginal Progesterone. RESULTS: In the 800 mg/day group, the mean serum Progesterone concentration on the day of embryo transfer was higher than in the 600 mg group (14.00±6.18 ng/mL and 12.22±5.39, respectively, p < 0.001). Moreover, human chorionic gonadotrophin (hCG) positive and ongoing pregnancy rates were higher in the group of patients who received LPS with 800 mg/day of Progesterone than in the group of patients treated with 600 mg/day of Progesterone.  CONCLUSIONS: In patients undergoing FET cycles following endometrial preparation made without previously using the GnRh analogue, 800 mg doses of vaginal Progesterone as LPS improve reproductive outcomes.


Subject(s)
Lipopolysaccharides , Progesterone , Pregnancy , Female , Humans , Pregnancy Rate , Embryo Transfer/methods , Gonadotropin-Releasing Hormone , Luteal Phase
9.
J Clin Med ; 12(4)2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36835958

ABSTRACT

The aim of the study was to investigate whether the COVID-19 pandemic and related measures had an influence on colorectal cancer (CRC) presentation, management, and outcomes; it was a retrospective monocentric study. CRC patients undergoing surgery during the COVID-19 pandemic (1 March 2020-28 February 2022) (group B) were compared with patients operated on in the previous two years (1 March 2018-29 February 2020) in the same unit (group A). The primary outcome was to investigate whether there were differences in concern regarding the stage at presentation, as a whole and after dividing groups based on cancer location (right colon cancer, left colon cancer, rectal cancer). Secondary outcomes included differences in the number of patients admitted from emergency departments and emergency surgeries between periods, and differences in the postoperative outcomes. A subanalysis within the pandemic group was conducted on the same outcomes, dividing the aforementioned group based on pandemic trends. Two hundred and eighty (280) were operated on during the study period: 147 in group A and 133 in group B. Stage at presentation was similar between groups; however, the subgroups analysis showed that in the pandemic group, the number of early-stage left colon cancer occurrences almost halves, yet not significantly. Emergency department referral was more common in group B (p-value: 0.003); in group B, they also had longer operations and there was a more frequent use of ostomy. No differences in the number of postoperative complications nor in the postoperative outcomes were found. Patients with CRC were more frequently referred through the emergency department during the COVID-19 pandemic and left-sided cancers appear to be generally diagnosed at a more advanced stage. Postoperative outcomes showed that high specialized colorectal units can deliver standard high-level treatment under high-pressure external conditions.

10.
Eur Rev Med Pharmacol Sci ; 27(13): 6384-6392, 2023 07.
Article in English | MEDLINE | ID: mdl-37458655

ABSTRACT

OBJECTIVE: Obesity is one of the main concerns for public health and is becoming an increasingly widespread problem worldwide. Women are more likely to require a cesarean section and have a longer hospital stay after delivery. Excess body weight can interfere with ovulation and make it more difficult for embryos to implant in the uterus. A high body mass index (BMI) has controversial effects on the outcomes of medically assisted reproduction treatments (IVF) and, if careful counseling is not performed, medical-legal risks may be incurred. While some researchers argue that obesity does not particularly affect ART outcomes, other studies claim that a high BMI does not interfere with embryonic development. Both the American Society for Reproductive Medicine (ASRM) and the European Society of Human Reproduction and Embryology (ESHRE) has stated that there is no clear evidence supporting a BMI limit for IVF treatment and that each patient should be evaluated on an individual basis. The purpose of our study was to evaluate whether performing in vitro fertilization on these patients increases the risk of medical, surgical, and anesthetic complications of oocyte retrieval. PATIENTS AND METHODS: From January 2011 to December 2022, all patients with BMI higher than 25 were enrolled in the study (n=766). Complications and risks related to oocyte retrieval were evaluated, and patients were divided according to BMI groups. RESULTS: With the one-way ANOVA test, all groups were compared with the control group, and none showed statistically significant differences, only the number of produced embryos in the BMI group between 30-34.9 was lower and statistically significant. CONCLUSIONS: Only one study has analyzed these aspects, mainly focusing on the need for anesthesia drugs and any related complications, and the same author reported greater difficulty in performing oocyte retrieval. The same study recorded an increase in incomplete oocyte retrievals. Our work does not confirm any of these impressions.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Oocyte Retrieval , Humans , Pregnancy , Female , Oocyte Retrieval/adverse effects , Reproductive Techniques, Assisted/adverse effects , Cesarean Section , Obesity/complications , Fertilization in Vitro/adverse effects , Pregnancy Rate , Retrospective Studies
11.
Br J Anaesth ; 108(5): 850-6, 2012 May.
Article in English | MEDLINE | ID: mdl-22408272

