窗 The hospital window

《窗》 　　

在一家医院的病房里，曾住过两位病人，他们的病情都很严重。这间病房十分窄小，仅能容下他们俩人。病房设有一扇门和一个窗户，门通向走廊，透过窗户可以看到外面的世界。其中一位病人经允许，可以分别在每天上午和下午起身坐上一个小时。这位病人的病床靠近窗口。而另一位病人则不得不日夜躺在床上。当然，两位病人都需要静养治疗。使他们感到痛苦的是，两人的病情不允许他们做任何事情借以消遣，只有静静的躺着。而且只有他们两个人。两人经常谈天，一谈就是几个小时。他们谈起各自的家庭，各自的工作，各自在战争中做过什么，等等。 　　每天上午和下午，时间一到，靠近窗的病人就被扶起身来，开始一小时的仰坐。每当这时，他就开始为同伴描述起他所见到的窗外的一切。渐渐地，每天的这两个小时，几乎就成了他和同伴生活中的全部内容了。 　　很显然，这个窗户俯瞰着一座公园，公园里面有一泓湖水，湖面上照例漫游着一群群野鸭、天鹅。公园里的孩子们有的在扔面包喂这些水禽，有的在摆弄游艇模型。一对对年轻的情侣手挽着手在树阴下散步。公园里鲜花盛开，主要有玫瑰花，但四周还有五彩斑斓、争相斗艳的牡丹花和金盏草。在公园那端的一角，有一块网球场，有时那儿进行的比赛确实精彩，不时也有几场板球赛，虽然球艺够不上正式决赛的水平，但有的看总比没有强。那边还有一块用于玩滚木球的草坪。公园的尽头是一排商店，在这些商店的后边闹市区隐约可见。 　　躺着的病人津津有味地听这一切。这个时刻的每一分钟对他来说都是一种享受。 描述仍在继续：一个孩童怎样差一点跌如湖中，身着夏装的姑娘是多么美丽、动人。接着又是一场扣人心弦的网球赛。他听着这栩栩如生的描述，仿佛亲眼看到了窗外所发生的一切。 　　一天下午，当他听到靠窗的病人说到一名板球队员正慢悠悠地把球击得四处皆是时，不靠窗的病人突然产生了一个想法：为什么偏是他有幸能观赏到窗外的一切？为什么自己不应得到这种机会的？他为自己会有这种想法而感到惭愧，竭力不再这么想。可是，他愈加克制，这种想法却变得愈加强烈，直至几天以后，这个想法已经进一步变为紧挨着窗口的为什么不该是我呢？ 　　他白昼无时不为这一想法所困扰，晚上，又彻夜难眠。结果，病情一天天加重了，医生们对其病困不得而知。 　　一天晚上，他照例睁着双眼盯着天花板，这里，他的同伴突然醒来，开始大声咳嗽，呼吸急促，时断时续，液体已经充塞了他的肺腔，他两手摸索着，在找电铃的按钮，只要电铃一响，值班的护士就立即赶来。 　　但是，另一位病人却纹丝不动地看着。心想，他凭什么要占据窗口那张床位呢？ 　　痛苦的咳嗽声打破了黑夜的沉静。一声又一声···卡住了···停止了···直至最后呼吸声也停止了。 　　另一位病人仍然继续盯着天花板。 　　第二天早晨，医护人员送来了漱洗水，发现那个病人早已咽气了，他们静悄悄地将尸体抬了出去，丝毫没有大惊小怪。 　　稍过几天，似乎这时开口已经正当得体。剩下的这位病人就立刻提出是否能让他挪到窗口的那张床上去。医护人员把他抬了过去，将他舒舒服服地安顿在那张病床上。接着他们离开了病房，剩下他一个静静地躺在那儿。 　　医生刚一离开，这位病人就十分痛苦地挣扎着，用一支胳膊支起了身子，口中气喘吁吁。他探头朝窗口望去。 　　他看到的只是光秃秃的一堵墙。 　　 　　

