By X. Grimboll. Medical College of Pennsylvania and Hahnemann University. 2018.
Most of these were endocrine problems that involved the testicles discount allopurinol 100 mg without prescription, ovaries order allopurinol 300mg with visa, or adrenal glands and all were congenital buy allopurinol 300 mg lowest price. When I ﬁnally got to the operating room after stopping to mask up 100 mg allopurinol, put on greens, paper boots, and a cap, I found the surgeon and the gynecologist sitting on stools and leaning against the wall. Tey pointed to the table, where the patient was still under general anesthesia. Tey wanted me to look in the abdomen and give them some explanation for what they had found. Apparently the surgeon had begun operating for acute appen- dicitis on what he thought was a young man. When he got into the abdominal cavity, he found not only acute appendicitis but all the 40 Te Woman Who Believed She Was a Man 41 internal organs of a normal female. Tere they were—ovaries, fallopian tubes, and a fully devel- oped uterus. I scrubbed and gowned up so I could palpate the or- gans and get more direct information. I could feel the uterine cer- vix at the end of the uterus and below it what I thought could be the upper vaginal vault. I asked them to undrape the patient so I could examine the ex- ternal genitalia. Despite all eﬀorts, I could not ﬁnd any masses that might represent testicles in the external areas of his skin. Te patient was prominent in the northern part of the state in business and politics. Tirty-ﬁve years old, he had married his high school sweetheart and they had adopted a boy and a girl. I asked them then to bi- opsy what I thought were ovaries and have the pathologist call me when he had the frozen sections ready. I needed to know if there was any hint of testicular tissue present, if these were just ovaries, or both. Te surgeons should then continue with a complete hys- terectomy and remove all internal genital tissue. I had a tragic experience with another adult patient, who committed suicide when some in- sensitive physician had told the person outright that he was actu- ally a she. It was not going to be easy to keep the facts quiet, but I thought it essential to protect the patient from the cruel and unneeded harm 42 Symptoms of Unknown Origin that would come if any of the ﬁndings leaked out. Te three of us took a vow to cover up all the ﬁndings once we ﬁgured out what was going on. An emerging literature also conﬁrmed the great harm and suicides that can be triggered by bluntly telling people reared in one sex that they are the opposite sex. Te literature of that time indicated that forced switches in gender after the age of two years were more often harmful than helpful. I am referring only to patients with ambiguous external or internal genitalia. We agreed we would label everything in ambiguous terms, such as gonads or internal genitalia structures. We agreed to stick closely to the fact that this was a man who had some disorder with his internal genitals and that they had just not developed perfectly. I told her everything was going along ﬁne with the appendectomy and that her husband was in very good condition. I then told her the surgeon had uncovered the gonads and some genital tissue in the operative ﬁeld. Tis was what I needed to discuss with her, I said, because we thought the best thing to do would be to remove these tissues because they were not functional and because they could serve only as potentials for cancer later on. I stuck as close to the facts as I could, using generic terms as much as possible, and guessing that she at least knew her husband did not have testicles that were descended. I asked her to tell me what she knew about his undescended tes- ticles, and here I used that term on purpose. He had developed sexually very early, she thought around age ﬁve or six.