ABSTRACT

BACKGROUND: This study was undertaken to determine the impact of an intrathecal mixture of bupivacaine and morphine, when compared with systemic morphine, on the quality of postoperative analgesia and other outcomes in the context of the enhanced recovery after surgery (ERAS) programme for laparoscopic colonic resection. METHODS: Fifty patients undergoing general anaesthesia were randomly allocated to receive either a spinal mixture of bupivacaine and morphine followed by oral oxycodone (spinal group) or patient-controlled analgesia (PCA group). The primary outcome was consumption of opioids during the first three postoperative days. Secondary outcomes were pain scores, return of bowel function and dietary intake, readiness to hospital discharge, and length of hospital stay. RESULTS: Postoperative opioid consumption in the spinal group was significantly less over the first three postoperative days (P<0.001). The quality of analgesia at rest in the first 24 h was better in the spinal group (P<0.005). Excessive sedation and respiratory depression were reported in two elderly patients with spinal analgesia. There were no differences between the two groups in other outcomes (return of bowel function and dietary intake, readiness to hospital discharge, and length of hospital stay). CONCLUSIONS: When ERAS programme is used for laparoscopic colonic resection, an intrathecal mixture of bupivacaine and morphine was associated with less postoperative opioid consumption, but has no other advantages over systemic opioids.


Subject(s)
Anesthesia, Spinal/methods , Colectomy/methods , Pain, Postoperative/prevention & control , Adult , Aged , Aged, 80 and over , Analgesia, Patient-Controlled/methods , Analgesics, Opioid/administration & dosage , Anesthesia Recovery Period , Anesthesia, General , Anesthetics, Local/administration & dosage , Bupivacaine/administration & dosage , Colectomy/adverse effects , Drug Administration Schedule , Drug Combinations , Female , Humans , Laparoscopy/adverse effects , Laparoscopy/methods , Length of Stay/statistics & numerical data , Male , Middle Aged , Morphine/administration & dosage , Pain Measurement/methods , Postoperative Care/methods , Postoperative Complications
12.
Eur Rev Med Pharmacol Sci ; 26(9): 3282-3288, 2022 05.
Article in English | MEDLINE | ID: mdl-35587080

ABSTRACT

OBJECTIVE: This study compares the miscarriage rate of pregnancies after trans-myometrial eggs retrieval to transvaginal eggs retrieval. PATIENTS AND METHODS: In the period between January 2004 and December 2020, 13,323 egg retrievals were carried out. In 699 cases, the ovaries were unreachable. Alternative maneuvers were performed to solve this problem, but despite this, in 132 patients the technique of trans-myometrial sampling had to be used. 26 patients were excluded from the study, because of the inclusion criteria, and therefore two groups of 106 patients were selected, Group A and Group B (control). RESULTS: In the comparison between the two groups, there were no statistically significant differences in abortion rates, pregnancy rates and complications after the technique. CONCLUSIONS: This study shows that the abortion rate in trans-myometrial oocyte retrieval does not change when compared to classic retrieval, despite the sampling needle completely crossing the myometrium. Furthermore, the pregnancy rate and the complication rate do not appear to have worsened with this technique.


Subject(s)
Abortion, Induced , Abortion, Spontaneous , Female , Humans , Myometrium , Pregnancy , Pregnancy Rate
13.
Eur Rev Med Pharmacol Sci ; 26(15): 5520-5528, 2022 08.
Article in English | MEDLINE | ID: mdl-35993649

ABSTRACT

OBJECTIVE: The study aimed to demonstrate that the risk of Cesarean Scar Pregnancy (CSP) for patients with isthmocele decreases when the embryo transfer is performed on day 5 at the blastocyst stage. PATIENTS AND METHODS: From January 2014 to December 2021, 167 patients who previously had an IVF treatment and delivered by cesarean section, were selected. The isthmocele was found in 98 of them. Firstly, we evaluated whether the isthmocele increases the risk of CSP. Subsequently, we investigated the possible correlation between the risk of the CSP with the day of the embryo transfer. Hence, the selected patients were divided into two groups: Group A where the embryo transfer was performed at the cleavage stage on day 3 and Group B where the embryo was transferred at the blastocyst stage on day 5. RESULTS: The outcomes show that the isthmocele does not seem to increase the risk of CSP, while the embryo transfer on day 3 increases its rate. CONCLUSIONS: When the isthmocele is diagnosed, according to our results, an embryo transfer on day 5 at the blastocyst stage seems to minimize the risk of the CSP.