The hospital window 　　

Two men, both seriously ill, occupied the same hospital room. One man was allowed to sit up in his bed for 　　an hour each afternoon to help drain the fluid from his lungs. His bed was next to the room's only window.The 　　other man had to spend all his time flat on his back. 　　The men talked for hours on end. They spoke of their wives and families, their homes, their jobs, their 　　involvement in the military service, where they had been on vacation. Every afternoon when the man in the bed 　　by the window could sit up, he would pass the time by describing to his roommate all the things he could see 　　outside the window. The man in the other bed began to live for those one hour periods where his world would be 　　broadened and enlivened by all the activity and color of the world outside. 　　The window overlooked a park with a lovely lake. Ducks and swans played on the water while children sailed 　　their model boats. Young lovers walked arm in arm amidst flowers of every color and a fine view of the city skyline 　　could be seen in the distance. As the man by the window described all this in exquisite detail, the man on the other 　　side of the room would close his eyes and imagine the picturesque scene. 　　One warm afternoon the man by the window described a parade passing by. Although the other man couldn't 　　hear the band - he could see it. In his mind's eye as the gentleman by the window portrayed it with descriptive words. 　　Unexpectedly, an alien thought entered his head: Why should he have all the pleasure of seeing everything while I 　　never get to see anything ? It didn't seem fair. As the thought fermented the man felt ashamed at first. But as the 　　days passed and he missed seeing more sights, his envy eroded into resentment and soon turned him sour. He 　　began to brood and he found himself unable to sleep. He should be by that window - that thought now controlled his life. 　　Late one night as he lay staring at the ceiling, the man by the window began to cough. He was choking on the 　　fluid in his lungs. The other man watched in the dimly lit room as the struggling man by the window groped for the 　　button to call for help. Listening from across the room he never moved, never pushed his own button which would 　　have brought the nurse running. In less than five minutes the coughing and choking stopped, along with the sound 　　of breathing. Now there was only silence ----- deathly silence. 　　The following morning the day nurse arrived to bring water for their baths. When she found the lifeless body of 　　the man by the window, she was saddened and called the hospital attendants to take it away -- no works, no fuss. 　　As soon as it seemed appropriate, the other man asked if he could be moved next to the window. The nurse was 　　happy to make the switch, and after making sure he was comfortable, she left him alone. 　　Slowly, painfully, he propped himself up on one elbow to take his first look. Finally, he would have the joy of 　　seeing it all himself. He strained to slowly turn to look out the window beside the bed. 　　It faced a blank wall.

Unravel the mysterious milk in gastric management

 Written by LAW JIA JUIN

There are many articles, forums and websites on the net debating on the usage of milk for gastric acid. Some said milk should be avoided during a gastric attack while some claimed that milk is a good reliever for gastric. No doubt ,milk is a good reliever for the pain caused by acute/ sudden gastric attack .

Firstly, it is an effective buffering agent for acid in stomach , secondly ,the protein in it feed as a food to prevent the digestion of stomach wall by oversecreted acid.

Despiting that milk is a good short term reliever to acute gastric attack , it is not used as a long term approaches for gastric treatment or prevention ,this is bcz milk is high in protein ,it can induce gastric secretion, for long term prevention of gastric attack water is a better choice than milk. Though eating garlic is also thought to be a good preventative measure, but most of the gastrointestinal specialist suggested that garlic can worsen the situation of patient with GI problem.

People with frequent gastric attack and reflux is advised to undergo specialized diagnosis for peptic ulcer and peptic cancer, in order to localize the area and site of treatment, since there are many different type of ulcer and caused ,involving those caused by bacterial eg H.pylori bacterial.

AUTHOR : H.PYLORI CAUSED OVERSECRETIN OF GASTRIC ACID AND ALSO CAUSED DAMAGES TO STOMACH WALL, LEADING TO ULCER OR PERFOLATION

Conclusion, drink a cup of milk or take other antacid  ONLY WHEN the pain is extreme during an acute attack, following WITH plenty of water. This is a symptomatic treatment. Diagnosis for underlying causes are critical, do not hesitate to see a doctor to sort out the culprit of gastric and ulcer pain, having a regular diet and living lifestyle is also important to increase the prognosis of treatment.


Antacid for pharmaological treatment of gastric



Pre-tablet Granulation by LAW JIA JUIN

Contents of this article:

1.      Introduction

2.      Results and calculation

3.      Discussion

4.      Conclusion

1.Introduction

In this part of my report, I am going to discuss on what is meant by granulation, the importance of granulation, as well as the methods used in granulation.