Should therapy whom AML developed as a progression of a be successful discount allopurinol 300mg with visa, a complete remission is obtained prior bone marrow disorder either of a myelo- which is deﬁned as normal blood counts and bone proliferative nature or more commonly following marrow with no evidence of leukaemia buy generic allopurinol 300 mg line. Remission rates are approximately a subgroup representing about 10% of patients 75% in younger patients but are only 50% in with AML buy 300 mg allopurinol otc, predominantly in younger adults and children buy 100 mg allopurinol with mastercard. There have been major improvements in infec- balanced translocation between chromosomes 15 tious disease and transfusion supportive care so and 17, resulting in a mutation of the gene that, today, the major cause of initial treatment coding for the retinoic acid nuclear receptor. Randomised sensitivity to an oral retinoid, all-trans retinoic trials comparing different types of anthracyclines, acid (ATRA), which has appreciably fewer side different doses and schedules of administration effects than traditional chemotherapy. A series of ara-c, and the use of growth factors for sup- of randomised trials have elucidated the optimal portive care, have not improved these induction means of combining ATRA with chemotherapy results. With appropriate post-remission therapy, such that more than 70% of patients with approximately 35% of patients less than 50 years this previously devastating leukaemia can be of age remain disease-free after three years, with cured. It is hoped HAEMATOLOGIC CANCERS 143 that similar strategies with different compounds However, there are a number of both practical can be discovered for other AML variants with and biologic issues complicating the conduct of discrete activating mutations, as has recently also such trials: been achieved in patients with chronic myeloid leukaemia (CML) with the use of the tyrosine • Evaluation of post-remission manipulations kinase inhibitor imatinib mesylate (STI571), is made more difﬁcult by the low com- which speciﬁcally targets the abnormal enzyme plete response rate, so that less than 50% produced by the bcr/abl mutation characteristic of patients initially entered on trial are eli- of CML. In addi- Some studies have suggested differential res- tion, many such patients are not candidates ponsiveness of AML subtypes to different types for intensive therapy because of compromised of chemotherapy. In particular, patients with organ function from toxicities encountered dur- more favourable balanced translocations seem ing induction, and because many older patients to beneﬁt from high-dose ara-c-based consoli- do not recover fully normal blood counts even dation therapy. In contrast, patients with poor after a signiﬁcant anti-leukaemic response dur- prognosis chromosomal changes do not bene- ing induction. Stem cell as far from aggressive medical ministrations transplant is currently not a possibility for older as possible. Because of this, many treatment coop- erative groups have devised different therapeutic Thus, randomised studies of new therapies intro- approaches for older and younger patients, with duced post-remission need larger numbers of manipulations of stem cell transplantation being patients to account for this drop-off in patients evaluated in the latter group. This represents a major issue since only a small fraction of such patients are captured for clinical trials. IMPROVING THERAPY FOR OLDER Furthermore: PATIENTS WITH AML • AML in older individuals is extremely hetero- Rates of complete remission are much lower and geneous. Some therapies might be appropriate remission duration more abbreviated in patients only for certain AML subtypes and positive greater than the age of 60 years as a consequence effects can be missed when tested in the over- of more intrinsic drug resistance and more base- all AML population. This may be particularly line organ dysfunction than are encountered in true for newer targeted therapies. New therapeutic approaches • A focus on patients with highly resistant should focus both on increasing remission rates disease represents a particularly high hurdle as well as on prolonging remission and enhanc- for new therapies and treatments. Many AML nonetheless important, beneﬁts which could studies have focused on older patients because be of value to other patient groups could be of the large numbers of such patients available missed by studying only patients in very poor for studies as well as the feeling that the overall prognostic groups. In 144 TEXTBOOK OF CLINICAL TRIALS addition to a continued supply of cytotoxic on Phase II data alone which showed beneﬁt in drugs, there will be large numbers of anti- patients with resistant disease and otherwise few angiogenesis compounds, immune modulators, therapeutic options. Many of the non-cytotoxic therapeutic approaches also have the allure of oral treatment with potentially much less toxicity. Because of the nature of AML and its treat- If an agent can be safely added to the ment, several statistical issues in the design and usual dose of conventional therapy, it might analysis of clinical trials need special attention. Possible study designs for trials of new post-remission therapies are shown in Table 9. The post-remission phase observation without treatment which produces is sometimes further divided into earlier consol- very few if any long-term disease-free survivors idation therapy and later maintenance therapy, and shorter CR durations. The choice among but for our purposes here, two phases are suf- the various randomised approaches might be ﬁcient. It is natural to design studies to compare inﬂuenced by the unique features of the agent therapies in each of these two phases, leading to being tested. Also, given the very poor results factorial designs, in which patients are randomly observed with standard therapy, it could be assigned to one of two or more induction thera- argued that a straightforward Phase II trial in pies (the ﬁrst factor) and then to one of two or which the new agent is evaluated alone could more maintenance therapies (the second factor). However, a number of anti-cancer agents and well-known statistical design.