Subject(s)
Cicatrix , Pregnancy, Ectopic , Case-Control Studies , Cesarean Section/adverse effects , Cicatrix/diagnostic imaging , Cicatrix/pathology , Female , Fertilization in Vitro/adverse effects , Fertilization in Vitro/methods , Humans , Pregnancy , Pregnancy, Ectopic/diagnostic imaging , Pregnancy, Ectopic/etiology , Retrospective Studies , Ultrasonography, Interventional
14.
Eur Rev Med Pharmacol Sci ; 25(15): 4964-4972, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34355368

ABSTRACT

OBJECTIVE: Vitamin D (VitD) is a secosteroid hormone showing both antiproliferative and immunomodulatory effects. Its involvement in placental steroidogenesis and endometrial decidualization even plays a role in other gynecological functions, including assisted reproductive technology (ART). However, controversial data have been reported on its implication in pregnancy outcomes during In Vitro Fertilization (IVF) programs. In order to elucidate the VitD role in ART success, we evaluated serum and follicular fluid (FF) VitD levels in infertile women concerning the pregnancy rate. PATIENTS AND METHODS: In our IVF center, 446 patients, under the age of 42 years old,  were evaluated in the period between January 2018 and December 2019. It is here important to clarify that, in order to respect the exclusion criteria, only 103 of them were enrolled for the study concerning the VitD evaluation in serum and follicular fluid at the time of the egg retrieval. This took place both in 34 pregnant patients (Group 1) and 69 non-pregnant ones (Group 2). Furthermore, the collection of these data gave us the opportunity to assess a possible correlation between the VitD levels and the achievement of pregnancy in the performed IVF cycles. RESULTS: The studied group included 103 eligible women. The average age for Group 1 was 33.12 ± 3.72 yrs whereas 33.72+3.99 yrs (p=0.467) for Group 2. The main differences were observed concerning follicle numbers of 17-21 mm (p=0.0043), the number of retrieved oocytes (p=0.0207), as well as the number of mature oocytes (p=0.0233) among the different groups. Different reference ranges, established according to the pregnancy outcomes, revealed that pregnant women with >36 yrs showed significantly higher levels of VitD. CONCLUSIONS: Increased serum and FF-VitD levels in women undergoing IVF with age ≥36 yrs, were significantly associated with a favorable outcome to achieve and carry on with the pregnancy.


Subject(s)
Infertility, Female/metabolism , Vitamin D/metabolism , Adult , Biological Availability , Cross-Sectional Studies , Female , Humans , Pregnancy , Pregnancy Outcome , Vitamin D/blood
17.
J Cell Biol ; 140(2): 305-13, 1998 Jan 26.
Article in English | MEDLINE | ID: mdl-9442106

ABSTRACT

Rab proteins are small molecular weight GTPases that control vesicular traffic in eucaryotic cells. A subset of Rab proteins, the Rab3 proteins are thought to play an important role in regulated exocytosis of vesicles. In transfected AtT-20 cells expressing wild-type Rab3D, we find that a fraction of the protein is associated with dense core granules. In the same cells, expression of a mutated isoform of Rab3D, Rab3D N135I, inhibits positioning of dense core granules near the plasma membrane, blocks regulated secretion of mature ACTH, and impairs association of Rab3A to membranes. Expression of Rab3D N135I does not change the levels of ACTH precursor or the efficiency with which the precursor is processed into ACTH hormone and packaged into dense core granules. We also find that cells expressing mutated Rab3D differentiate to the same extent as untransfected AtT-20 cells. We conclude that expression of Rab3D N135I specifically impairs late membrane trafficking events necessary for ACTH hormone secretion.


Subject(s)
GTP-Binding Proteins/genetics , Nerve Tissue Proteins/genetics , Proto-Oncogene Proteins/genetics , Adrenocorticotropic Hormone/analysis , Animals , Cell Compartmentation , Cells, Cultured , Fluorescent Antibody Technique, Indirect , GTP-Binding Proteins/metabolism , Microscopy, Immunoelectron , Nerve Tissue Proteins/metabolism , Proto-Oncogene Proteins/metabolism , Rabbits , rab3 GTP-Binding Proteins
18.
J Cell Biol ; 127(5): 1233-43, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7962086

ABSTRACT

Caveolae, also termed plasmalemmal vesicles, are small, flask-shaped, non-clathrin-coated invaginations of the plasma membrane. Caveolin is a principal component of the filaments that make up the striated coat of caveolae. Using caveolin as a marker protein for the organelle, we found that adipose tissue is the single most abundant source of caveolae identified thus far. Caveolin mRNA and protein are strongly induced during differentiation of 3T3-L1 fibroblasts to adipocytes; during adipogenesis there is also a dramatic increase in the complexity of the protein composition of caveolin-rich membrane domains. About 10-15% of the insulin-responsive glucose transporter GLUT4 is found in this caveolin-rich fraction, and immuno-isolated vesicles containing GLUT4 also contain caveolin. However, in non-stimulated adipocytes the majority of caveolin fractionates with the plasma membrane, while most GLUT4 associates with low-density microsomes. Upon addition of insulin to 3T3-L1 adipocytes, there is a significant increase in the amount of GLUT4 associated with caveolin-rich membrane domains, an increase in the amount of caveolin associated with the plasma membrane, and a decrease in the amount of caveolin associated with low-density microsomes. Caveolin does not undergo a change in phosphorylation upon stimulation of 3T3-L1 adipocytes with insulin. However, after treatment with insulin it is associated with a 32-kD phosphorylated protein. Caveolae thus may play an important role in the vesicular transport of GLUT4 to or from the plasma membrane. 3T3-L1 adipocytes offer an attractive system to study the function of caveolae in several cellular trafficking and signaling events.


