By W. Larson. Georgia Institute of Technology. 2018.
Several studies have demonstrated that a tion risk groups have been identified for stage I endo- laparoscopic approach does not compromise the metrial cancer prognosis of patients with endometrial cancer discount 20 mg prednisone amex, with Low risk: stage IA prednisone 10 mg for sale, grade 1 and 2, endometrioid adeno- probably a more rapid recovery period and less carcinoma postoperative complications, which is, considering the profile of these patients, a distinct advantage. A Intermediate risk: number a limiting factors such as obesity and an en- 1. Stage I: • moderate to poorly differentiated tumor (grade 3) larged uterus may be contraindications for laparo- • presence of lympho-vascular invasion scopic surgery. A laparoscopic approach requires • outer third myometrial invasion (stage IB) special training and skills. Age ≥50 years with any two risk factors listed above; or is longer compared to an open approach and it is 3. Age ≥70 with any risk factor listed above still shown to be the more expensive procedure. Histological evaluation of specimens is manda- High risk: stage IB plus grade 3, non-endometrioid histology tory to determine possible adjuvant treatment. The histopathologist should report on grade or differen- tiation, size of the tumor, depth of myometrium invasion, lymph–vascular space invasion, cervical Table 5 Overview of treatment in stage I endometrial involvement and adnexal involvement. Although 7 cancer risk according to groups in Table 4 in the latest 2009 FIGO staging classification posi- tive washings do not change the stage, the presence Risk group Adjuvant treatment of malignant cells in the pouch of Douglas washing Low risk No adjuvant treatment should be reported (Table 4). Intermediate risk Brachytherapy • With 2 high-risk factors Adjuvant treatment (age >50 years) • With 1 risk factor (age Although in many low-resource countries, radio- >70 years) therapy is not easily available, it may be considered High risk External beam radio- for certain high-risk patients. The adjuvant treat- therapy and brachytherapy ment should be individually tailored. Low-risk 362 Cancer of the Uterine Corpus Risk factors for recurrent disease in stage I endo- including cancer, hypertension and diabetes. In metrial cancer include grade 3 tumors with infiltra- transitional but increasingly also in low-resource tion into the outer half of the myometrium. These settings a large proportion of society tend to be patients are certainly at risk for positive pelvic and obese. Communities need to be sensitized about or para-aortic lymph nodes. If the lymph node this link and the dangers associated with metabolic status is known and positive the patients should re- syndrome. Secondly, endometrial cancer has its ceive full pelvic radiation maybe including the peak incidence in postmenopausal women. As a consequence it tive pelvic and para-aortic lymph nodes can be is not sufficient to sensitize men and women about adequately treated with vaginal brachytherapy6. It is more frequently recognized that repro- EBRT is recommended. The role of systemic treat- ductive healthcare should be provided along a con- ment, i. In patients with a non-endometrioid cancer such as UTERINE SARCOMAS uterine serous papillary carcinoma and clear cell Uterine sarcomas represent only 3–8% of all uter- carcinomas it has become common practice to give ine malignancies. The low occurrence precludes intravenous chemotherapy including carbo- any prospective studies and most published data platinum and paclitaxel (see Chapter 28). A number concern retrospective studies and case histories. We nosarcoma (previously known as malignant mixed have to wait for further studies. Müllerian tumors or MMMT) are now seen as poorly differentiated epithelial carcinomas. In this Recurrence of endometrial cancer chapter, carcinosarcoma is discussed together with In a limited number of patients the disease will re- the uterine sarcomas. When the recurrence is local (vagina or vagina top) surgery by an experienced doctor or radio- Carcinosarcoma therapy can still cure the patient. In cases of distant These tumors represent <5% of all uterine cancers. A polypoid tumor on macroscopic positive progesterone receptors (medroxyproges- examination is shown in Figure 7. Palliative These are biphasic neoplasms involving malig- care is described in Chapter 32.