So what is meant by granulation? Granulation is defined as a process where by small particle gathered into large permanent masses in which the original particle can still be identified. Besides that granulation can also be defined as a process in which fine, well mixed powder particles are adhered together and form a larger, multiparticle entities. The granules produced should be non-friable and have a suitable mechanical strength, this is to prevent the segregation of powders during compression and tableting processes. Pharmaceutical granules have a size range between 0.2-4.0 mm depending upon the subsequent use of them.

Some people may wonder that why is granulation so important in drug manufacturing processes? The reasons are because granulation increases the average particle size of our drugs. This allow the storage of raw material to become easier (since there are less dusty now). Besides that, by increasing the average particles size, the flowability of our drugs and excipients can be increased during the process of manufacturing. Optimum flowability is required for the better filling of capsule and tableting. This is because with the good flowabilty, the mass variation of our final product can be reduced, and also the differences of mass between different batches of drugs produced can be minimized. In addition to that granulation also increases the quality of our drugs especially those made into tablet form, this is because granules of optimum size allow better compression during tableting, and also granules with uniform sizes have less chances of segregation after the process of tableting.

The process of granulation can be divided into 3, they are dry granulation, wet granulation and direct compression. In dry granulation, the primary powder is aggregated by applying high pressure onto it. There are two main processes to be chosen ,either a large slug is formed in a heavy duty tableting press (slugging) or a sheet of pressed materials are formed from the direct squeezing of materials between two rollers (roller compaction).  These slugs and materials’ sheets are considered as intermediate .These intermediate products are then broken down using a suitable milling method to produce granular material which is then sieved to separate the desired fraction range. The fine powder left may be reworked to avoid waste. There is no fluid involved in dry granulation.

Wet granulation involves the mixing of dry primary powder particles together with fluid which consisting of binder and a suitable solvent .The solvent of the binder must be volatile so that it can be removed easily upon drying. Typical liquids include water, ethanol and isopropanol either alone or in combination. Water is commonly used for economical and ecological reasons. However it has certain disadvantages such as it may adversely affect drug stability, causing hydrolysis of susceptible products besides that it also needs a longer drying times than organic solvents due to its’ high boiling point. In wet granulation the powders is well mixed before an appropriate amount of binder solution is been added. A small lump of wet powder is grabbed using hand and then this lump of wet powder is broken into two pieces to see whether it manage to break smoothly without any fragmentation, if this is achieved,  complete granulation and appropriate amount of binder solution is said to be added. All the wet powder mass is then make into a big round lump and then sieved into small wet granules using selected sieve. The wet granules are then dried using oven. The dried granules formed are then sieved the second time to separate out the fine from the dried granules.

Direct compression method is similar to dry granulation method it does not need any binder solution. The dry powders and its’ excipient are compressed directly using puncher. Compression caused the temperature of powders to be increased, the heat energy will melt some portion of the powders into molten state, the adjacent powders are then able to fuse together. When the punch is raised up after compression, heat energy from the powder is lost to the environment, and the fused molten powder will be able to recrystallize back into a larger granules of uniform size

2. Results and calculations

A) calculation of the amount of dry binder added per tablet

Density of binder solution= 2.8gm/ml

Percentage of binder solution= 6 %

Volume of binder solution added= 8ml

Weight of binder solution added= density x volume

                                      =2.8 x 8= 22.4gm

Amount of dry binder added= weight of binder solution added x ( % of binder solution/100)

                                               = 22.4 x 0.06

                                               =1.344gm

Amount of dry binder per tablet = total amount of dry binder/ (500 tablets)

                                                    =1.344/500= 2.688 x10^-3 gm = 2.688 mg dry powder per tablet

B) Calculation of the percentage of granules.

Percentage of granules= [weight of granule/ ( weight of granules + weight of fines)] x100%

                                    =[62.65/(62.65 +22.36)] x 100 = 73.7%

Percentage of fine= [weight of fine / ( weight of granules + weight of fines) ] x 100%

                              =100- 73.70=26.3%

**weight of granule: those collected above the sieve after the second sieving.

**weight of fine: those collected below the sieve after the second sieving.

C) Percentage of moisture content of our granules

100- 96.62 (get from moisture balance)= 3.38%

3. Discussion

In this session ,I will basically discuss on the mechanism of wet granulation formation and also the analysis of my results.