Sometime in her ﬁrst year of life buy 100 mg allopurinol amex, she had a protracted encounter with a physician who told her mother that Regina was sickly and underdeveloped proven allopurinol 300mg. Regina spent more than an hour recounting all her unhappy encounters with the medical profession generic 300mg allopurinol fast delivery. Rather than skirt over these order allopurinol 100mg with mastercard, I drew her out on each case, asking who the doctor was, what medicine had been prescribed, and what surgery was performed. I asked her to tell me in great detail all the side or toxic eﬀects of each drug and every complication she had with each operation. She was smiling and sometimes laughing as she told me of one bad outcome after another. She said she was allergic to or had be- come nauseated on every known pain medication. She knew them all by name and dosage and told me what each one did that was bad for her—skin rashes, headaches, nausea, constipation, burning lips, itching legs, water- ing eyes, ringing ears, and many more symptoms that the pills that were supposed to help her had caused. After the ﬁrst back operation, she could not walk for three months and then only with a cane. Tese complications were compounded by many of the drug reactions she had just listed. Between the ﬁrst and second back operations, she had a mis- 144 Symptoms of Unknown Origin carriage and had to have a D and C (dilation and curettage) to stop the bleeding she had discovered in the middle of the night; she said she was nearly bleeding to death before they got me to the hospi- tal. She was so weak after the second back operation that her husband had to carry her in his arms around the house and to the bathroom. Te third back operation had been a year before I saw her, and the numbness in both feet that followed that operation had just cleared up a few months ago. I would interrupt her to amplify details for each story and each com- plication or drug reaction. I left after the ﬁrst visit, saying that I had a lot of things to think about and that I did not know what I would recommend. About this time in my search for new ways to deal with diﬃcult patients like Regina, I had read a book called Change (Watzlawick, Weakland, and Fisch 1974) Te authors described a patient very much like Regina who they posited liked to defeat experts. Tey mentioned a class of people who, for whatever reason, play a game of defeating experts. Tere is only one way that an expert (a clini- cian, in this case) can be defeated and help the patient at the same time, the authors suggest: a therapeutic paradox. According to the method described in Change, the patient (in this case, Regina) is saying unconsciously: No matter what you do, I will stay sick. You have heard all my old experiences with doc- tors, and in each one I did not get well. In fact, no matter what the A Paradoxical Approach 145 doctor did, I got worse. Te therapeutic paradox the authors suggested is what I tried with Regina. I discussed the case with the orthopedist and he agreed with the approach I outlined. He had nothing to oﬀer the patient and could think of no other tests or operations that would help. She had been in physical therapy for months with no help; in fact, she thought she had strained her back even further with some of the treatments. I asked the head nurse on the unit to be there and witness what I told Regina. I was very anxious because I had never been as frank as I intended to be with Regina, and I could not predict what reaction she might have. I intended to tell her exactly what I thought about her present condition and what I thought would happen to her in the future. I was going to follow the rules of the paradox, because I believed it was as close to the truth as I could get. If it did not, I could not imagine how it would hurt her except to make her angry. I recounted in great and slow detail all her previous operations and the complications and problems she had after each one. After I went over all the operations, I went on to the drugs and retold the side eﬀects and toxic reactions she had told me about.