Pigs harbor H1 and H3 buy 20 mg prednisone fast delivery, whereas horses have H3 and H7 cheap prednisone 40 mg visa. Other mammals and nonaquatic birds occasionally become infected, but do not appear to maintain stable lineages over time. Inﬂuenza HA and NA molecules mediate viral attachment and entry to host cells and release of progeny viral particles by budding through themembrane of infected cells (Lamb and Krug 2001). Current under- standing assigns adsorption and entry functions to HA (Steinhauer and Wharton 1998) and release of progeny to NA (Colman 1998). However, the HA and NA molecules may have multiple active sites and various functions, and the diﬀerent subtypes of each molecule diﬀer signiﬁ- cantly (Lamb and Krug 2001). With those caveats, a brief summary of structure and function follows. The HA mole- cule then cleaves into two parts, the terminal HA1 and the basal HA2 fragments. Cleavage exposes on the surface of HA2 a highly conserved, hydrophobic region that mediates fusion and entry via the host mem- brane (Wilson and Cox 1990; Skehel and Wiley 2000). EXPERIMENTAL EVOLUTION: INFLUENZA 209 B Receptor binding site 155 193 188 A 133 186 126 220 144 145146 226 217 D 143 205 122 208 78 E 83 54 275 53 C 278 Figure 13. This drawing is based on structural analysis of H3 hemagglutinin. Inference about other HA subtypes depends on presumed structural similarity with H3. Labeled amino acid num- bers for HA1 are a subset of the variable sites listed in Wiley et al. The sialic acid binding site oc- curs near the tip of HA1. The letters A–E locate the major regions for 210 CHAPTER 13 Tyr 195 Leu 194 Glu 190 Thr 155 His 183 HO N OH N H H O N HO 9 OH Trp 153 7 CH 8 3 O 5 NH OH 6 OH H RO 3 4 O 2 O O O Leu 226 135 O HO 225 Ser 136 224 H Tyr 98 N 137 138 98 Y→F 5 183 H→F 12 225 G→D 53 136 S →A 30 183 H→A — 225 G→R 136 136 S →T 45 190 E →A 125 226 L →P 42 153 W→A — 194 L →A 3 228 S →G 112 153 W→F 39 195 Y→F 36 Figure 13. The listing below shows the binding aﬃnities for sialic acid when particular amino acids are changed ex- perimentally by site-directed mutagenesis (Martín et al. The number on the left deﬁnes the amino acid site in HA1, x → y shows the original and new amino acid, and the number on the right is the binding aﬃnity of the mutant as a percentageof the aﬃnity of the wild type. Dashesshow cases in which the recep- torsiteisnot properly expressed. Redrawn from Skehel and Wiley (2000), with permission from the Annual Review of Biochemistry, www. The sialic acid has been displaced slightly to show the structure of the ﬁt. The amino acids numbered within and around the binding site provide a reference for the location of important residues. The bottom of the ﬁgure shows the eﬀect on binding aﬃnity to sialic acid caused by experimental change of particular amino acids. This space-ﬁlling model has roughly the same orientation as the schematic diagram in ﬁgure 13. Antibodies bound to HA can neutralizeinﬂuenza infectivity by physi- cally obstructing the sialic acid binding site. For example, the HC19 MAb binds to HA of strain X-31 (H3 subtype),partially overlapping the sialic acid binding site (Bizebard et al. The speciﬁc antibody-epitope re- gion of direct contact covers 1250 Å2,including amino acids 134, 136, 212 CHAPTER 13 153, 155, and 194. The de- pression extends 315 Å2,ofwhichtheantibody binding region covers 167 Å2. Antibody escape mutants map to the ridge of amino acids that ring the conserved amino acids in the binding pocket. Each upper arm forms an Fab frag- ment, with the binding region on the tip of the fragment. An antibody molecule can be cleaved to release two identical Fab fragments, each containing a binding region. However, other antibody escape mutants map to regions of HA away from the sialic acid binding site. Those sites are too far away to allow overlap of the direct antibody- epitope binding region with the sialic acid binding site. The Fab fragment of HC45 bound to its epitope with approximately the same kinetics as HC19 bound to its epitope, but HC19 was an order of mag- nitude more eﬃcient at neutralization.
In a globalised world – whether we like it or not – we live in an environment of multiple languages generic 5mg prednisone. Modern times are polyglot times safe prednisone 10mg, and ‘monoglot’ individuals begin to realise that speaking just one language has its disadvantages. They start asking themselves how long it takes to learn another language and if languages are within the reach of everybody. Typically, they also want to know how to choose good teachers and how to avoid bad teachers. The subtitle of the present guide, Fast Language Learning, may be subject to misunderstanding. If that’s the way you dream about approaching your next language, stop reading here. There is nothing snug and cosy about The Word Brain. On the contrary, this short guide for adults may appear harsh and rude, and demands your determination, Print: Amazon. The place where you will be told to learn your next language could be the second surprise. Usually, adults think of language learning in terms of people interacting with each other, either in a beautiful city or a romantic countryside, in situations ranging from gentle and friendly meetings to tantra-inspired gatherings. Again, you will find nothing of all this in The Word Brain. When we later summarise how to rapidly achieve reading and comprehension skills, I will prescribe you months of lonely learning sessions with books and audio files. If you don’t like the idea that fast language learning is essentially a lonely battle, goodbye. While I set the goals and define the time frame, it is up to you to find the most promising road to achieve your goals and to develop the skills needed for an effort that is going to last months and sometimes years. You will partly invent yourself as your own teacher. If you feel scared about this perspective, consider at least reading the first chapter, Words. After that, you may decide that you have no time to learn a new language, but never again will you say that you have no talent for it. This revelation might well be worth half an hour of reading. Then let me briefly explain how The Word Brain came to life. It all started when, on one of those birthdays that are turning points in life, I offered myself an exclusive present most of my busy colleagues can rarely afford: time. I would dedicate two consecutive years to learning th my 7 language. Just to complicate matters, I accepted a triple challenge: Web: TheWordBrain. Learn a language at an advanced age – at 50, the memory is not what it used to be at 20. Learn a language without teachers, using only books, CDs and TV. After working at the University Hospitals in Bonn and Frankfurt, I published and edited a small number of books (www. Aside from medicine, I have always cherished a second passion: the acquisition of other people’s languages. I was fascinated to observe how new languages gradually entered my brain; to struggle with learning and forgetting; to feel the brain becoming saturated, craving for a break; and to discover how learning sometimes makes true ‘quantum leaps’, when sketchy pieces of knowledge suddenly coalesce into an almost-fluent understanding. Sensing the dense fog of incomprehension that lifts over a landscape you have never seen before is an exhilarating experience. My passion started at school where the languages I was taught – French, English, and Latin – had long-lasting consequences on my life.