The mechanism of fine powdres granulation varies from equipment to equipment. However the proposed granulation mechanism can be divided into 3 stages, first is nucleation, second is transition, and the last stage is ball growth. There are four types of ball growth namely coalesence, breakage ,layering, and abrasion transfer.

During nucleation the particle adhere due to the formation of liquid bridges this is the initial step of granulation because the adhered particles serves as a base for further enlargement of granules.

Enlargement of nucleus takes place when individual particle adhere to the nucleus ;or two or more nuclei combine among themselves.  These enlargements of nuclei  to form  granules are known as transitions.

If agitation is continued, an un-usable, over-massed granules will be formed, these granules are too large for pharmaceutical purposes.  Thus the granulation should always be stopped  at an optimum point.

There are four possible mechanisms of ball growth, there are  coalescence ,breakage ,layering and abrasion. Coalescence is a process by which two or more granules join to form a larger granule. Breakage is said to be happened if granules break into fragments which adhere to other granules, forming a layer of material over the surviving granule. Layering is a process in which a second batch of powder mix is added to a bed of granules, the powder will adhere to the granules, forming a layer over the surface and increasing the granule size.  Abrasion is a process by which some portions of a granule are worn off from the surface and bind to other granules, increasing their size. This usually happens during agitation and transferring of the granules.

In our experiment we are actually using wet granulation method. Wet granulation involves the usage of granulation fluid .This granulation fluid is actually a binder solution, in our case we are using maize solution as a binder.  The granulation fluid contains a solvent that must be volatile, so that it can be removed by drying.

During wet granulation, binder solution is added to powder bed and is distributed as films around and between the particles. The liquid (water) is distributed between particles in three states namely, pendular, capillary and funicular state.

Addition of a binder solution caused the formation of liquid films around the particles , this effectively decreases the bond distances between adjacent particles. The bond strength between particles are increased. Pendular marks the initial stage of liquid addition where liquid bridges begin to form. At thios point granules have lowest mechanical strength. Further addition of liquid leads to coalescence of the bridges to give the funicular stage.  In the capillary stage the void spaces within the granule is replaced with the liquid. Force within the granule is a combination of interfacial forces as well as negative capillary pressure. At this point the amount of binder solution added is said to be optimum, excessive addition of liquid produces the droplet stage, in this stage there will be no intragranular forces, granulation failed to happen

Now I am going to discuss on the results we get from this experiment. The percentage of fine we got was around 26.3 %, which is relatively high. This tells us that the binding of powders are not strong enough and therefore the granules we got can be easily segregated. This may be due to the amount of binder solution we used was too little or it may be due to other factors like inappropriate type of binder used or the distribution of binder solution was not uniform, some powders may not receive any binder solution. These fine powders can actually be collected and recycled so that they can form granules. To reduce the amount of fine and to increase the percentage of granules, we should make sure that the binder solution we use is appropriate and suitable for our materials. It is also important for us to determine the optimum volume of binder solution to be used, since too little or too much of binder solution can lead to loose binding of our powders and the granules may not formed or if it formed it will be too fragile and segregate easily. Since in our case the volume of binder solution used was 8ml, we can actually increase the volume of binder used to 10ml in order to improve the process of granulation. The percentage of moisture content of our granules is 3.38% which is within the range of 3-4%, so we can actually say that our drying process of granules formed is pretty well.

4.Conclusion

1.      The amount of binder solution used in this experiment is 8ml ( 2.688mg per tablet)

2.      The percentage of granules formed is 73.7%

3.      The percentage of fine is 26.3%

4.      The moisture content of our granules is 3.38%

5.      The Amount of binder solution used can be increased to 10 ml in order to increase the percentage of granules formed. Besides that the mixture of binder solution with powders must be improved, so that the binder solution can get into all the void spaces of our powders for better granulation. If these still don’t work then we can consider choosing a better binder.

NMR spectroscopy- useful link

http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/Spectrpy/nmr/nmr1.htm