Because the same formalism applies to each level of the hierarchy generic 300mg allopurinol fast delivery, it provides a tool for the rigorous study of coupled biological systems in terms of elementary Mathematical Modeling of Neuromimetic Circuits 141 mechanisms order allopurinol 100mg free shipping. Neural Field Equations Based on S-Propagators Let us describe the neural network based on the hierarchical 3-D representation in ﬁgure 7 purchase allopurinol 100 mg overnight delivery. There are two di¤erent time scales corresponding to the two following functions: activity (milliseconds) and synaptic modulation (seconds) 100 mg allopurinol free shipping. For each of them, the structural hierarchy is given in terms of neurons (axon hillocks), synapses, and channels (ﬁgure 7. Functional interactions are for activity, the membrane po- tential c that propagates from one neuron at r0 to another at r and for synaptic mod- ulation, the postsynaptic potential F at s, or equivalently, synaptic e‰cacy m. Let the density of neurons at r be rðrÞ and the density connectivity between the neurons at r0 and the synapses at s0 be p 0 0. For synapses at s in neurons at r, the density connec- r s tivity prs is determined by the connectivity in the postsynaptic neuron between spines and soma where the membrane potential is measured. A similar hierarchical structure in the synapses in which the channels are distributed leads to a similar ﬁeld equation for the functional interaction at this level, say g, given the anatomy of the system. Operators are determined by the explicit analytical relationship between input and output: Pðr0Þ applies to c; that is, it transforms the action potential c into the postsynaptic potential f using the synaptic e‰cacy s in the activity time scale. The structure of the ﬁeld equation is such that these operators correspond to an input- output block model, that is, a nonlinear transfer function. PCðrÞ applied to post- synaptic potentials f, and then integrated over all the pathways gives rise to the membrane potential at r. The neural ﬁeld equations derived using the S-propagator formalism for the c-ﬁeld at ðr; tÞ in the time scale fTg, and with the unknown factor Kðs0; s; dÞ (in case of linearity for the propagators P) for the f-ﬁeld equation at ðs; tÞ in the time scale ftg, are given by Eq. Each of these equations corresponds to a level of functional organization. These two levels of functional organization are coupled by a relationship, for example: Et A ½ti; ti þ Dt: sðtÞ¼sðtiÞ¼mðtiÞ or hsðtÞiDtðtiÞ¼mðtiÞ; ð7:8Þ where Dt is the time unit deﬁned experimentally and hsðtÞi denotes the average value of sðtÞ taken over this time interval. Application of the Formalism The Cerebellum and the Coordination of Movement Clinical studies have established that the coordination of movement depends on speciﬁc circuits in the cerebellar cortex and on highly organized interactions among several nuclei in the brain (Thompson, 1986, 1990). Over the past few years, the adaptive control of movement has been extensively investigated through mathemati- cal studies of artiﬁcial as well as biological neural networks (Barto et al. Much e¤ort has gone into determining the mechanisms of pattern learn- ing and recall; in other words, toward deﬁning the conditions of stability in dynamic systems. Mathematical Modeling of Neuromimetic Circuits 143 The cerebellar cortex is a network of networks. An element of the cerebellar cor- tex, called the Purkinje unit, consists of ﬁve types of cell: the Purkinje cell, which has the largest number of dendrites; the granular cells; the Golgi cell; and the basket and stellar cells. The geometry of the cortex allows us to deﬁne (approximately) a Pur- kinje unit. Consider a granular cell (gc) belonging to the unit containing the nearest Purkinje cell it is in contact with. Then (gc) may be considered to belong to a speciﬁc unit labeled k if the following conditions are satisﬁed: (gc) synapses with at least one Purkinje cell of unit k, the distance between (gc) and the Purkinje cells is the smallest distance between (gc) and any Purkinje cell it is in contact with outside the unit, and (gc) synapses with at least one Golgi cell of unit k. The basket and stellar cells included in the unit are those that are in contact with the Purkinje cell of unit k. This unit may be divided into two subsystems, the granular cell subsystem (GCS), that is, the neural network composed of granular cells (ﬁgure 7. The Purkinje unit, which is the repeating unit of the cerebellar cortex, is thus the basic element of a hierarchical network. We know that the function of the cerebellar cortex is the learning and recall of spatiotemporal patterns (Thompson, 1994). Therefore, a satisfactory transformation of the cerebellum would Y F X1...
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