SDF-1 (stromal cell-derived factor 1) was identified as the natural ligand of CXCR4 and is able to inhibit the entry of T-tropic HIV-1 isolates into activated CD4 T cells buy generic prednisone 10mg on-line. T-tropic HIV-1 isolates mainly infect activated peripheral blood CD4 T cells and cell lines and use CXCR4 for entry into the CD4-positive target cell order 10 mg prednisone overnight delivery. M-tropic isolates are able to infect CD4 T cells, mono- cytes and macrophages, and depend on the use of CCR5 and CD4 for viral entry. The interaction of gp120 and the cellular receptors is now understood in more detail. Binding to CD4 induces confor- mational changes in gp120 that promote a more efficient interaction of the V3 loop of gp120 with its respective co-receptor. Membrane fusion is dependent on gp120 co-receptor binding. Gp41, as the transmembrane part of the envelope glycoprotein gp160, is crucial for the fusion of the viral and host cell membrane. Similar to influenza hemagglutinin, it was postulated that consequent to the binding of gp120 28 The Basics M-tropic HIV isolate T-tropic HIV isolate Figure 4: Inhibition of viral entry of CCR5-utilizing (monocytotropic) and CXCR4-utilizing (T cell tropic) HIV isolates by the natural ligands of the chemokine co-receptors CCR5 and CXCR4 to CD4, a conformational change is induced in gp41 that allows gp41 to insert its hydrophobic NH2 terminal into the target cell membrane. Gp41 has been compared to a mouse trap and a crystallographic analysis of the ectodomain of gp41 seems to confirm that (Chan 1997). The identification of crucial amino acid sequences for this process was used to synthesize peptides that bind to gp41 within the domains, are critical for the induction of conformational changes, and may inhibit membrane fusion. T-20 is the first of several peptides that bind to gp41 that was tested in clinical trials to suppress viral replication (see chapter on ART). T-20 is available as a therapeutic option for patients with advanced HIV. One disadvantage of T-20 is that it must be taken subcutaneously twice daily. Despite a broad spectrum of potentially available co-receptors (e. The importance of CCR5 as the predominant co-recep- tor for M-tropic HIV isolates is underscored by another observation. The majority of individuals with a genetic defect of CCR5 are resistant to infection with HIV-1 (Liu 1996). In vitro experiments show that lymphocytes derived from these individuals are resistant to HIV-1 infection using M-tropic isolates but not to infection with T-tropic isolates. Lymphocytes from these individuals do not express CCR5 on their cell surface and genetically have a 32-basepair deletion of the CCR5 gene. Worldwide, a few patients have been identified that have acquired HIV-1 infection despite a homozygous deletion of the CCR5. As expected, all of them were infected with CXCR4-using HIV-1 isolates. In epidemiological studies, the allelic frequency of the CCR5 gene deletion is 10–20% among Caucasians, particularly amongst those of Northern European descent. The frequency of a homozygous individual is about 1% in Caucasians (Dean 1996). Studies conducted on African or Asian populations, however, do not find this 32-basepair deletion. Individuals that are heterozygous for the 32-bp deletion of the CCR5 show a decreased expression of CCR5 on the cell surface and are more frequently encoun- tered within cohorts of long-term non-progressors compared to patients who have a rapid progression of disease (Dean 1996). In addition, HIV-infected individuals who are heterozygous for the 32-bp deletion, have a slower progression to AIDS, a better Pathogenesis of HIV-1 Infection 29 treatment response to ART, and lymphoma incidence is decreased. These data demon- strate that the density of CCR5 on the cell surface is not only a limiting factor for replication of HIV in vitro but in vivo as well. Transmission of HIV-1 is caused by M-tropic viruses in most cases – even when T-tropic isolates predominate in the donor. In early HIV infection, mostly M-tropic virus isolates can be found. In patients who have a rapid progression of disease (rapid drop in CD4 T cell count), virus isolates that use CXCR4 as a predominant co-recep- tor tend to be frequently isolated from their cells in comparison to patients with a stable CD4 T cell count. The expression of co-receptors on CD4 lymphocytes depends on their activation level. CXCR4 is mainly expressed on naive T cells, whereas CCR5 is present on activated and effector/memory T cells. The blockade of CCR5 therefore seems to represent a promising target for therapeutic intervention (see chapter on ART).
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