Subject(s)
Adipocytes/cytology , Caveolins , Cell Membrane/metabolism , Membrane Proteins/metabolism , Monosaccharide Transport Proteins/metabolism , Muscle Proteins , 3T3 Cells , Adipocytes/metabolism , Adipocytes/ultrastructure , Adipose Tissue/chemistry , Animals , Biological Transport , Caveolin 1 , Cell Differentiation , Cell Membrane/ultrastructure , Endocytosis , Glucose Transporter Type 4 , Insulin/pharmacology , Membrane Proteins/analysis , Membrane Proteins/biosynthesis , Membrane Proteins/genetics , Mice , Microscopy, Electron , Phosphoproteins/metabolism , Phosphorylation , RNA, Messenger/genetics , RNA, Messenger/metabolism
19.
J Cell Biol ; 133(2): 257-68, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8609160

ABSTRACT

We have identified and characterized Cab45, a novel 45-kD protein from mouse 3T3-L1 adipocytes. Cab45 is ubiquitously expressed, contains an NH2-terminal signal sequence but no membrane-anchor sequences, and binds Ca2+ due to the presence of six EF-hand motifs. Within the superfamily of calcium-binding proteins, it belongs to a recently identified group of proteins consisting of Reticulocalbin (Ozawa, M., and T. Muramatsu. 1993. J. Biol. Chem. 268:699-705) and ERC 55 (Weis, K., G. Griffiths, and A.I. Lamond. 1994. J. Biol Chem. 269:19142-19150), both of which share significant sequence homology with Cab45 outside the EF-hand motifs. In contrast to reticulocalbin and ERC-55 which are soluble components of the endoplasmic reticulum, Cab45 is a soluble protein localized to the Golgi. Cab45 is the first calcium-binding protein localized to the lumenal portion of a post-ER compartment; Cab45 is also the first known soluble protein resident in the Golgi lumen. Cab45 can serve as a model protein to determine the mechanism of retention of soluble proteins in the Golgi compartment.


Subject(s)
Calcium-Binding Proteins/analysis , Glycoproteins/analysis , Golgi Apparatus/chemistry , 3T3 Cells , Adipocytes , Amino Acid Sequence , Animals , Base Sequence , Brefeldin A , Calcium-Binding Proteins/chemistry , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/metabolism , Cloning, Molecular , Cyclopentanes/pharmacology , DNA, Complementary/genetics , Gene Expression , Glycoproteins/chemistry , Glycoproteins/genetics , Glycoproteins/metabolism , Glycosylation , Mice , Molecular Sequence Data , Molecular Weight , Protein Synthesis Inhibitors/pharmacology , RNA, Messenger/analysis , Recombinant Fusion Proteins/metabolism , Sequence Analysis, DNA
20.
J Phys Chem B ; 112(29): 8806-14, 2008 Jul 24.
Article in English | MEDLINE | ID: mdl-18582099

ABSTRACT

GFP mutants are known to display fluorescence flickering, a process that occurs in a wide time range. Because serine 65, threonine 203, glutamate 222, and histidine 148 have been indicated as key residues in determining the GFP fluorescence photodynamics, we have focused here on the role of histidine 148 and glutamate 222 by studying the fluorescence dynamics of GFPmut2 (S65A, V68L, and S72A GFP) and its H148G (Mut2G) and E222Q (Mut2Q) mutants. Two relaxation components are found in the fluorescence autocorrelation functions of GFPmut2: a 10-100 micros pH-dependent component and a 100-500 micros laser-power-dependent component. The comparison of these three mutants shows that the mutation of histidine 148 to glycine induces a 3-fold increase in the protonation rate, thereby indicating that the protonation-deprotonation of the chromophore occurs via a proton exchange with the solution mediated by the histidine 148 residue. The power-dependent but pH-independent relaxation mode, which is not affected by the E222Q and H148G mutations, is due to an excited-state process that is probably related to conformational rearrangements of the chromophore after the photoexcitation, more than to the chromophore excited-state proton transfer.


Subject(s)
Green Fluorescent Proteins/chemistry , Luminescent Agents/chemistry , Photons , Protons , Computer Simulation , Glutamic Acid/chemistry , Histidine/chemistry , Hydrogen-Ion Concentration , Mutation , Protein Conformation , Serine/chemistry , Spectrometry, Fluorescence , Threonine/chemistry
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